Academic literature on the topic 'E. melliodora-E. blakelyi'

The effects of temperature and light were examined on the germination of 14 seedlots of 10 Eucalyptus species, which are important for revegetation of native communities in north-western New South Wales. The species tested were E. albens, E. blakelyi, E. chloroclada, E. dealbata, E. camaldulensis, E. melanophloia, E. melliodora, E. pilligaensis, E. populnea and E. sideroxylon. Species were subjected to three alternating day/night temperatures (15/5, 25/15 and 35/25°C), representing winter, spring/autumn and summer conditions, respectively, and two light treatments (light/dark or dark), in growth cabinets. Limited quantities of seed of most seedlots prevented full factorial combinations of most treatments. Overall germination was high but varied significantly between species and seedlots within species. Differences were small, but light combined with winter or spring/autumn temperatures resulted in higher average germination (96%) than darkness and summer temperatures (93%). Seedlots of E. chloroclada, E. blakelyi, E. camaldulensis, E. sideroxylon, E. melliodora and E. melanophloia germinated consistently well under all treatment conditions, whereas germination in seedlots of E. albens, E. dealbata, E. melliodora, E. pilligaensis and E. populnea varied with treatments. Germination of small seeds was higher in the presence of light whereas larger seeds germinated better in continuous darkness. The time to first germination was three times faster under summer and spring/autumn temperatures than winter temperatures. In conclusion, temperature and light can significantly impact germination percentage and rate, depending on the species and provenances, and therefore should be considered in planning restoration projects in both nursery and field.

We examined the potential of direct-seeding Eucalyptus species to revegetate the vertosol (‘cracking clay’) soils that characterise the floodplains of north-western New South Wales. We investigated the influence of sowing depth (0, 6, 12 and 20 mm) and three soil-moisture scenarios (dry, moist and flooded) on seedling emergence of seedlings of six species of Eucalyptus with a range of seed sizes (E. blakelyi, E. camaldulensis, E. melanophloia, E. melliodora, E. pilligaensis and E. populnea). We used cracking clay soil from the region in a glasshouse environment. Seedling emergence was low despite high seed viability and provision of optimum temperatures and soil moisture conditions. All six species exhibited greatest emergence when sown at 0–6-mm depth, with seed size being less important than moisture (except under dry conditions) and proximity to the surface. Species responded differently to the three watering treatments. Eucalyptus melanophloia exhibited greatest emergence in the ‘dry’ watering treatment. The floodplain species, E. camaldulensis, E pilliganesis and E. populnea, had the greatest emergence under flood conditions. Eucalyptus blakelyi and E. melliodora exhibited intermediate emergence in relation to all three soil-moisture regimes. Although the direct seeding of these species in vertosol soils in the region may be successful on occasion, windows of opportunity will be infrequent and the planting of seedling tubestock will be more reliable for revegetation.

Considerable areas of remnant native vegetation have been fenced in the last decade to manage grazing by domestic stock. This study investigated vegetation condition in comparative fenced and unfenced remnant vegetation in the mid–upper Murrumbidgee and Lachlan catchments in south-eastern Australia. Native species richness, native groundcover and overstorey regeneration were higher at fenced than at unfenced sites. Area of bare ground was lower at fenced sites. Exotic groundcover did not differ between fenced and unfenced sites. Native species richness was higher at sites fenced for longer and with no stock grazing; neither native nor exotic groundcover at fenced sites was related to time since fencing or stock grazing pressure. Some tree species regenerated at both fenced and unfenced sites (Blakely’s red gum, Eucalyptus blakelyi; tumbledown gum, E. dealbata, long-leaved box, E. goniocalyx; red stringbark, E. macrorhyncha), some regenerated at few fenced and few unfenced sites (white box, E. albens; yellow box, E. melliodora) and some regenerated at fenced sites but not at unfenced sites (grey box, E. microcarpa; mugga ironbark, E. sideroxylon; white cypress pine, Callitris glaucophylla). Although less robust than pre- and postfencing monitoring, the comparisons reported here provide a logistically feasible and relatively inexpensive assessment of effects of the sizeable public investment in fencing on vegetation condition.

Dryland salinity is considered a significant and increasing threat to sustainable land management and biodiversity across large parts of temperate Australia. However, there is little information on the extent of this threat to terrestrial ecosystems in south-eastern Australia. This paper provides a quantitative assessment of the extent of dryland salinity in remnant native woody vegetation in the agriculture-dominated landscape of the Boorowa Shire located in the South West Slopes bioregion of south-eastern Australia. The amount and type of native woody vegetation in the Boorowa Shire affected by dryland salinity was assessed by analysing the extent of overlap between the following three spatial data layers: (1) woody vegetation mapping derived from high-resolution satellite imagery, (2) existing vegetation community mapping predicted from field data and expert opinion and (3) existing dryland salinity outbreak mapping derived from air photo interpretation and filed verification. There were more than 6000 patches of salt outbreak in woody vegetation in the Boorowa Shire, 383 (6%) of which were 1 ha or larger in area. Almost 2000 ha of woody vegetation were affected by dryland salinity, representing ~3% of the extant native woody vegetation in the Boorowa Shire. The vegetation type with the largest total area affected by dryland salinity was yellow box (Eucalyptus melliodora Cunn. Ex Schauer)–Blakely’s red gum (E. Blakelyi Maiden) woodland. As a proportion of their current extent, vegetation communities lower in the landscape were significantly more affected than those higher up the topographic sequence, with 14% of riparian communities and nearly 6% of yellow box–Blakely’s red gum woodland exhibiting symptoms of dryland salinity. About 1% of white box (E. albens Benth) woodland, and of hill communities which are on mid- and upper slopes, were affected. The pattern of salinity outbreaks in relation to landscape position and vegetation type is significant for biodiversity conservation because the vegetation communities most affected by salinisation are those most heavily cleared and modified post-European settlement. Throughout the South West Slopes of New South Wales, remnants of riparian communities and yellow box–Blakely’s red gum woodland are highly cleared, fragmented and degraded. Dryland salinity represents an additional threat to these vegetation communities and their component species. Salinisation of woodland ecosystems poses significant problems for land managers. The long-term viability of these woodland remnants needs to be considered when allocating limited public funds for woodland conservation, whether on private land or in formal reserves.

The bird communities of six riparian woodland sites are described and compared with those of eight terrestrial woodland sites in the Central Tablelands near Bathurst, New South Wales, Australia. Riparian woodland, where still present in the Central Tablelands, is dominated by either relatively narrow strips of Casuarina cunninghamiana along stream banks or the less restricted Angophora floribunda trees associated with Eucalyptus melliodora?E. blakelyi woodlands. Four of the riparian sites were located within cleared agricultural land and two were located within a relatively large nature reserve. Bird censuses along a strip transect were conducted twice per season from spring 1993 to summer 1996. The riparian woodland communities contained within the cleared landscape of the Bathurst basin were found to support a diverse avifauna, a mix of woodland-forest and species associated with agricultural landscapes. Extensive observations of individual birds at riparian sites indicate that the tree canopy is the most widely used microhabitat stratum. While native riparian woodlands are generally degraded, their connectivity and stabilizing function (actual or potential) identifies them as a critical landscape component in maintenance or restoration programmes. Hence it is suggested that riparian strips could form the basis for rehabilitation initiatives within this landscape. Fenced plantings of endemic tree species supplemented by native understorey species could be linked with existing vegetation to enhance landscape connectivity. It is crucial that landholders become aware of the importance of riparian vegetation for nature conservation and stream stabilization. Incentives should be provided to landholders to encourage these areas to be fenced from stock in order to protect them from further degradation in a significantly disturbed ecosystem.

Abstract A description is provided for Mycosphaerella cryptica. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Eucalyptus agglomerata, E. baxteri, E. bicostata, E. blakelyi, E. bosistoana, E. botryoides, E. bridgesiana, E. brookeriana, E. camaldulensis, E. camphora, E. cladocalyx, E. consideniana, E. cypellocarpa, E. dalrympleana, E. delegatensis, E. dendromorpha, E. diversicolor, E. dives, E. dunnii, E. elata, E. fastigata, E. fraxinoides, E. globoidea, E. globulus, E. gomphocephala, E. haemastoma, E. goniocalyx, E. gunnii, E. macrorhyncha, E. marginata, E. melliodora, E. micrantha, E. microcorys, E. muellerana, E. nitens, E. nitida, E. obliqua, E. ovata, E. pauciflora, E. phaeotricha, E. polyanthemos, E. quadrangulata, E. radiata, E. regnans, E. saligna, E. sideroxylon, E. sieberi, E. smithii, E. tereticornis, E. viminalis (61, 7183). DISEASE: Leaf spots, cankers on shoots, twigs and petioles, causing leaf drop and twig die-back of Eucalyptus. GEOGRAPHICAL DISTRIBUTION: Australia, New Zealand. TRANSMISSION: Pseudothecia require humidities reaching saturation for ascospore release. Spores are wind-borne (61, 7182).

This study considered the influence of exotic shrubs on birds in urban patches of Yellow Box- Blakely's Red Gum (E. melliodora-E. blakelyi) woodlands in the Australian Capital Territory, Canberra. The aim of this research was to identify native and exotic birds that have their abundance influenced by exotic shrubs. The purpose of this work was to provide more information to managers of this woodland about the potential impacts of weed control on birds living in woodland reserves adjacent to suburban areas. Birds were sampled between 1996 and 1998 using the twenty minute area-search method to derive estimates of bird abundance. Around 680 twenty minute area-searches were completed, with 665 of these undertaken at 12 two hectare plots with varying levels of exotic shrub cover over a period of ten months. The abundance of birds for each of the ten months sampled were compared by pooling sites into four classes of exotic shrub cover. Classes of exotic shrub cover were nil, light, moderate and dense. Seasonal inferences were drawn from non-parametric analysis of variance. Non-parametric measures of association were used to test for correlation between the mean abundance of bird species at different woodland sites and percentage foliage estimates of exotic shrub cover. Percentage foliage estimates of native shrub cover were included in tests for correlation between bird abundance and exotic shrub cover by applying partial measures of association. To support statistical information, observations of birds in exotic shrub cover were also recorded. In one woodland site birds were sampled before and after the removal of exotic shrub cover. No statistical tests were applied to these samples because of a lack of replication; however, descriptive graphs of the abundance of selected birds following weed control are presented. To investigate the effect that exotic shrub invasion may have on the composition of bird assemblages in woodland cluster analysis and ordination of the 12 sites using the mean abundance of the 75 species recorded between July 1997 and June 1998 were also undertaken. The presence of exotic shrub cover in E. melliodora-E. blakelyi woodland in Canberra was found to have differential effects on bird abundance. Wrens, finches, thornbills, whistlers and pigeons were more abundant in woodland sites where exotic shrubs were present when compared to sites with no or little exotic shrub cover. Fruit-eating birds, such as Silvereyes (Zosterops lateralis), Pied Currawong (Strepera graculina) and Crimson Rosella (Platycercus elegans), were more abundant in woodland with exotic shrubs in winter and autumn when these shrubs provided food in the form of berries. The abundance of fruit-eating birds, and wrens and finches was reduced in a single woodland site following the removal of most of the exotic shrub cover. The Common Blackbird (Turdus merula) was the only exotic bird which showed a strong association with exotic shrubs in woodland, while the Laughing Kookaburra (Dacelo novaeguineae) was negatively correlated with exotic shrub cover, possibly because prey is harder to detect and capture in woodland with a shrubby understorey. Cluster analysis and ordination of the 12 woodland sites did not group sites into the four experimental classes used to undertake analysis of variance. Multivariate analysis, however, did reveal that seasonal peaks in the abundance of fruit eating birds affected the composition of bird assemblages by increasing the mean abundance of these birds in densely invaded sites. Similarly, structural differences in the understorey resulted in some birds being more abundant in woodland sites invaded by exotic shrubs when compared to sites lacking a shrubby understorey. The distance between some sites confirmed this stark difference in bird life when plotted in three dimensions. The results of this study suggest that exotic shrubs add food and structural complexity to woodland habitat. Benefits of structural complexity for small native birds in woodland include nest sites and protection from predators. These benefits may operate at certain thresholds of invasion, as the woodland site with the densest level of exotic shrub invasion showed a slight decrease in the number of wrens and finches. Adverse impacts from exotic shrub invasion may include reduced open ground in which to forage and loss of floristic diversity in the understorey. In effect, exotic shrubs add and remove resources in woodland habitat, benefiting some bird species and limiting others. These findings suggest that the removal of exotic shrub cover in woodland located in urban landscapes simplifies the structural complexity of the understorey, reducing the quality of habitat for some birds. Thus, adverse impacts on biodiversity arising from the invasion of exotic shrubs in woodland need to be considered against the important role that a diverse bird population has in maintaining ecosystem function.