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1
McCarthy, Andrew. "Eucalypt Ecology: Individuals to Ecosystems." Pacific Conservation Biology 4, no. 2 (1998): 174. http://dx.doi.org/10.1071/pc980174.
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Eucalypt ecologists in Australia finally have a text that is a comprehensive review of the current state of knowledge on eucalypt ecology. This book incorporates and expands on ideas found in Eucalyptus, the Universal Australian by Pryor and Johnson (1981) and Pryor's (1976) The Biology of Eucalypts.
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Bayly, Michael J. "Phylogenetic studies of eucalypts: fossils, morphology and genomes." Proceedings of the Royal Society of Victoria 128, no. 1 (2016): 12. http://dx.doi.org/10.1071/rs16002.
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The eucalypt group includes seven genera: Eucalyptus, Corymbia, Angophora, Eucalyptopsis, Stockwellia, Allosyncarpia and Arillastrum. Knowledge of eucalypt phylogeny underpins classification of the group, and facilitates understanding of their ecology, conservation and economic use, as well as providing insight into the history of Australia’s flora. Studies of fossils and phylogenetic analyses of morphological and molecular data have made substantial contributions to understanding of eucalypt relationships and biogeography, but relationships among some genera are still uncertain, and there is controversy about generic circumscription of the bloodwood eucalypts (genus Corymbia). Relationships at lower taxonomic levels, e.g. among sections and series of Eucalyptus, are also not well resolved. Recent advances in DNA sequencing methods offer the ability to obtain large genomic datasets that will enable improved understanding of eucalypt evolution.
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Espinosa-García, Francisco J. "Revisión sobre la alelopatía de Eucalyptus L'Herit." Botanical Sciences, no. 58 (April 27, 2017): 55. http://dx.doi.org/10.17129/botsci.1487.
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Some eucalyptus species can be associated to the production of zones where vegetation is absent, sparse and/or less diverse and vigorous than surrounding zones away from eucalypts. These zones have been documented with eucalypts growing as native or introduced species. Yield reduction and poor plant performance is frequent when some crops, annual or perennial, are planted within or around eucalypt stands. Although competition for water, light and nutrients can explain some of these inhibition patterns, it is insufficient to explain others. Field evidence suggests that allelopathy explains, at least partially, the aforementioned inhibition areas. Inhibition zones are absent where the soil does not accumulate allelochemicals and the watering or rainy regime leaches them out, or the plants surronding eucalypts are unaffected by the chemicals. Phenolic acids, tannins, flavonoids and/or terpenoids have been isolated from eucalypt bark, litter and leaves; leaf hates or extracts from these parts have been shown to be phytotoxic in vitro and in greenhouse experiments for most target speciestested. Allelochemicals are normally released, from intact, dead or alive, eucalypt tissues and accumulated in water or soil in concentrations high enough to produce allelopathic effects. Milled or chopped eucalypt parts release more allelochemicals and faster than intact parts. Although no published work contains a li the undisputed evidence required to demonstrate eucalypts allelopathy, the body of evidence in the published works suggests that some eucalypt species do produce allelopathic effects in natural conditions.
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Larcombe, Matthew J., Brad M. Potts, Rebecca C. Jones, Dorothy A. Steane, João Costa E. Silva, and René E. Vaillancourt. "Managing Australia’s eucalypt gene pools: assessing the risk of exotic gene flow." Proceedings of the Royal Society of Victoria 128, no. 1 (2016): 25. http://dx.doi.org/10.1071/rs16003.
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Most eucalypts are endemic to Australia but they have been introduced into more than 100 countries and there are now over 20 million hectares of eucalypt plantations globally. These plantations are grown mainly for pulpwood but there is expanding interest in their use as a renewable source of solid wood products and energy. In Australia, the eucalypt plantation estate is nearing one million hectares, located mainly in temperate regions and dominated by Eucalyptus globulus and E. nitens (subgenus Symphyomyrtus), which are grown mainly outside their natural ranges. While eucalypt species from different major subgenera do not hybridise, hybrids within subgenera are often reported, including hybrids with plantation species. Concerns were raised in the late 1990s that pollen-mediated gene flow from locally exotic plantation eucalypts may affect the integrity of adjacent native eucalypt gene pools. As Australia is the centre-of-origin of most eucalypt species used in plantations around the world, exotic gene flow is one of the many issues that require management for industry sustainability and certification purposes. We here summarise over a decade of research aimed at providing the framework and biological data to help assess and manage the risk of gene flow from these plantations into native gene pools in Australia.
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W. HART, PETER, and RICARDO B. SANTOS. "Changing the face of short fiber –a review of the eucalyptus revolution." June 2015 14, no. 6 (July 1, 2015): 353–59. http://dx.doi.org/10.32964/tj14.6.353.
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Eucalyptus plantations have been used as a source of short fiber for papermaking for more than 40 years. The development in genetic improvement and clonal programs has produced improved density plantations that have resulted in fast growing, increased fiber volume eucalypts becoming the most widely used source of short fibers in the world. High productivity and short rotation times, along with the uniformity and improved wood quality of clonal plantations have attracted private industry investment in eucalypt plantations. Currently, only a handful of species or hybrids are used in plantation efforts. Many more species are being evaluated to either enhance fiber properties or expand the range of eucalypt plantations. Eucalyptus plantations are frequently planted on nonforested land and may be used, in part, as a means of conserving native forests while allowing the production of high quality fiber for economic uses. Finally, eucalypt plantations can provide significant carbon sinks, which may be used to help offset the carbon released from burning fossil fuels. The development and expansion of eucalypt plantations represents a substantial revolution in pulp and paper manufacturing.
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Morais, Wagner Calixto de Castro, Norivaldo dos Anjos, and Terezinha Maria Castro Della Lucia. "Consumo Foliar de Eucalyptus spp. por Acromyrmex disciger (Mayr, 1887) (Hymenoptera: Formicidae)." EntomoBrasilis 4, no. 2 (July 22, 2011): 73–74. http://dx.doi.org/10.12741/ebrasilis.v4i2.89.
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O potencial produtivo de plantios florestais é reduzido, dentre outros fatores, pela ocorrência de pragas. No Brasil, as formigas-cortadeiras são os principais insetos daninhos à cultura do eucalipto. Dentre as espécies dessas formigas, Acromyrmex disciger (Mayr) se destaca na região Sudeste do Brasil. Entretanto, poucas são as informações a respeito de seu potencial de dano às plantações de eucalipto. Este trabalho teve por objetivo quantificar o consumo foliar de eucalipto por A. disciger, em condições de laboratório. Para isto, folhas frescas de Eucalyptus grandis W. Hill ex Maiden, Eucalyptus urophylla ST Blake e do híbrido E. urophylla x E. grandis foram oferecidas, com chance de escolha, à duas colônias de A. disciger, durante 24 horas, num total de oito repetições. O consumo foliar foi determinado pela diferença entre as massas de folhas e de suas sobras, após serem disponibilizadas às formigas. As operárias das duas colônias consumiram, respectivamente, 38,8 ± 3,2 g e 22,0 ± 2,3 g de folhas de eucalipto, por dia. Estes elevados valores podem sugerir estado de alerta para os danos que A. disciger pode causar nos plantios de eucalipto, merecendo, esta formiga-cortadeira, maior atenção.
Eucalypt leaf-consumption by Acromyrmex disciger (Mayr) (Hymenoptera: Formicidae)
Abstract. The productive potential of forest stands is reduced by pest occurrence among other factors. In Brazil, leaf-cutting ants are the most severe eucalypt pests. Acromyrmex disciger (Mayr) is prevalent in the south east Brazil. However, scarce information about its potential damage for Eucalyptus forests is available. This work deals to quantifying the eucalypt leaf-consumption by such specie of leaf-cutting ant. Fresh leaves were taken from trees of Eucalyptus grandis W. Hill ex Maiden, Eucalyptus urophylla ST Blake, and hybrid E. urophylla x E. grandis and served to different colonies of A. disciger, during 24 hours period, over eight different times. Leaf-consumption was calculated throughout fresh weights of leaves, before and after ants foraging. Each colony of A. disciger consumed 38.8 ± 3.2 g e 22.0 ± 2.3 g of eucalypt leaves, per day.
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Cabral, João Paulo. "A entrada na Europa e a expansão inicial do eucalipto em Portugal Continental." História da Ciência e Ensino: construindo interfaces 20 (December 29, 2019): 8–27. http://dx.doi.org/10.23925/2178-2911.2019v20espp18-27.
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Resumo As primeiras observações e recolhas de eucaliptos ocorreram nas grandes viagens inglesas e francesas ao Pacífico, em particular à Austrália, em finais do século XVIII. O género Eucalyptus L'Hér. foi estabelecido em 1788, e logo nas duas décadas seguintes seriam descritas, por botânicos franceses e ingleses, muitas espécies novas. O primeiro eucalipto cultivado em Inglaterra foi trazido, em 1774, na segunda viagem de James Cook. Em França, a introdução terá sido feita em 1804, no Jardim Botânico de Montpellier, na Alemanha em 1809, no Jardim Botânico de Berlim, e em Itália, em 1813, no Jardim Botânico de Nápoles. Em Portugal, a introdução do eucalipto foi muito posterior a estas datas. Na propriedade do duque de Palmela no Lumiar, foram plantados dois eucaliptos em 1850-1852. No Horto Botânico da Escola Médico-Cirúrgica de Lisboa, existia em 1852, pelo menos um espécimen, certamente para uso ou demonstração das suas propriedades terapêuticas. A partir da década de 1860, a expansão foi muito rápida. Em 1869, a companhia real dos caminhos-de-ferro portugueses iniciou a plantação de eucaliptos nas estações, casas de guarda e ao longo da via-férrea. As primeiras plantações em larga escala terão ocorrido na década de 1880 em propriedades perto de Abrantes arrendadas por William T. Tait. Em 1886 estavam já plantados 150 mil eucaliptos. Nesta mesma década começou a plantação, em escala apreciável, de eucaliptos nas Matas Nacionais. Em finais do século XX, tinham sido introduzidas em Portugal cerca de 250 espécies, sendo o Eucalyptus globulus Labill., a espécie largamente dominante. É interessante constatar que tendo sido um dos países europeus que mais tarde introduziu a cultura do eucalipto, Portugal é hoje, a nível mundial, um dos que apresenta maior percentagem da sua área florestal dedicada a esta cultura.Palavras-chave: eucalipto; jardins botânicos; Portugal. Abstract The earliest observations and collections of eucalypts occurred on the great English and French voyages to the Pacific, particularly Australia, in the late 18th century. The genus Eucalyptus L'Hér. was described in 1788, and soon in the following two decades, many species would be described by French and English botanists. The first eucalypt grown in England was brought in 1774 on James Cook's second voyage. In France, the introduction seems to have occurred in 1804, at the Botanical Garden of Montpellier, in Germany in 1809, at the Botanical Garden of Berlin, and in Italy, in 1813, at the Botanical Garden of Naples. In Portugal, the introduction of eucalypts was much later than these dates. In the property of the Duke of Palmela in Lumiar, two eucalypts were planted in 1850-1852. The Botanical Garden of the Medical-Surgical School of Lisbon had in 1852, at least one specimen, certainly for use or demonstration of its therapeutic properties. From the 1860s the expansion was very rapid. In 1869, the royal company of the Portuguese railways began planting eucalypts in the stations, guard houses and along the railroad. The first large-scale plantations occurred in the 1880s in properties near Abrantes leased by William T. Tait. By 1886, 150,000 eucalypts were already planted. In the same decade began the planting, on an appreciable scale, of eucalypts in “Matas Nacionais”. By the end of the 20th century about 250 species had been introduced in Portugal, being Eucalyptus globulus Labill., the species largely dominant. It is interesting to note that Portugal, one of the European countries that later introduced the eucalypt, is today, worldwide, one of the countries with the highest percentage of its forest area dedicated to this culture. Keywords: eucalypt; botanical gardens; Portugal.
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Majer, Jonathan D., and Harry F. Recher. "Are eucalypts Brazil's friend or foe? An entomological viewpoint." Anais da Sociedade Entomológica do Brasil 28, no. 2 (June 1999): 185–200. http://dx.doi.org/10.1590/s0301-80591999000200001.
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Vast areas of Brazil are being planted to Eucalyptus in order to provide renewable sources of timber, charcoal and cellulose. Although the rapid growth and productivity of various Eucalyptus species undoubtedly relaxes the pressure on logging of native forests, there are ecological costs. Firstly, some eucalypt species are vulnerable to pest outbreaks. A large number of native Lepidoptera, Coleoptera and leaf-cutting ants (Atta spp.), some of which have become pests, have been found on eucalypts growing in Brazil. Probably, the diverse myrtaceous flora of South America supports a fauna that can adapt to the introduced Eucalyptus species. Secondly, the leaf litter produced under Eucalyptus plantations differs substantially from that of native forests both in terms of its physical structure and chemistry, posing a range of problems for the native decomposer fauna. If microarthropod diversity is reduced, nutrient cycling could be impeded under eucalypt plantations. Thirdly, native forest canopies support a massive diversity and biomass of arthropods on which many birds, reptiles and mammals depend for food. The evidence is that invertebrate biomass and diversity are greatly reduced in the canopies of exotic eucalypt plantations. This, in turn, reduces the food-base on which forest arthropods and other animals depend, and hence their conservation status. This paper reviews the evidence for adverse ecological effects in Brazilian eucalypt plantations and suggests ways in which Brazil might meet its forestry needs, while conserving forest invertebrates and the vertebrates that depend on them.
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Macphail, Mike, and Andrew H. Thornhill. "How old are the eucalypts? A review of the microfossil and phylogenetic evidence." Australian Journal of Botany 64, no. 8 (2016): 579. http://dx.doi.org/10.1071/bt16124.
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Molecular age estimates for the Eucalypteae (family Myrtaceae) suggest that the eucalypts, possibly associated with fire, have been present for ~65 million years. In contrast, macrofossils and fossil pollen attributable to three important eucalypt genera (Angophora, Corymbia and Eucalyptus) in the Eucalypteae date to ~51–53 million years ago (mid-Early Eocene) in Patagonia, eastern Antarctica and south-eastern Australia. At present, there is no fossil evidence to show that eucalypts had evolved before this epoch, i.e. when Australia was part of eastern Gondwana, although this seems probable on the basis of molecular-dated phylogenetic analyses. The primary reason is the absence of macrofossils, whereas the earliest fossil eucalypt-type pollen recorded (Myrtaceidites tenuis) is attributed to Angophora and Corymbia, not Eucalyptus. This pollen type is recorded in Australia and Antarctica but not in New Zealand or South America. The only Myrtaceidites morphospecies found in Upper Cretaceous and Paleocene deposits in Australia is M. parvus, whose affinity lies with multiple extant Myrtaceae groups other than the Eucalypteae. In the present paper, we review current phylogenetic and microfossil databases for the eucalypts and assess this evidence to develop a ‘consensus’ position on the origin and evolution of the eucalypts in the Australian region.
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Ladiges, PY, F. Udovicic, and AN Drinnan. "Eucalypt phylogeny — molecules and morphology." Australian Systematic Botany 8, no. 4 (1995): 483. http://dx.doi.org/10.1071/sb9950483.
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Molecular (5S rDNA spacer and chloroplast DNA RnPs) and morphological data sets are informative at different levels of the eucalypt clade. They allow separate analysis of major subclades, the results of which, when combined, give a single, phylogenetic tree for Angophora Cav. and Eucalyptus L'Hér. For taxonomic revision, the tree supports the recognition of bloodwood eucalypts as monophyletic, but shows that informal subgenus Corymbia Pryor & Johnson is paraphyletic. The tree supports recognition of three major clades within the non-bloodwood eucalypts ('eudesmids', 'symphyomyrts' and 'monocalypts') and suggests relationships for taxa within each of these. Ovule and seed characters proved to be most informative in the morphological data set. The phylogenetic hypothesis suggests interpretations for homoplasious morphological characters, including parallel evolution of sepaline and petaline opercula (and associated stemonophore) and types of conflorescence.
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SIMÃO, EDUARDO DE PAULA, MIGUEL MARQUES GONTIJO NETO, SILVIO NOLASCO OLIVEIRA NETO, JOÃO CARLOS CARDOSO GALVÃO, EMERSON BORGHI, DENIZE CARVALHO MARTINS, and ÁLVARO VILELA RESENDE. "PRODUÇÃO DE GRÃOS E FORRAGEM EM FUNÇÃO DA DISPONIBILIDADE LUMINOSA EM SISTEMA DE INTEGRAÇÃO LAVOURA-PECUÁRIA-FLORESTA." Revista Brasileira de Milho e Sorgo 17, no. 1 (March 31, 2018): 111. http://dx.doi.org/10.18512/1980-6477/rbms.v17n1p111-121.
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RESUMO - Neste trabalho, objetivou-se avaliar a produtividade da forragem e grãos de milho e do capim braquiária em consórcio, submetidos a diferentes níveis de sombreamentos proporcionados pelos renques de eucaliptos, em sistema de Integração Lavoura-Pecuária-Floresta, na região de Sete Lagoas-MG. O experimento foi conduzido na área experimental da Embrapa Milho e Sorgo, em Sete Lagoas-MG, em área de cultivo de eucalipto (Eucalyptus urophylla, clone AEC 1528) implantado em 29 de outubro de 2013, em espaçamento 15x2 m entre plantas. Em 24 de novembro de 2015, foi realizada a semeadura simultânea em sistema plantio direto do milho (AG 8088 VT PRO) consorciado com capim braquiária (Urochloa brizantha cv. Marandu) em espaçamentos de 0,70 m entre linhas, a uma distância de 1 metro entre a primeira linha de semeadura do milho/braquiária e os renques de eucalipto. As produtividades de grãos e forragem de milho e de milho mais capim entre os renques de eucalipto foram semelhantes às produtividades em pleno sol a partir de 3,8 m de distância entre as linhas de milho e os renques de eucalipto. A produtividade de grãos e de forragens foi diretamente influenciada pela redução da distância entre as linhas de semeadura e os renques de eucalipto com três anos de implantação em espaçamento de 15x2. O componente arbóreo no sistema de Integração Lavoura-Pecuária- Floresta altera o ambiente no sub-bosque, reduzindo a incidência de radiação fotossinteticamente ativa entre os renques, diminuindo diretamente as produtividades de forragem e grãos de milho em cultivo consorciado com U. brizantha.Palavras-chave: Zea mays, U. brizantha, eucalipto, cultivo consorciado.GRAIN AND FORAGE PRODUCTION IN THE FUNCTION OF LUMINOUS AVAILABILITY IN INTEGRATED CROP-LIVESTOCK-FORESTRY SYSTEMSABSTRACT - The objective of this work was to evaluate the productivity of grass and maize forage, and maize grains submitted to different levels of shade provided by the eucalypt trees, in Integrated Crop-Livestock-Forest system, in the region of Sete Lagoas, State of Minas Gerais, Brazil. The experiment was carried out in the experimental area of Embrapa Milho e Sorgo, in Sete Lagoas, MG, in an area of eucalypt (Eucalyptus urophylla, clone AEC 1528) implanted on October 29, 2013, spaced 15x2 m between plants. On November 24, 2015, no-tillage system (AG 8088 VT PRO) was intercropped with Brachiaria grass (Urochloa brizantha cv. Marandu) at 0.70 m between rows, at distance of 1 meter between the first sowing line of maize/Brachiaria and eucalypt rows. The yields of maize forage, maize grains and Brachiaria among the eucalypt rows were similar to the productivities in full sun from 3.8 m distance between maize and eucalypt lines. Grain yield and maize fodder yields were directly influenced by the reduction of the distance between the sowing lines and the eucalypt rows with three years of implantation at 15x2 spacing. The arboreal component in Integrated Crop-Livestock-Forest system alters the environment in the sub-forest, reducing the incidence of photosynthetically active radiation among the ranks, directly reducing forage and maize grains yields in intercropping system with U. brizantha.Keywords: Zea mays, U. brizantha, eucalypt, intercropping system.
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Prior, Lynda D., Grant J. Williamson, and David M. J. S. Bowman. "Impact of high-severity fire in a Tasmanian dry eucalypt forest." Australian Journal of Botany 64, no. 3 (2016): 193. http://dx.doi.org/10.1071/bt15259.
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Dry eucalypt forests are believed to be highly fire tolerant, but their response to fire is not well quantified. We measured the effect of high-severity fires in dry eucalypt forest in the Tasmanian Midlands, the driest region on the island. We compared stand structures and fuel loads in long-unburnt (>15 years since fire) and recently burnt (<5 years since fire) sites that had been completely defoliated. Even in unburnt plots, 37% of eucalypt stems and 56% of acacia stems ≥5 cm in diameter were dead, possibly because of antecedent drought. The density of live eucalypt stems was 37% lower overall in burnt than in unburnt plots, compared with 78% lower for acacias. Whole-plant mortality caused by fire was estimated at 25% for eucalypt trees and 33% for acacias. Fire stimulated establishment of both eucalypt and acacia seedlings, although some seedlings and saplings were present in long-unburnt plots. The present study confirmed that eucalypts in dry forests are more tolerant of fire than the obligate seeder eucalypts in wet forests. However, there were few live mature stems remaining in some burnt plots, suggesting that dry eucalypt forests could be vulnerable to increasingly frequent, severe fires.
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Sbravatti Junior, José Antonio, Celso Garcia Auer, Ida Chapaval Pimentel, Álvaro Figueredo dos Santos, and Bruno Schultz. "SELEÇÃO IN VITRO DE FUNGOS ENDOFÍTICOS PARA O CONTROLE BIOLÓGICO DE Botrytis cinerea EM Eucalyptus benthamii." FLORESTA 43, no. 1 (April 24, 2013): 145. http://dx.doi.org/10.5380/rf.v43i1.26265.
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O Eucalyptus benthamii é uma das principais espécies de eucalipto plantadas na região Sul do Brasil, por sua resistência a geadas e por seu uso na produção florestal de madeira para fins energéticos. Na produção de mudas, uma das principais doenças ocorrentes em viveiros é o mofo-cinzento, causado pelo fungo Botrytis cinerea. Uma das alternativas para o controle dessa doença é o controle biológico com fungos endofíticos, os quais podem competir com os patógenos foliares de mudas de eucalipto. O objetivo deste trabalho foi isolar os fungos endofíticos provenientes de mudas de E. benthamii, identificá-los e selecioná-los para o controle de B. cinerea. Eles foram isolados do interior de tecidos vegetais desinfectados, identificados de acordo com critérios macro e micromorfológicos e classificados a partir de testes de controle biológico in vitro. Os resultados evidenciaram o potencial antagonista dos fungos Aspergillus sp., Penicillium sp. e Trichoderma sp. Nenhum desses fungos causou lesões em mudas de E. benthamii.Palavras-chave: Mofo-cinzento; eucalipto; viveiro.AbstractIn vitro selection of endophytes for biological control of Botrytis cinerea in Eucalyptus benthamii. Eucalyptus benthamii is one of the main eucalypt species planted in Southern Brazil, due to its resistance to frost and its use in the production of forest wood for energy purposes. During the production of seedlings, the main disease occurring in forest nurseries is gray-mold caused by the fungus Botrytis cinerea. One alternative for control this disease is biological control with fungal endophytes, which can compete with the foliar pathogens of eucalypt seedlings. The objective of this study was to isolate endophytic fungi from seedlings of Eucalyptus benthamii, identify and select them for B. cinerea control. These were isolated from the interior of disinfected plant tissues, identified according to macro and micromorphological criteria, and based on tests of biological control in vitro. The results revealed the potential antagonist of Aspergillus sp., Penicillium sp. and Trichoderma sp. No fungi caused lesions in E. benthamii seedlings.Keywords: Gray-mold; eucalypt; nursery.
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Bauhus, Jürgen, Aaron P. van Winden, and Adrienne B. Nicotra. "Aboveground interactions and productivity in mixed-species plantations of Acacia mearnsii and Eucalyptus globulus." Canadian Journal of Forest Research 34, no. 3 (March 1, 2004): 686–94. http://dx.doi.org/10.1139/x03-243.
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This study compared productivity in mixed-species plantations of Eucalyptus globulus ssp. pseudoglobulus (Naudin ex Maiden) Kirkpatr. and Acacia mearnsii de Wild with pure stands of each species and investigated how this might be explained by canopy stratification between species and changes in leaf characteristics of eucalypts. Investigations were carried out at a trial using the replacement series design, which consisted of the following combinations: 100% eucalypts (100%E), 75% eucalypts + 25% acacia (75%E:25%A), 50% eucalypts + 50% acacia (50%E:50%A), 25% eucalypts + 75% acacia (25%E:75%A), and 100% acacia (100%A). At 9.5 years, stem volume and biomass were highest in 50%E:50%A treatments. Canopy stratification occurred in all mixtures, with acacias in the lower and eucalypts in the upper canopy stratum. This and the increasing canopy light interception with increasing proportion of acacia in the mixture indicated that A. mearnsii is substantially more shade tolerant than E. globulus. Midcanopy foliage of E. globulus in the 50%E:50%A mixture had higher foliage nitrogen (N) but lower phosphorus (P) concentrations and lower light-saturated net photosynthesis rates (Amax) than those in the 100%E treatment. In addition, similar relationships between eucalypt crown volume and stem biomass across treatments indicated that eucalypt crowns were not more efficient in mixture. Our study indicates that the productivity gains in these mixtures may be partially attributable to aboveground niche separation between species.
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Wu, Yi Qiang, Hayashi Kazuo, and Ying Chun Cai. "Collapse-Type Shrinkage in Plantation-Grown Eucalyptus Cells When Subjected to Heat-Steam Treatment." Materials Science Forum 620-622 (April 2009): 217–20. http://dx.doi.org/10.4028/www.scientific.net/msf.620-622.217.
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Collapse-type shrinkage in plantation-grown Eucalyptus cells is a bottleneck to severely restrict its high-effective utilization as environment-friendly solid-wood products. So, measurement of collapse-shrinkage parameters on seven species of Eucalypts (Eucalyptus urophylla, E.grandis, E.urophylla×grandis, E.grandis ×urophylla, E. dunnii, E. cloeziana and E. pellita) have been carried out under three kinds of treated patterns (heating, steaming and combined treatment) by means of image analysis technique. The results indicated that the total shrinkage and residual collapse increase obviously with heating temperature and steaming time for five species of low-density eucalypts(E.urophylla, E.grandis, E.urophylla×grandis, E.grandis ×urophylla and E. dunnii), while increase slightly for other two species of higher-density Eucalypts (E.cloeziana and E.pellita). Combined treatment has not made the total shrinkage and residual collapse take on the additive trend, especially for higher-density Eucalyptus. Therefore, the results will provide the important practical significance for the reasonable processing of plantation-grown eucalypt wood.
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Dodson, JR, and CA Myers. "Vegetation and Modern Pollen Rain From the Barrington Tops and Upper Hunter River Regions of New South Wales." Australian Journal of Botany 34, no. 3 (1986): 293. http://dx.doi.org/10.1071/bt9860293.
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Vegetation was mapped using existing maps, Landsat interpretation, aerial photograph interpretation and some verification by ground surveys. Twenty-five moss cushions were collected to identify pollen rain and pollen indicators of vegetation for use in fossil pollen interpretation. Eucalyptus (10%), Poaceae (4-10%), Casuarina (4-5%), Asteraceae (Tubuliflorae) (0-4%) and Cyperaceae (0-2%) were the general components in the pollen rain of the region. Subtropical rain forest was characterized by Backhousia and low values of a wide range of taxa. Cool temperate rain forest had Nothofagus values above 40% and Eucalyptus values below 20%. Subalpine grasslands had Poaceae values above 45%, Eucalyptus values below 15% and small quantities of Epacridaceae and Goodeniaceae pollen. Subalpine forest and wet eucalypt forest formations had very similar pollen representation and could be confused in pollen spectra. However, Monotoca, Banksia, Leptospermum pollen and fern spores were more common in the wet eucalypt forests. Dry eucalypt formations were characterized by 2-20% values of Bursaria, Callitris and Dodonaea as well as eucalypt values.
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Barrett, DJ, TJ Hatton, JE Ash, and MC Ball. "Transpiration by Trees From Contrasting Forest Types." Australian Journal of Botany 44, no. 3 (1996): 249. http://dx.doi.org/10.1071/bt9960249.
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Temperate rainforests and eucalypt forests of coastal south-eastern Australia are distributed differentially with aspect. Rainforests, in which Ceratopetalum apetalum D.Don and Doryphora sassafras Endl. are the dominant tree species, occur on slopes of southerly aspect and along gully bottoms, whereas eucalypt forests, dominated by Eucalyptus maculata Hook., occur on upper slopes of northerly aspect and on ridge tops. Whether transpiration rates of trees differed across the rainforest-eucalypt forest boundary on north and south facing aspects was tested by measuring stem sap flow in trees in a single catchment during winter, summer and autumn. Differences in transpiration rate by trees in these stands were due to various combinations of biological and physical factors. Firstly, mean maximum transpiration rate per tree (crown area basis) was greater in rainforest on the gully bottom where deep soil water from down-slope drainage was greater than in eucalypt forest located upslope on the northern aspect. By contrast, there was no difference between maximum transpiration rates in rainforest and eucalypt forest on the southern aspect. Variation in transpiration rate between seasons was not related to variation in surface soil moisture content (< 0.35 m depth). Secondly, transpiration rates per unit crown area in rainforest at the gully bottom were associated with higher leaf area indices than upslope on the northern aspect. However, in rainforest upslope on the southern aspect, higher transpiration rates were not associated with higher leaf area indices. Thirdly, trees in eucalypt forest maintained similar sapwood moisture contents in summer as in winter and autumn, whereas sapwood moisture contents declined in rainforest trees in summer, suggesting that eucalypts had access to water from deep within the soil profile which was unavailable to more shallow rooting rainforest trees. Fourthly, higher modal and maximal sap velocities in eucalypt trees were partly due to wider xylem vessels and resulted in faster maximum sap flow and greater daily total water use in all seasons on both aspects than in rainforest species. Finally, as atmospheric demand for water increased from winter to summer, transpiration rates were mediated by stomata1 closure as indicated by lower average midday shoot conductance to water vapour during summer than other seasons. The interaction between microenvironment, which deteimines water availability, and physiological attsibutes, which determine tree water acquisition and use, may contribute to the differential distribution of rainforest and eucalypt forest with aspect in south-eastern Australia.
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Callaghan, John, Clive McAlpine, David Mitchell, Jane Thompson, Michiala Bowen, Jonathan Rhodes, Carol de Jong, Renee Domalewski, and Alison Scott. "Ranking and mapping koala habitat quality for conservation planning on the basis of indirect evidence of tree-species use: a case study of Noosa Shire, south-eastern Queensland." Wildlife Research 38, no. 2 (2011): 89. http://dx.doi.org/10.1071/wr07177.
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Context Mapping the habitat and distribution of a species is critical for developing effective conservation plans. Koala (Phascolarctos cinereus, Phascolarctidae) distribution is constrained by the nutritional and shelter requirements provided by a relatively small number of key tree species in any given area. Identifying these key species provides a practical foundation for mapping koala habitat and prioritising areas for conservation. Aims To determine key tree species for koalas in Noosa Shire (south-eastern Queensland, Australia) as a basis for mapping koala habitat quality. Methods We applied a faecal-pellet survey methodology in 1996/97 to assess evidence of use by koalas of 4031 trees from 96 randomly stratified survey sites across different eucalypt-forest and woodland communities. Results were compared with those from a later survey undertaken in 2001/02 involving 5535 trees from 195 sites that were distributed across broadly similar areas with the aim to investigate aspects of koala landscape ecology. Key results A total of 66.7% of the 1996/97 survey sites contained koala faecal pellets, recorded under 953 eucalypt trees (14 species) and 1670 non-eucalypt trees (27 species). The proportion of trees at a given survey site that had koala faecal pellets at the base ranged from 2.2% to 94.7% (mean = 31.13 ± 2.59% s.e.). For the 2001/02 dataset, koala pellets were found at 55.4% of sites, from 794 eucalypt and 2240 non-eucalypt trees. The proportion of trees with pellets ranged from 3% to 80% (mean = 21.07 ± 1.77% s.e.). Both the 1996/97 and 2001/02 surveys identified the same three tree species (forest red gum, Eucalyptus tereticornis, swamp mahogany, E. robusta, and tallowwood, E. microcorys) as the highest-ranked for koala use in the study area. Three additional species (red mahogany, E. resinifera, small-fruited grey gum, E. propinqua, and grey ironbark, E. siderophloia) were identified in the 1996/97 surveys as key eucalypt species. Of the non-eucalypts in the 1996/97 dataset, coast cypress pine (Callitris columellaris) and broad-leaved paperbark (Melaleuca quinquenervia) ranked highest for use by koalas, followed by pink bloodwood (Corymbia intermedia) and brush box (Lophostemon confertus). White bottlebrush (Callistemon salignus), hard corkwood (Endiandra sieberi), M. quinquenervia and C. intermedia ranked highest in the 2001/02 dataset. The findings showed significantly greater use of larger eucalypts (i.e. 300-mm to >600-mm diameter at breast height). Conclusions The identified key eucalypt species, being the critical limiting resource for koalas, were used to assign koala habitat-quality classes to mapped regional ecosystem types to create a Koala Habitat Atlas (KHA) for Noosa Shire. The combined two highest quality classes based on abundance of the key eucalypt species comprised only 15.7% of the total land area of the Shire. Implications The KHA approach provides a practical and repeatable method for developing koala habitat-suitability mapping for national-, regional- and local-scale conservation and recovery planning purposes.
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Speight, K. N., W. G. Breed, W. Boardman, D. A. Taggart, C. Leigh, B. Rich, and J. I. Haynes. "Leaf oxalate content of Eucalyptus spp. and its implications for koalas (Phascolarctos cinereus) with oxalate nephrosis." Australian Journal of Zoology 61, no. 5 (2013): 366. http://dx.doi.org/10.1071/zo13049.
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Oxalate nephrosis is a leading disease of the Mount Lofty Ranges koala population in South Australia, but the cause is unclear. In other herbivorous species, a common cause is high dietary oxalate; therefore this study aimed to determine the oxalate content of eucalypt leaves. Juvenile, semimature and mature leaves were collected during spring from eucalypt species eaten by koalas in the Mount Lofty Ranges and compared with those from Moggill, Queensland, where oxalate nephrosis has lower prevalence. Total oxalate was measured as oxalic acid by high-performance liquid chromatography. The oxalate content of eucalypts was low (<1% dry weight), but occasional Mount Lofty leaf samples had oxalate levels of 4.68–7.51% dry weight. Mount Lofty eucalypts were found to be higher in oxalate than those from Queensland (P < 0.001). In conclusion, dietary oxalate in eucalypt leaves is unlikely to be the primary cause of oxalate nephrosis in the Mount Lofty koala population. However, occasional higher oxalate levels could cause oxalate nephrosis in individual koalas or worsen disease in those already affected. Further studies on the seasonal variation of eucalypt leaf oxalate are needed to determine its role in the pathogenesis of oxalate nephrosis in koalas.
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Baranowski, Kelsee, Teairah Taylor, Brian Lambert, and Nita Bharti. "Application of Reflectance Ratios on High-Resolution Satellite Imagery to Remotely Identify Eucalypt Vegetation." Remote Sensing 12, no. 24 (December 13, 2020): 4079. http://dx.doi.org/10.3390/rs12244079.
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The scale and accessibility of passive global surveillance have rapidly increased over time. This provides an opportunity to calibrate the performance of models, algorithms, and reflectance ratios between remote-sensing devices. Here, we test the sensitivity and specificity of the Eucalypt chlorophyll-a reflectance ratio (ECARR) and Eucalypt chlorophyll-b reflectance ratio (ECBRR) to remotely identify eucalypt vegetation in Queensland, Australia. We compare the reflectance ratio values from Sentinel-2 and Planet imagery across four sites of known vegetation composition. All imagery was transformed to reflectance values, and Planet imagery was additionally scaled to harmonize across Planet scenes. ECARR can identify eucalypt vegetation remotely with high sensitivity but shows low specificity and is impacted by the density of the vegetation. ECBRR reflectance ratios show similar sensitivity and specificity when identifying eucalypt vegetation but with values an order of magnitude smaller than ECARR. We find that ECARR was better at identifying eucalypt vegetation in the Sentinel-2 imagery than Planet imagery. ECARR can serve as a general chlorophyll indicator but is not a specific index to identify Eucalyptus vegetation with certainty.
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Lourenço, Ana, Dragana Kukić, Vesna Vasić, Ricardo A. Costa, Mirjana Antov, Marina Šćiban, and Jorge Gominho. "Valorisation of Lignocellulosic Wastes, the Case Study of Eucalypt Stumps Lignin as Bioadsorbent for the Removal of Cr(VI)." Molecules 27, no. 19 (September 22, 2022): 6246. http://dx.doi.org/10.3390/molecules27196246.
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The main objective of this work was to assess Eucalyptus globulus lignin as an adsorbent and compare the results with kraft lignin, which has previously been demonstrated to be an effective adsorbent. Eucalypt lignin was extracted (by the dioxane technique), characterised, and its adsorption properties for Cr(VI) ions were evaluated. The monomeric composition of both types of lignin indicated a high content of guaiacyl (G) and syringyl (S) units but low content of p-hydroxyphenyl (H), with an H:G:S ratio of 1:50:146 (eucalypt lignin) and 1:16:26 (kraft lignin), as determined by Py-GC/MS. According to elemental analysis, sulphur (2%) and sodium (1%) were found in kraft lignin, but not in eucalypt lignin. The adsorption capacity of the eucalypt lignin was notably higher than the kraft lignin during the first 8 h, but practically all the ions had been absorbed by both the eucalypt and kraft lignin after 24 h (93.4% and 95%, respectively). Cr(VI) adsorption onto both lignins fitted well using the Langmuir adsorption isotherm model, with capacities of 256.4 and 303.0 mg/g, respectively, for eucalypt and kraft. The study’s overall results demonstrate the great potential of eucalypt lignin as a biosorbent for Cr(VI) removal from aqueous solutions.
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Chauvet, Eric, Eric Fabre, Arturo Elósegui, and Jesús Pozo. "The impact of eucalypt on the leaf-associated aquatic hyphomycetes in Spanish streams." Canadian Journal of Botany 75, no. 6 (June 1, 1997): 880–87. http://dx.doi.org/10.1139/b97-097.
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Aquatic hyphomycete assemblages on decomposing leaf litter of the exotic species Eucalyptus globulus Labill. were compared with those on the native riparian species Alnus glutinosa (L.) Gaertn. in three low-order streams of the Agüera watershed (Basque Country – Cantabria, Spain). These streams contrast by the importance of eucalypt in the riparian vegetation and by the nutrient contents in the water. Neither the total conidial production nor the number of fungal species differed between the two leaf species in any of the streams. Fungal colonization of eucalypt leaves appeared to be delayed by about 2 weeks, probably owing to their high content in inhibitory constituents. While Flagellospora curvula Ingold largely dominated pioneer assemblages on both leaf species, the second most important species, Lunulospora curvula Ingold, exhibited a preference for eucalypt. In the stream surrounded by eucalypt, the fungal diversity was surprisingly lower on eucalypt than on alder. In the stream with higher orthophosphate concentrations, the conidial production was similarly increased on both leaf species. The present data together with recent results from a similar investigation in Portugal suggest a minor impact of eucalypt on the activity and diversity of aquatic hyphomycete leaf-associated assemblages in southern European streams. Key words: aquatic hyphomycetes, eucalypt, alder, leaf litter, stream.
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Vences, Miguel. "Habitat choice of the salamander Chioglossa lusitanica: the effects of eucalypt plantations." Amphibia-Reptilia 14, no. 3 (1993): 201–12. http://dx.doi.org/10.1163/156853893x00408.
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AbstractEvidence is presented that golden-striped salamander Chioglossa lusitanica populations in eucalypt plantations may be subject to two influences. There is a low density of leaf litter invertebrates which are the preferred prey. Substrate choice experiments show that that the salamanders avoid eucalypt leaves as substrates for shelter. A long-term study of Chioglossa populations at two brooks in northern Portugal, however, showed that the numbers at one site did not change notably after plantation with eucalypts in comparison with the other, less altered, locality. Chioglossa is the most abundant amphibian species along water courses in the Spanish province of La Coruña, although eucalypts are planted along most of them.
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Bowman, DMJS, JCZ Woinarski, and KA Menkhorst. "Environmental Correlates of Tree Species Diversity in Stage III of Kakadu National Park, Northern Australia." Australian Journal of Botany 41, no. 6 (1993): 649. http://dx.doi.org/10.1071/bt9930649.
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A quadrat based survey that sampled across the environmental range of the geologically and topographically diverse Stage III of Kakadu National Park, Northern Territory, revealed that the region has a tree flora dominated by the family Myrtaceae, and the genus Eucalyptus in particular. Principal components analysis (PCA) defined three axes of environmental variation: site rockiness, site hydrology and surface soil clay content. The three PCA axes were divided into halves and a 2x2x2 matrix was created to classify eight environments; however, there were quadrats in only seven of the eight possible environments. Kruskal-Wallis one-way ANOVAs showed that there was significant variation of the following variables between the 7 environments: total basal area, tree species richness, proportion tree richness composed of eucalypt species, and proportion of eucalypt richness composed of the four subgenera Blakella, Corymbia, Eudesmia and Symphyomyrtus. Of the most abundant 25 tree species and other common eucalypts only five species (Allosyncarpia ternata, Eucalyptus bigalerita, E. clavigera, E. foelscheana and E. jacobsiana) did not have significant differences in their mean basal area between the seven environments. The above patterns are interpreted as evidence that the savanna is a highly evolved system rather than the product of geologically recent disturbance to a once widespread monsoon rainforest.
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Sampson, JF, SD Hopper, and SH James. "The Mating System and Genetic Diversity of the Australian Arid Zone Mallee, Eucalyptus rameliana." Australian Journal of Botany 43, no. 5 (1995): 461. http://dx.doi.org/10.1071/bt9950461.
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Estimates of parameters of the mixed mating model were made for three populations of the bird-pollinated arid zone eucalypt, Eucalyptus rameliana F. Muell. Levels of outcrossing ((t) over cap) varied significantly between populations from mixed mating with substantial selfing ((t) over cap = 0.54) to almost completely outcrossed ((t) over cap = 0.95). Comparison of single-locus and multilocus estimates suggested that the drop in outcrossing was due to increased self-pollination. The lowest outcrossing rate was attributed to the reduced ability of a population with low numbers of buds to attract bird pollinators. Outcrossing rates in E. rameliana are proposed to be a more direct reflection of pollination than estimates made for mass flowering, i.e. small-fruited eucalypts. The distribution of allozyme diversity in E. rameliana also appeared to reflect the impact of bird pollinators in promoting gene flow as well as the species capacity for outcrossing and introgression. Levels of diversity were comparable with other eucalypts, but the proportion of diversity between populations (GST = 9.2%) was only about half the mean for other eucalypts. Genetic distances between populations were low, but there was same significant differentiation of populations which was attributed to non-random bird migrations. The importance of bird pollination in the mating system and the distribution of genetic diversity in E. rameliana emphasises that enough habitat to support nomadic birds should be preserved in order to conserve this eucalypt species.
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Burrows, W. H., M. B. Hoffmann, J. F. Compton, P. V. Back, and L. J. Tait. "Allometric relationships and community biomass estimates for some dominant eucalypts in Central Queensland woodlands." Australian Journal of Botany 48, no. 6 (2000): 707. http://dx.doi.org/10.1071/bt99066.
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Allometric equations are presented relating stem circumference to branch, leaf, trunk, bark, total above-ground and lignotuber biomass for Eucalyptus crebra F.Muell. (woodland trees), E. melanophloia Sol. Ex Gaerth. (both woodland and regrowth community trees) and E. populnea F.Muell. (woodland trees). There were no significant differences (P > 0.05) between the slopes of individual lognormal regression lines plotting stem circumference against total above-ground biomass for E. crebra, E. melanophloia and E. populnea. Root-to-shoot ratios and leaf area indices were also determined for the stands contributing to each regression. The regressions were then applied to measured eucalypt stems in the associated plant community to give estimates of each stand’s component (eucalypt tree fraction only) biomass per hectare. These eucalypt regressions were next applied to measured stems of each species on a total of 33 woodland sites in which these eucalypts individually contributed > 75% of total site basal area. Above-ground biomass/basal area relationships averaged 6.74 0.29 t m–2 basal area for 11 E. crebra sites, 5.11 0.28 t m–2 for 12 E. melanophloia sites and 5.81 0.11 t m–2 for 10 E. populnea sites. The mean relationship for all sites was 5.86 0.18 t m–2 basal area. The allometric relationships presented at both individual tree and stand levels, along with calculated biomass : basal area relationships, enable ready estimates to be made of above-ground biomass (carbon stocks) in woodlands dominated by these eucalypts in Queensland, assuming individual stem circumferences or community basal areas are known. However, to document changes in carbon stocks (e.g. for Greenhouse Gas Inventory or Carbon Offset trading purposes), more attention needs to be placed on monitoring fluxes in the independent variables (predictors) of these allometric equations.
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Vidaurre, Graziela Baptista, Miguel Pereira, Walter Torezani Neto Boschetti, Rudolf Patt, Jorge Luiz Colodette, Benedito Rocha Vital, and Maria Naruna Felix de Almeida. "NSSC pulping of fast growing trees." Nordic Pulp & Paper Research Journal 33, no. 3 (September 25, 2018): 404–13. http://dx.doi.org/10.1515/npprj-2018-3044.
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Abstract Neutral sulphite semichemical pulping (NSSC) of Schizolobium amazonicum (Paricá), a fast-growing Amazonian tree, was compared with that of Eucalyptus grandis (eucalypt), one of the most important wood sources for the Brazilian pulp industry, and with mixtures of both woods in different proportions (mix). Wood chips prepared from 7-year old trees were steamed, cooked using the NSSC process and defibered in a 12” disc refiner in three stages. The paricá wood produced pulp of lower yield (75 %) than eucalypt (77 %) at 16 % sulfite/150 min/170 °C. The paricá and eucalypt pulps were bleached to about 68 and 74 % ISO brightness, respectively, by the QPFAS sequence. Paricá consumed more energy for refining in comparison with the eucalypt wood. The wood mix produced lower yield and brightness than the single species processed separately.
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Brookhouse, Matthew. "Eucalypt dendrochronology: past, present and potential." Australian Journal of Botany 54, no. 5 (2006): 435. http://dx.doi.org/10.1071/bt05039.
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Dendrochronology has the capacity to provide unique insights into natural vegetation dynamics and yield climatological reconstructions. However, because of a persistent belief that eucalypts are unsuited to dendrochronological analysis, research interest in the genus has been limited. A thorough review of the eucalypt dendrochronological literature reveals that perceived limitations may be locally overcome. However, methodological problems associated with many studies mean that results are often difficult to interpret. Consequently, the dendrochronological potential of the eucalypts remains unresolved. To overcome this, a detailed dendrochronological reconnaissance of the eucalypts, drawing on established datasets, systematic study of individual species and sites and examination of non-width-based tree-ring properties, is recommended.
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Marsh, Karen J., Ian R. Wallis, and William J. Foley. "The effect of inactivating tannins on the intake of Eucalyptus foliage by a specialist Eucalyptus folivore (Pseudocheirus peregrinus) and a generalist herbivore (Trichosurus vulpecula)." Australian Journal of Zoology 51, no. 1 (2003): 31. http://dx.doi.org/10.1071/zo02055.
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The paucity of evidence on eucalypt browsing by common brushtail and common ringtail possums suggests that ringtails preferentially eat foliage from trees within the subgenus Monocalyptus. In contrast, brushtails eat less eucalypt foliage than do ringtails and prefer trees from the subgenus Symphyomyrtus. Trees from these subgenera differ in their defensive chemicals. Both contain tannins but it appears that only the symphyomyrts synthesise formylated phloroglucinol compounds (FPCs). We fed possums foliage from several individual Eucalyptus rossii and E. consideniana, both monocalypts, to avoid the confounding factor of FPCs, and examined the effects of blocking tannins by dipping foliage in polyethylene glycol (PEG). Ringtails and brushtails differed in their abilities to eat foliage from these eucalypts. The ringtails ate much more than did the brushtails and showed a small (about 10%) but significant increase in feeding in response to PEG. The brushtails were reluctant to eat foliage from either eucalypt species but doubled their intake when leaves were coated with PEG. Even so, they still did not eat enough to meet maintenance requirements for energy and nitrogen. Neither ringtails nor brushtails preferred foliage from any individual E. rossii tree, suggesting that all trees were equally defended. However, brushtails preferred foliage from some E. consideniana to others. Monocalypt tannins are clearly important barriers to feeding in brushtail possums, but further research with higher doses of PEG will confirm whether they are the only deterrent chemicals in monocalypt foliage.
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Murphy, Brett P., Adam C. Liedloff, and Garry D. Cook. "Does fire limit tree biomass in Australian savannas?" International Journal of Wildland Fire 24, no. 1 (2015): 1. http://dx.doi.org/10.1071/wf14092.
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Processes allowing coexistence of trees and grasses in tropical savannas have long intrigued ecologists. Early theories focused on climatic controls, but a conceptual model has emerged suggesting that savanna trees are subject to a fire-mediated recruitment bottleneck, with frequent fires preventing recruitment of saplings into the tree layer and maintaining biomass well below its climate-determined upper bound. We propose that this conceptual model has been overemphasised in northern Australia, where tree abundance is more strongly controlled by water availability. The dominant trees, eucalypts, have a remarkable capacity to grow through the ‘fire trap’ to reach fire-resistant sizes. This fire tolerance makes eucalypts relatively unresponsive to management-imposed reductions in fire frequency and intensity. Other trees in these savannas are typically more fire sensitive and respond positively to such management. There are suggestions that savanna fire management could lead to increases in woody biomass, but we contend that if tree biomass is strongly limited by water availability, then potential increases in tree biomass are relatively limited, at least in relation to the dominant eucalypt component. There is potential to increase the biomass of the more fire-sensitive non-eucalypts, but the upper bound of non-eucalypt tree biomass in these eucalypt-dominated systems remains poorly understood.
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Tuller, Juliana, Karla Nunes Oliveira, Jhonathan Oliveira Silva, Maurício Lopes de Faria, Mario Marcos do Espírito-Santo, José Eduardo Serrão, and José Cola Zanuncio. "Glycaspis brimblecombei (Hemiptera: Psyllidae) attack patterns on different Eucalyptus genotypes." PeerJ 5 (October 24, 2017): e3864. http://dx.doi.org/10.7717/peerj.3864.
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Background The red gum lerp psyllid, Glycaspis brimblecombei Moore (Hemiptera: Psyllidae), an eucalypt insect pest from Australia, was reported in Brazil in 2003. This study evaluated damage patterns of this pest on Eucalyptus camaldulensis Dehn (Myrtaceae) and its hybrids E. urophylla X E. camaldulensis (urocam) and E. urophylla X E. grandis (urograndis). In addition, parasitism rates of Psyllaephagus bliteus Riek (Hymenoptera: Encyrtidae) on G. brimblecombei collected on different eucalypt genotypes are reported. Methods Plantation plots of three eucalypt genotypes were evaluated over one year. The eucalypt leaves were collected and examined for attack by G. brimblecombei. Nymph parasitism of G. brimblecombei by P. bliteus was recorded. Results Damage by G. brimblecombei was lower on the hybrid genotypes and on the adaxial surface of the eucalypt leaves. G. brimblecombei egg and nymph density were negatively correlated with monthly rainfall. Nymph parasitism of G. brimblecombei by P. bliteus was low (2.9%) independent of genotype and did not vary throughout the year. Discussion Our data indicate the use of less susceptible eucalypt genotypes (e.g., hybrids) as an alternative to G. brimblecombei management. Because of the current low mortality rates for G. brimblecombei resulting from P. bliteus parasitism, biological control with this natural enemy is not recommended as a management strategy for G. brimblecombei.
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González-Paz, Lorena, Josué Gestido, Cristina Delgado, Nuria Pedrol, and Isabel Pardo. "Short-Term Effect of Eucalyptus Leachates on Green Food Webs in Headwaters." Water 15, no. 1 (December 29, 2022): 115. http://dx.doi.org/10.3390/w15010115.
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Despite the reported allelopathic nature of the Eucalyptus genus, eucalypt leachates have unknown effects on the trophic base of stream green food webs. Eucalypt plantations have increased worldwide, including riparian ecosystems. We aimed to test whether short-term eucalypt leachates might alter water chemistry, periphytic algal biomass and diatoms, and herbivorous invertebrates’ (i.e., scrapers). We studied two oligotrophic and well-preserved headwaters from NW Spain. The experiment followed a before-after control-impact paired (BACIp) design, with weekly sampling before and after eucalypt leaves addition to streams. In the stream with lower discharge, the eucalypt treatments seemed to affect increases in biomass accrual (Chl-a) and diatom assemblages, disfavouring sensitive species (e.g., Eunotia minor and Achnanthidium pyrenaicum). Therefore, the ecological status was reduced from high to good. In the stream with higher discharge, invertebrate assemblages changed with scrapers having their abundances modified in comparison with the control (e.g., Habrophlebia sp. and Elmidae). Results suggest that eucalypt leaves leachates exert toxic effects on periphyton and on diatom and invertebrate assemblages, and this effect might be mediated by discharge. Alterations at the base of stream food webs may compromise their good ecological status. Further studies are necessary to identify whether this toxicity is due to allelopathic processes.
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McCarthy, Michael A., and Laura J. Pollock. "Conserving phylogenetic diversity, with reference to Victorian eucalypts." Proceedings of the Royal Society of Victoria 128, no. 1 (2016): 7. http://dx.doi.org/10.1071/rs16001.
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Preserving the tree of life (i.e. phylogenetic diversity) is increasingly recognised as important in conservation. Australia is a key area for retaining the tree of life because it holds a disproportionately large amount of phylogenetic diversity. We examine the degree to which the phylogenetic diversity of Victorian eucalypts is reserved within conservation areas. Based on modelled distributions of 101 eucalypt species and a phylogeny constructed from four molecular markers, we show that Victoria’s conservation reserve system contains approximately a quarter of the eucalypt phylogenetic diversity. Some species do not exist at all within the reserve system. Large increases in reserved phylogenetic diversity could be achieved with small increases in the area set aside for conservation. Further, we show that any developments within Victoria’s national parks should consider impacts on the reservation of eucalypt phylogenetic diversity.
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Rosa, Daniel Dias, Edson Luiz Furtado, Leonardo Pires Boava, Celso Luis Marino, Edson Seizo Mori, Iraê Amaral Guerrini, Edivaldo Domingues Veline, and Carlos Frederico Wilcken. "Eucalyptus ESTs involved in mechanisms against plant pathogens and environmental stresses." Summa Phytopathologica 36, no. 4 (December 2010): 282–90. http://dx.doi.org/10.1590/s0100-54052010000400002.
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Eucalypt plantation has high economical importance in Brazil; however, it has been attacked by various pathogens under different environmental stress conditions. Disease resistance and survival under unfavorable environmental conditions have revealed that the eucalypt has developed highly efficient defense systems. Here we show the results of the Eucalyptus ESTs Genome Project (FORESTs). Using the expressed sequence tags (ESTs) obtained by the Project, contigs of similar sequences from each cDNA library induced and not induced by stress agents were formed, and cDNA sequences similar to other already known molecules, such as plant-signaling molecules, phytoalexins, lignin biosynthesis pathways, PR-proteins and putative genes corresponding to enzymes involved in the detoxification of reactive oxygen species, were identified. We also present general considerations about the mechanisms of Eucalyptus defense against biotic and abiotic stresses. These data are of extreme importance for future eucalypt breeding programs aimed at developing plants with enhanced resistance against pathogens and environmental stresses.
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Lin, H., T. J. Murray, and E. G. Mason. "Incidence of and defoliation by a newly introduced pest, Paropsisterna variicollis (Coleoptera: Chrysomelidae), on eleven durable Eucalyptus species in Hawke’s Bay, New Zealand." New Zealand Plant Protection 70 (August 8, 2017): 45–51. http://dx.doi.org/10.30843/nzpp.2017.70.26.
Full textAbstract:
In March 2016, an incursion of the paropsine beetle Paropsisterna variicollis (eucalyptus variegated beetle) was detected in the Hawke’s Bay during routine Forest Biosecurity Surveillance. Paropsines cause significant damage to eucalypt plantations in several parts of the world. A survey of three Hawke’s Bay sites containing 11 durable eucalypt species was conducted in January 2017. Defoliation by paropsines, and numbers of eggs, larvae and adults were recorded. Adult Pst. variicollis were observed on all eucalypt species, and were present in larger numbers than Paropsis charybdis in two sites. Eucalyptus bosistoana sustained the greatest defoliation and incidence of eggs and larvae, and E. macrorhyncha the least. Parasitism of Pst. variicollis eggs was observed but the agent was not definitively confirmed. Results indicate Pst. variicollis will exhibit a wide host range in New Zealand but variability observed in the levels of defoliation between species may be linked to heritable traits that can be exploited through current breeding programmes.
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Xiang, W., and J. Bauhus. "Does the addition of litter from N-fixing Acacia mearnsii accelerate leaf decomposition of Eucalyptus globulus?" Australian Journal of Botany 55, no. 5 (2007): 576. http://dx.doi.org/10.1071/bt06083.
Full textAbstract:
Nutrient cycling in mixed-species plant communities may be enhanced in comparison to what might be expected from the component species. In this study, we investigated (1) whether the admixing of nitrogen-rich litter from Acacia mearnsii can accelerate the decomposition of Eucalyptus globulus leaf litter and (2) whether eucalypt litter originating from mixed stands with acacias decomposes faster than litter from pure eucalypt stands. To address the first question, pure and mixed litter was incubated in the laboratory for 110 days at 25°C in the following proportions: 100%E, 75%E : 25%A, 50%E : 50%A, 25%E : 75%A and 100%A, where %E and %A refers to the proportion of eucalypt and acacia in the microcosms, respectively. Since mass loss and N loss of litter in the 50 : 50 mixture was higher than for pure eucalypt but not higher than for acacia, it appears that acacia litter accelerated decomposition of eucalypt litter but not vice versa. Decomposition rates increased with N concentration in the combined litters up to 1.1% N, above that point it remained constant. To address the second question, eucalypt litter from pure and mixed stands was incubated in microcosms. The loss of mass, N and P after 110 days was not different for eucalypt litter originating from mixed (75E : 25A, 50E : 50A, 25E : 75A) and pure (100E) plantations. Together, these studies suggest that admixture of A. mearnsii to E. globulus has the potential to accelerate decomposition and N cycling, and that the species interactions are most pronounced in the 50 : 50 mixture. Mixing of the two species in plantations has so far had no influence on the decomposability of eucalypt litter.
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Booth, Trevor H. "Eucalypts and Their Potential for Invasiveness Particularly in Frost-Prone Regions." International Journal of Forestry Research 2012 (2012): 1–7. http://dx.doi.org/10.1155/2012/837165.
Full textAbstract:
Eucalypts are being considered for biofuel production in the Lower Coastal Plain of the United States. The evolution of eucalypts in Australia has equipped some species to be successful in plantations and has also influenced their potential as invasive species. More than 200 eucalypt species have been evaluated in many countries around the world. Generally eucalypts have proved to have limited invasive potential for a number of reasons, including their poor dispersal capabilities. Two regions with climates similar to the Lower Coastal Plain of the United States are identified in Argentina and China. Frosts, particularly sudden frosts, are an important limitation for eucalypts in these regions, so existing plantations are very limited. However, invasive eucalypts do not appear to be a major problem in other regions of either country. The use of carefully selected frost-tolerant species and the development of genetically modified eucalypts may now open up more frost-affected areas for eucalypt plantations. Some control actions may be necessary and research needs are outlined, but it is concluded that experience in other regions around the world suggests that eucalypts are likely to be a relatively low risk as invasive species in the Lower Coastal Plain.
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Jessen, Brenda L., Geno A. Picchioni, and John G. Mexal. "287 Total Biomass and Ion Accumulaton of Eucalyptus camaldulensis, Hybrid Populus, and Robinia pseudoacacia Irrigated with Saline Municipal Wastewater." HortScience 34, no. 3 (June 1999): 491F—492. http://dx.doi.org/10.21273/hortsci.34.3.491f.
Full textAbstract:
A field study was conducted in 1997 and 1998 in Ojinaga, Chihuahua, Mexico, to compare biomass production potential and ion uptake capacity of seven tree species and clones, Eucalyptus camaldulensis (4016, 4019, and 505), hybrid Populus (029, 197, and 367), and seedlings of Robinia pseudoacacia irrigated with saline municipal wastewater. Total dry biomass production was greatest with poplar clone 367 (657 g) and eucalypt clone 4019 (643 g). Both clones also provided the most aboveground biomass (463 and 528 g, respectively), essentially because of their greater stem biomass (274 and 234 g, respectively). Poplar clone 367 had the highest lateral branch biomass (84 g), followed by eucalypt clone 4019 (75 g). The clones with the greatest leaf biomass were eucalypt clone 4019 (179 g), followed by eucalypt clone 505 (148 g) and poplar clone 367 (145 g). In all tree selections, Cl concentration was highest in the leaves with poplar clone 197 having the highest concentration (>2%), but the lowest subsequent winter survival at just 55%. The tree with the second lowest survival rate, poplar clone 029 (76%), also had the second highest Cl concentration in its leaves, almost 1.5% Cl. Eucalypt clones 4019 and 4016 accumulated the most total Cl in its tissues (327 and 236 g per tree, respectively) followed by poplar clone 029 (216 g per tree). Eucalypt clone 4019 accumulated the most Na in its tissues (109 g per tree) followed by poplar clone 367 (74 g per tree). In conclusion, poplar clone 367 and eucalypt clone 4019 seem to be sufficiently salt-tolerant for these saline conditions, having high survival, growth, and biomass capacity and perform well under high biomass-generating, short rotation conditions. Eucalypt clone 4019 is also an effective accumulator of Cl and Na ions and may be the most suitable tree for the remediation of salt-affected land in these experimental conditions.
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Southerton, Simon G. "Early flowering induction and Agrobacterium transformation of the hardwood tree species Eucalyptus occidentalis." Functional Plant Biology 34, no. 8 (2007): 707. http://dx.doi.org/10.1071/fp07118.
Full textAbstract:
Investigation of the genes controlling flowering in eucalypts is hindered by the lack of an early-flowering genotype. Induction of early flowering was studied in five provenances of Eucalyptus occidentalis Endl. sourced from throughout its geographic range. Seedlings initiated flowers from 13 weeks after sowing when grown under optimal conditions with a 16-h photoperiod. By 16 weeks, seedlings from four widely dispersed provenances had initiated floral buds, suggesting that competence to flower early is a common characteristic of the species. The different provenances displayed considerable variation in seedling growth rate. Elevated levels of CO2 had no effect on seedling growth rate, but were associated with delayed flowering. Transformation experiments demonstrated that E. occidentalis is susceptible to Agrobacterium-mediated transformation, in common with several other eucalypt species. E. occidentalis may be a valuable experimental species for molecular and other flowering studies in eucalypts.
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Silva, Ximena, Jolanda Roux, and Fred O. Asiegbu. "Diseases of Eucalypts in Paraguay and First Report of Teratosphaeria zuluensis from South America." Forests 11, no. 10 (September 24, 2020): 1035. http://dx.doi.org/10.3390/f11101035.
Full textAbstract:
Background and objectives: The global forest economy is threatened by eucalypt pathogens which are often latent or cryptic species that escape common quarantine and detection methods. Plantation forestry using eucalypts is of considerable importance to Paraguay, but knowledge regarding the pests and diseases affecting these plantations is limited. This study identified fungal diseases present in these plantations. Materials and Methods: We surveyed eucalypt plantations in four provinces in Paraguay and collected material from diseased trees for identification of the causal agents. The samples were analyzed using a combination of morphological and molecular methods. Results: Diseases encountered included Botryosphaeria stem canker, Calonectria leaf blight, Chrysoporthe stem canker, myrtle/eucalypt rust, Coniella leaf spot, heartwood rot and Teratosphaeria stem canker. Contrary to expectations, the causal agent of Teratosphaeria stem canker was identified as Teratosphaeria zuluensis (M.J. Wingf., Crous & T.A. Cout.) M.J. Wingf. & Crous and not Teratosphaeria gauchensis (M.-N. Cortinas, Crous & M.J. Wingf.) M.J. Wingf. & Crous, that is commonly documented for the South American region. Conclusions: This study updates the knowledge on forest fungal pathogens in Paraguayan eucalypt plantations and is the first report of T. zuluensis in Paraguay and in South America.
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Manning, R., and M. Harvey. "Fatty acids in honeybee-collected pollens from six endemic Western Australian eucalypts and the possible significance to the Western Australian beekeeping industry." Australian Journal of Experimental Agriculture 42, no. 2 (2002): 217. http://dx.doi.org/10.1071/ea00160.
Full textAbstract:
Western Australian eucalypt pollens in this research have low levels of lipid (0.59–1.9%) when compared with many other plant species that have evolved alongside the European honeybee. Eucalypt-pollen lipid was dominant in linoleic acid (35.7–48%). The six other major fatty acids that were present in the lipid were myristic, palmitic, stearic, oleic, linolenic and arachidic acids. Linoleic acid was dominant in eucalypt pollen at average concentrations of 2.77–5.81 mg/g pollen. These results could be of significance to the Australian beekeeping industry in refining disease-management strategies in the light that other researchers have found that 2 economically damaging bee diseases (EFB and AFB) are inhibited by certain concentrations of the acid. Redgum- or marri (Corymbia calophylla)-pollen lipid was also dominated by 2 other known antibacterial fatty acids: myristic (0.25 mg/g pollen) and linolenic (1.06 mg/g pollen), when compared with the other eucalypts studied.
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Johnstone, Denise, Peter Ades, Gregory Moore, and Ian Smith. "Predicting Wood Decay in Eucalypts Using an Expert System and the IML-Resistograph Drill." Arboriculture & Urban Forestry 33, no. 2 (March 1, 2007): 76–82. http://dx.doi.org/10.48044/jauf.2007.009.
Full textAbstract:
The evaluation of decayed wood in a tree trunk is essential for hazard tree assessment in arboriculture. In this study, an IML-Resistograph was highly successful as a field instrument in its ability to locate and predict the presence of decay in the trunk wood of eucalypts. A system for using the IML-Resistograph to estimate the area of decay in the cross-section of a eucalypt was evaluated for field use. The data from the IML-Resistograph F300S can be used as part of an expert system to estimate the area of wood decay in a cross-section of a standing eucalypt.
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Kelley, G., A. P. O'Grady, L. B. Hutley, and D. Eamus. "A comparison of tree water use in two contiguous vegetation communities of the seasonally dry tropics of northern Australia: the importance of site water budget to tree hydraulics." Australian Journal of Botany 55, no. 7 (2007): 700. http://dx.doi.org/10.1071/bt07021.
Full textAbstract:
Tree water use in two contiguous communities (eucalypt open-forest and Melaleuca paperbark forest) was measured in tropical Australia, over a 2-year period. The aims of the study were to (1) quantify daily and seasonal patterns of water use in each community, (2) compare patterns of water use among the communities and (3) compare relationships among tree size, sapwood area and water use within the two contrasting vegetation communities. Access to deep soil water stores and the effect of run-on from the eucalypt forest resulted in a relatively high pre-dawn water potential throughout the year, particularly for Melaleuca forest. There were no differences in daily rates of water use, expressed on a sapwood area (Q s) basis, between the two eucalypt species examined (Eucalyptus miniata Cunn. Ex Schauer and E. tetrodonta F.Muell) at any time in the eucalypt forest. For both the eucalypt and Melaleuca forests, there was less seasonal variation in water use expressed on a leaf area (Q l) basis than on a Q s basis, and neither year nor season were significant factors in Q l. In the mono-specific Melaleuca forest, Q s was not significantly different between years or seasons. Water use on a Q l basis was similarly not significantly different between years or seasons in the Melaleuca forest. Leaf area index (LAI) of the eucalypt forest was about half of that of the Melaleuca forest throughout the year but sapwood area per hectare was 33% larger in the eucalypt than the Melaleuca forest, despite the basal area of the Melaeuca forest being almost double that of the eucalypt forest. There was no significant difference in stand water use (mm day–1) between eucalypt and Melaleuca forests during 1998; however, in 1999 Melaleuca stand water use was larger than that of the eucalypt forest. Because of the enhanced dry-season availability of water in the Melaleuca forest and its larger LAI, average annual water use of the Melaleuca forest was almost 60% larger than that of the eucalypt forest. Despite differences in Q l, Q s and annual water use between forests, the ratio of LAI to stand water use was similar for all seasons in both forests. The applicability of ‘universal rules’ linking tree water use and tree hydraulics and the importance of ecosystem location on site water budgets and plant adaptations are discussed.
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Walden, L. L., R. J. Harper, D. S. Mendham, D. J. Henry, and J. B. Fontaine. "Eucalyptus reforestation induces soil water repellency." Soil Research 53, no. 2 (2015): 168. http://dx.doi.org/10.1071/sr13339.
Full textAbstract:
There is an increasing interest in eucalypt reforestation for a range of purposes in Australia, including pulp-wood production, carbon mitigation and catchment water management. The impacts of this reforestation on soil water repellency have not been examined despite eucalypts often being associated with water repellency and water repellency having impacts on water movement across and within soils. To investigate the role of eucalypt reforestation on water repellency, and interactions with soil properties, we examined 31 sites across the south-west of Western Australia with paired plots differing only in present land use (pasture v. plantation). The incidence and severity of water repellency increased in the 5–8 years following reforestation with Eucalyptus globulus. Despite this difference in water repellency, there were no differences in soil characteristics, including soil organic carbon content or composition, between pasture and plantation soils, suggesting induction by small amounts of hydrophobic compounds from the trees. The incidence of soil water repellency was generally greater on sandy-surfaced (<10% clay content) soils; however, for these soils 72% of the pasture sites and 31% of the plantation were not water repellent, and this was independent of measured soil properties. Computer modelling revealed marked differences in the layering and packing of waxes on kaolinite and quartz surfaces, indicating the importance of interfacial interactions in the development of soil water repellency. The implications of increased water repellency for the management of eucalyptus plantations are considered.
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BURCKHARDT, DANIEL, KEVIN FARNIER, DALVA L. QUEIROZ, GARY S. TAYLOR, and MARTIN J. STEINBAUER. "Ctenarytaina bipartita sp. n. (Hemiptera, Psylloidea), a new eucalypt psyllid from Southeast Australia." Zootaxa 3613, no. 6 (February 14, 2013): 589–96. http://dx.doi.org/10.11646/zootaxa.3613.6.5.
Full textAbstract:
Ctenarytaina bipartita sp.n., associated with Eucalyptus kitsoniana and E. viminalis, is described from the Australian Capital Territory, New South Wales, Tasmania and Victoria. It differs from other described Ctenarytaina species in the paramere which bears a small posterior lobe. Taxonomically relevant morphological details are illustrated and the species is diagnosed from other eucalypt inhabiting congeners. Information on the biology is also given. C. bipartita has the po-tential to become an exported pest species to countries with significant eucalypt plantations.
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Dias, T. K. R., E. M. Pires, A. P. Souza, A. A. Tanaka, E. B. Monteiro, and C. F. Wilcken. "The beetle Costalimaita ferruginea (Coleoptera: Chysomelidae) in Eucalyptus plantations in transition area of Amazon and Cerrado Biomes." Brazilian Journal of Biology 78, no. 1 (May 25, 2017): 47–52. http://dx.doi.org/10.1590/1519-6984.03916.
Full textAbstract:
Abstract Costalimaita ferruginea (Coleoptera: Chrysomelidae) attacks Eucalyptus plants causing severe damage through netting of the leaves. Recently, this Coleoptera has been reported attacking Myrtaceae in Mato Grosso State and, studies about the occurrence of this beetle in commercial plantations of eucalypts has been the subject of researchers through monitoring programmes in the forest protection area. With the beginning of the rainy season, adults were observed causing damage in eucalypt plantations in four cities that are part of the transition region of Amazon and Cerrado Biomes. The spots where these insects were observed are located in Feliz Natal, Lucas do Rio Verde, Sorriso and Vera. The purpose of this study was to report the new occurrences and to characterize the attack period of the beetle C. ferruginea in Eucalyptus plantations in Middle-North region of Mato Grosso State, region of Biomes Transition.
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Semple, WS, and TB Koen. "Effect of Seedbed on Emergence and Establishment From Surface Sown and Direct Drilled Seed of Eucalyptus Spp. And Dodonaea Viscosa." Rangeland Journal 19, no. 1 (1997): 80. http://dx.doi.org/10.1071/rj9970080.
Full textAbstract:
In some areas the increase of woody plants is a problem whereas in others, the lack of regeneration is viewed with a similar degree of concern. The experiments described in this paper were an attempt to further understand factors affecting regeneration of woody plants. The effect of seedbed on the emergence and survival of hopbush (Dodonaea viscosa ssp. angustissima) and on several species of Eucalyptus was evaluated at two sites in the Central West of New South Wales. Seed was sown in two springs, two summers and two autumns from 1990 to 1992 and seedlings monitored for 12 months after sowing. Seedbeds compared were prepared by cultivation, scalping, burning, applying herbicide (glyphosate) and mowinglgrazing (control). Following failure of surface sowing in spring 1990 and summer 1990191 due to poor seasonal conditions, all subsequent experiments included direct drilled controls. Emergents were recorded in most treatments in the four succeeding seasons but hopbush and eucalypts responded differently to treatments. Numbers of hopbush emergents and seedlings after 12 months were consistently higher following direct drilling into scalped seedbeds. In contrast, the maximum number of eucalypt emergents was not consistently associated with any seedbed type, though emergence was generally higher following direct drilling. However, higher numbers of eucalypt seedlings were present in scalped plots after 12 months. It was concluded that weed control following emergence was the main effect of seedbed preparation on the number of eucalypt seedlings present after 12 months. Though this also applied to hopbush. seedbeds which provided the opportunity of seed burial enhanced emergence. This was believed to be due to the breaking of seed dormancy.
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Coutinho, T. A., M. J. Wingfield, A. C. Alfenas, and P. W. Crous. "Eucalyptus Rust: A Disease with the Potential for Serious International Implications." Plant Disease 82, no. 7 (July 1998): 819–25. http://dx.doi.org/10.1094/pdis.1998.82.7.819.
Full textAbstract:
Eucalyptus spp. are propagated extensively as non-natives in plantations in many parts of the tropics and sub-tropics. A number of diseases result in serious losses to this economically important forest resource. Eucalyptus rust, caused by Puccinia psidii, is one such example. The economic losses due to this disease are the result of infections of seedlings, young trees, and coppice. P. psidii occurs predominately in Central and South America, but reports of a similar rust are known from other areas. Eucalyptus rust is a remarkable disease in that the pathogen is not known on eucalypts in their centers of origin. It has apparently originated on native Myrtaceae in South America and is highly infective on some Eucalyptus spp. planted there. P. psidii causes one of the most serious forestry diseases in Brazil and is considered to be the most serious threat to eucalypt plantations worldwide. Advances in eucalyptus rust research are reviewed here, with a focus on topics such as distribution, host range, pathogen specialization, symptomatology, etiology, epidemiology, and control.
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Adams, Felicity, Paul Reddell, Michael J. Webb, and Warren A. Shipton. "Arbuscular mycorrhizas and ectomycorrhizas on Eucalyptus grandis (Myrtaceae) trees and seedlings in native forests of tropical north-eastern Australia." Australian Journal of Botany 54, no. 3 (2006): 271. http://dx.doi.org/10.1071/bt05028.
Full textAbstract:
Eucalypts have been shown to form both arbuscular mycorrhizas (AM) and ectomycorrhizas (ECM) in glasshouse experiments. Little is known, however, about the relative dominance of these two mycorrhiza types on individual eucalypt species across their natural range. This study examined mycorrhizal colonisation levels of Eucalyptus grandis Hill ex Maiden roots at 29 sites representing a broad range of wet sclerophyll forest types in the wet tropics of north-eastern Australia. Adult E. grandis trees sampled in situ were invariably heavily ectomycorrhizal, with 76–100% fine root length colonised (% RLC). There were comparatively low levels of AM, with typically less than 10% RLC. Seedling E. grandis grown in intact soil cores from the field sites under glasshouse conditions had lower total levels of mycorrhiza formation compared with adult trees, with more variable ECM formation (10–95% RLC) and more extensive AM formation (10–40% RLC). There were no apparent trends in mycorrhiza formation across different soil parent material, rainfall or vegetation categories used. The current research suggests that arbuscular mycorrhizas are more prominent on seedlings, whereas ectomycorrhizas predominate in adult trees of E. grandis. Possible reasons for these differences and a comparison with other studies of eucalypt mycorrhizas under natural conditions are presented.
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Taylor, RJ, and NM Savva. "Use of Roost Sites by Four Species of Bats in State Forest in South-Eastern Tasmania." Wildlife Research 15, no. 6 (1988): 637. http://dx.doi.org/10.1071/wr9880637.
Full textAbstract:
Roosting requirements and movements between foraging areas and roost sites were studied in Eptesicus regulus, E. sagittula, Chalinolobus morio and Nyctophilus geoffroyi in an area of artificially regenerated eucalypt (Eucalyptus) forest surrounded by mature eucalypt forest. Movements between traps and roost sites were normally about 1 km, with the maximum distance recorded being 4.8 km for a female N. geoffroyi. Different species of eucalypts were used as roost sites in proportion to their occurrence in the forest. However, large trees over 80 cm d.b.h. were favoured. There was no tendency to avoid roost sites close to the ground. Spaces used as roost sites had one dimension little greater than the bat itself. Five types of roost sites were distinguished: in fissures, inside burnt-out boles, in hollows, under bark and on the ground. Individuals changed roost sites frequently but roosts used by any one individual were in the same general vicinity. The factors associated with production of roost sites in trees were: large size, overmaturity, death, rot and fire. No bats were found to roost in regenerated forest. Patches of mature forest will need to be retained to ensure a shortage of roosts does not occur as more areas of mature forest are converted to production forest.