Literatura científica selecionada sobre o tema "Wheat Planting time"

This article describes in detail the influence of sowing dates on the growth, development and productivity of various varieties of winter wheat. Wheat occupies a special place among grain crops in terms of nutritional value and yield. It is known that Uzbekistan, winter wheat is saturated with a vital factor - light. On average, 2,500-3,000 hours of sunshine per year fall on the soil of our country. Therefore, in agriculture, it is possible to determine the sowing time, which corresponds to the biological properties of winter wheat. Wheat bread is superior to other products in its deliciousness, nutritional value and ease of digestion.

Tomatoes (Lycopersicon esculentum Mill.) were grown in conventional tillage (CT), rye (Secale cereale L.) mulch no tillage (RNT), and wheat (Triticum aestivum L.) mulch no tillage (WNT). Either germinated seeds (GS) or raw seeds (RS) were fluid drilled on several dates in 1981 and 1982. Tomato stands in no tillage (NT) generally were equal to or higher than in CT, and stands improved with later plantings in each year. Plant stands were unaffected by GS and RS. Time to 50% emergence (T50) was up to 4 days less in NT than in CT and 2 to 3 days less from GS than RS. Yields with CT were twice as high as those with NT for early planting dates. Yields decreased in CT with successive planting dates to levels equal to NT plantings. Use of GS increased fruit yields as compared to RS, regardless of the planting date.

Limited water resources restrict winter wheat grain yield and quality in the Huang-Huai-Hai Plain of North China, and establishing optimal planting patterns according to crop water requirements is the key factor for achieving rational water use. In this paper, 4 planting patterns were applied, namely, uniform row (30 cm; traditional pattern), wide (40 cm)-narrow (20 cm) row, furrow (double lines in the furrow with 20 cm spacing, and 40 cm between furrows), and seed bed (double lines on the bed with 20 cm spacing, and 40 cm between beds). Each planting pattern was irrigated twice during the jointing and heading stages, and total irrigation water was controlled at 120 mm. Grain yield was significantly (LSD, P < 0.05) higher in the furrow planting pattern than in the uniform row, wide-narrow row, and seed bed planting patterns, by 73.4, 64.3, and 53.4 g/m², respectively, in 2004–2005 and by 54.3, 42.6, and 30.2 g/m², respectively, in 2005–2006, mainly because of a significant (LSD, P < 0.05) increase in the spike and kernel numbers. These results were caused by changes in the contribution of dry matter remobilization to grain yield (CDMRG); the CDMRG was higher in the furrow planting pattern than in the uniform row, wide-narrow row, and seed bed planting patterns by 5.1%, 4.3%, and 2.9%, respectively. Gliadin and glutenin contents in the furrow planting pattern were 4.67% and 5.85%, respectively, and were significantly (LSD, P < 0.05) higher than those in the uniform row, wide-narrow row, and seed bed planting patterns; however, the furrow planting pattern had no significant (LSD, P < 0.05) effect on albumin and globulin contents. Dough development time (DDT) and dough stable time (DST) in the furrow planting pattern were 5.6 min and 8.8 min, respectively; they were significantly (LSD, P < 0.05) improved compared to those in the uniform row, wide-narrow row, and seed bed planting patterns; however, there were no significant (LSD, P < 0.05) differences in dough breakdown time (DBT) between any of the planting patterns. These results suggest that the furrow planting pattern combined with deficit irrigation during the jointing and heading stages can be applied to winter wheat production in the Huang-Huai-Hai Plain of North China.

SummaryIn the wheat–sugarcane rotation, which covers more than half of the growing area in subtropical India, planting of sugarcane is delayed until after the wheat harvest in April–May. This allows little time for the sugarcane to produce tillers and so results in smaller millable cane populations and yields than those from more timely (February–March) plantings. This study considers techniques such as ring and trench planting which might allow a high seed rate to compensate for reduced tillering. Yields obtained using these systems were about 20 t ha−1 greater than from the conventional flat planting method, because of a better distribution of primary shoots from the parent sett and reduced plant competition during the early stage of growth. The cost of cane production was greatest with the ring system and least with the conventional planting method but deep trenches gave the best net return.

Monitoring spatio-temporal changes in winter wheat planting areas is of high importance for the evaluation of food security. This is particularly the case in China, having the world’s largest population and experiencing rapid urban expansion, concurrently, it puts high pressure on food demands and the availability of arable land. The relatively high spatial resolution of Landsat is required to resolve the historical mapping of smallholder wheat fields in China. However, accurate Landsat-based mapping of winter wheat planting dynamics over recent decades have not been conducted for China, or anywhere else globally. Based on all available Landsat TM/ETM+/OLI images (~28,826 tiles) using Google Earth Engine (GEE) cloud computing and a Random Forest machine-learning classifier, we analyzed spatio-temporal dynamics in winter wheat planting areas during 1999–2019 in the North China Plain (NCP). We applied a median value of 30-day sliding windows to fill in potential data gaps in the available Landsat images, and six EVI-based phenological features were then extracted to discriminate winter wheat from other land cover types. Reference data for training and validation were extracted from high-resolution imagery available via Google Earth™ online mapping service, Sentinel-2 and Landsat imagery. We ran a sensitivity analysis to derive the optimal training sample class ratio (β = 1.8) accounting for the unbalanced distribution of land-cover types. We mapped winter wheat planting areas for 1999–2019 with overall accuracies ranging from 82% to 99% and the user’s/producer’s accuracies of winter wheat range between 90% and 99%. We observed an overall increase in winter wheat planting areas of 1.42 × 106 ha in the NCP as compared to the year 2000, with a significant increase in the Shandong and Hebei provinces (p < 0.05). This result contrasts the general discourse suggesting a decline in croplands (e.g., rapid urbanization) and climate change-induced unfavorable cropping conditions in the NCP. This suggests adjustments of the winter wheat planting area over time to satisfy wheat supply in relation to food security. This study highlights the application of Landsat images through GEE in documenting spatio-temporal dynamics of winter wheat planting areas for adequate management of cropping systems and assessing food security in China.

SUMMARYPuddling coarse-textured soils for rice culture in the irrigated tract of the Indo-Gangetic Plains causes high soil strength in the upper layers. This may adversely affect growth and yield of following upland crops. It is possible that no-tillage (NT) in wheat (without residues of preceding rice crop) could aggravate this problem and reduce fertilizer nitrogen (N) use efficiency. In certain production scenarios, NT has been reported to be advantageous because it allows for earlier planting of wheat by eliminating delays caused by tillage. This study examined the combined effects of two crop establishment options for wheat in relation to fertilizer N and planting time following puddled rice cultivation in an irrigated environment of Punjab, northwest India. Combinations of two establishment systems, NT-direct planting and conventional-tillage (CT) with soil disruption to 0.10 m depth in main plots, with two N rates, 120 and 150 kg ha−1 in subplots, were evaluated. Variation in planting time, 31 October (D1) and 7 and 10 November (D2), was used to evaluate effect of planting-earliness. Under D1 in NT, grain yield of wheat was comparable to that under D2 in CT. However, under no advancement of wheat planting in NT, grain yield was 0.2–0.3 t ha−1 less than that in CT. This yield reduction in NT could be overcome by adding 30 kg ha−1 more fertilizer N suggesting that tillage enhanced N use efficiency. These tillage gains are ascribed to the greater extraction of profile stored and applied water and nutrients because of denser crop rooting caused by reduction in soil strength and less weed competition. Higher N use efficiency in CT suggests that farmers could achieve fertilizer N savings with this system. Comparing the tillage systems showed that NT was more cost-effective than CT even after accounting for the cost of additional fertilizer N (saving of Rs. 1685 ha−1) to overcome associated yield penalties under no advancement in planting time.

Research conducted on sowing dates for wheat shows a trend towards increased yield as sowing is advanced (U.K.: Walker, 1980; Bingham et al. 1983; the Netherlands: Darwinkel, Hag & Kuizenga, 1977; Canada: Nass et al.1975; Briggs & Aytenfisu, 1979). In a review of the influence of drilling time on winter wheat in the U.K. McLean (1981) suggested October planting as the optimum. However, sowing before this time often results in increased yield (Bingham et al.1983).

<p>Penelitian tumpangsari gandum/caisim bertujuan untuk mengetahui pengaruh jarak tanam gandum (<em>Triticum aestivum L</em>.) dan waktu penanaman caisim (<em>Brassica rapa L</em>.) terhadap produktivitas gandum dan caisim. Caisim ditanam satu baris diantara dua baris gandum. Sebagai pembanding terhadap hasil, ditanam gandum dan caisim secara tunggal. Percobaan menggunakan rancangan acak kelompok (RAK) faktorial dengan 3 ulangan. Perlakuan meliputi jarak tanam gandum 20cm x 25cm, 25cm x 25cm dan 30cm x 25cm dan waktu tanam caisim 9 minggu setelah tanam gandum (MSTg), 10 MSTg dan 11 MSTg. Penelitian ini dilakukan di lahan penelitian BPTP Sumatera Barat, Arosuka dan Laboratorium Fisiologi Tanaman, Universitas Andalas, Padang. Hasil penelitian menunjukkan jarak tanam gandum dan waktu tanam caisim belum memberikan pengaruh terhadap pertumbuhan dan hasil tanaman gandum dan caisim. Untuk Land Equivalent Rasio (LER) dan Area Time Equivalent Ratio (ATER) menunjukkan sistem tumpangsari gandum/caisim lebih menguntungkan dibandingkan penanaman secara monokultur dengan diperolehnya nilai LER dan ATER &gt;1, sedangkan dari perhitungan Nisbah Kompetisi (NK) tanaman gandum dan caisim diperoleh gandum merupakan komponen dominan dalam sistem tumpangari gandum/caisim.</p><p> </p><p>The research of intercropping wheat/caisim aims to determine the effect of plant spacing of wheat (<em>Triticum aestivum L.</em>) and time planting of caisim (<em>Brassica rapa L.</em>) on the productivity of wheat and caisim. Caisim planted a row between two rows of what. As a comparison of the results and wheat or caisim planted single. Experiment using a randomized block design (RAK) factorial with 3 replications. Treatment includes seed spacing 20cm x 25cm, 25cm x 25cm and 30cm x 25cm and planting time of caisim 9 weeks after planting wheat (MSTg), 10 MSTg and 11 MSTg. The research was conducted in BPTP trials field West Sumatera, Arosuka and Plant Physiology Laboratory, Andalas University in Padang. The result showed seed spacing and time of planting caisim not have any impact on the growth and yield of wheat and caisim. For the Land Equivalent Ratio (LER) and Area Time Equivalent Ratio (ATER) showed wheat cropping system/caisim more profitable than planting in monoculture with LER values obtained and ater &gt; 1, while the Ratio of Competition (NK) wheat crop and wheat gained caisim is the dominant component in the intercropping system wheat/caisim.</p>

Para cada subperíodo de desenvolvimento do trigo são produzidos diferentes órgãos, estando a formação do número destes órgãos dependente da duração de cada subperíodo. A temperatura, o fotoperíodo e a vernalização contribuem significativamente para a determinação da taxa de desenvolvimento da duração desses subperíodos. Neste contexto, este estudo objetivou apresentar um mapeamento da variabilidade temporal dos fatores de ambiente em Pato Branco, e discutir suas possíveis implicações para a expressão do potencial de rendimento de grãos de trigo. Também, buscou-se analisar os períodos do ano que ofereçam as melhores condições de ambiente, em termos de temperatura e radiação solar para a definição do aumento dos componentes de rendimento e desenvolvimento da cultura, buscando as melhores épocas de semeadura para as cultivares em estudo. O experimento foi conduzido durante os anos de 2008 e 2009 na Estação Experimental do Curso de Agronomia da UTFPR, em Pato Branco-PR (26º10’ S; 52º41’W e 750 m). O delineamento utilizado foi de blocos ao acaso, com três repetições no primeiro ano e com quatro repetições no segundo ano, em esquema bifatorial (cultivares BRS 208, BRS 220 e BRS Guamirim x sete épocas de semeaduras). As semeaduras foram efetuadas no período de: 06/05, 17/05, 31/05, 14/06, 28/06, 12/07 e 26/07 para o ano de 2008 e 02/05, 16/05, 02/06, 13/06, 30/06, 13/07, 24/07 para o ano de 2009. Assim, o presente estudo, inicialmente, determinou os diferentes subperíodos de desenvolvimento dos genótipos de trigo testados, assim delimitados: SE-EM, EM-DA, DA-ET, ET-AN, AN-MF. Os estádios de duplo anel e de espigueta terminal foram determinados morfologicamente, em 3 colmos colhidos a cada 48 horas. Para determinação da maturação fisiológica, cinco espiguetas centrais de três espigas, totalizando 15 espiguetas por parcela foram amostradas a cada 72 horas e levadas a estufa, para após serem pesadas, considerando a maturação fisiológica quando apresentavam massa constante. Também, foram avaliadas as implicações do QF no rendimento dos genótipos testados. Foram analisadas as variáveis: altura de planta, massa seca da parte aérea e espigas, índice de colheita e os componentes de rendimento (espigas m-2, espiguetas espiga-1, grãos espiguetas-1 e massa de mil grãos). Conclui-se que não foi possível observar efeito claro, do quociente fototermal (QF) sobre a definição dos componentes de rendimento. Para o ano de 2008 o subperíodo AN-MF, esteve associado com o aumento do rendimento de grãos, somente para a cultivar BRS 220, correlacionando-se posteriormente com o aumento do QF e repercutindo no aumento da massa de grãos. Para o ano de 2009 não foi possível observar correlações do rendimento de grãos com a soma térmica. Entretanto foi verificado entre o QF e a soma térmica do subperíodo AN-MF, para a cultivar BRS Guamirim. Quanto ao rendimento de grãos, esse diferiu entre os anos de alta precipitação (2009) com relação ao ano de baixa precipitação (2008). As semeaduras realizadas nas datas de 30 de maio e 14 de junho ocasionaram os maiores rendimentos de grãos, para os anos de 2008 e 2009, respectivamente.
For each subperiod development of wheat are produced in different organs and is the formation of the number of these organs dependent on the duration of each subperiod. The temperature of the vernalization photoperiod and contribute significantly to determine the rate of development of the length of such sub-periods. In this context, this study aims to map the temporal variability of environmental factors in Pato Branco, and discuss its possible implications for the expression of yield potential of wheat. Also, we attempted to analyze the periods of the year that offer the best environmental conditions, in terms of temperature and solar radiation to define the increase in yield components and development of culture, seeking the best seasons to the cultivars studied. The experiment was conducted during the years 2008 and 2009 at the Experimental Station of Agronomy Course UTFPR in Pato Branco-PR (26º10'S; 52º41'W and 750 m). The experimental design was randomized blocks with three replications in the first year and four replications in the second year in a factorial scheme (BRS 208, BRS 220 and BRS Guamirim x seven sowing dates). The sowings were made in the period of: 06/05 17/05 31/05 14/06 28/06 12/07 and 26/07 for the year 2008 and 02/05 16/05, 02 / 06 13/06 30/06 13/07 24/07 for the year 2009. Thus, this study initially determined the different developmental sub periods of the wheat genotypes tested, so defined: SE-EM, EM-DA, DA-ET, ET-AN, AN-MF. The double ring stages and terminal spikelet were determined morphologically, 3 stalks harvested every 48 hours. To determine the physiological maturity, five central spikelets of three spikes, with 15 spikelets per plot were sampled every 72 hours and brought the oven, for after being weighed, considering the physiological maturity when they had constant weight. Also, we assessed the implications of QF yield of genotypes. The variables analyzed were: plant height, shoot dry weight and ear, harvest index and yield components (spikes m-2, spikelets spike-1, grains spikelet-1 and thousand grain weight). It is not clear effect was observed, photothermal quotient (QF) on the definition of component performance. For the year 2008 the subperiod AN-MF, was associated with increased grain yield, only for BRS 220, correlating with the later increase in QF and reflecting the increase in grain mass. For the year 2009 was not possible to observe correlations of yield with the thermal. However it was observed between the QF and the thermal sub-period of the AN-MF, for BRS Guamirim. The grain yield, this differed between the years of high rainfall (2009) with respect to years of low precipitation (2008). Cultivation procedures conducted on the dates of May 30 and June 14 showed higher grain yields for the years 2008 and 2009, respectively.

CAPES; CNPq
Uma das alternativas para minimizar as perdas de nitrogênio (N), além do uso de cultivares de trigo (Triticum aestivum L.) mais eficientes na utilização desse nutriente, e a identificação de manejos que intensifiquem o aproveitamento do N. Para as cultivares e condições climáticas do Brasil, existem poucos estudos que tenham quantificado como o arranjo espacial de plantas afeta a eficiência de uso do N. O objetivo deste estudo foi avaliar o efeito de diferentes arranjos espaciais (combinação entre densidades de semeadura e espaçamento entre linhas) no desempenho agronômico e aproveitamento do N mineral aplicado. O experimento foi conduzido em Pato Branco, nas safras agrícolas de 2014 e 2015, em delineamento em blocos ao acaso, em modelo fatorial, com três repetições. Dois cultivares de trigo (CD 150 e Ametista) foram submetidos a quatro densidades de semeadura (150, 300, 450 e 600 sementes m-2), duas doses de N (20 e 120 Kg ha-1) e dois espaçamentos entrelinhas (0,17 e 0,25 m). As maiores produtividades de grãos foram alcançadas no menor espaçamento entrelinhas e alta dose de N, para ambos os cultivares e anos avaliados. As densidades, para máxima eficiência técnica, de 400 sementes m-2 para a cultivar CD 150 e 425 sementes m-2 para a cultivar Ametista proporciona os maiores rendimento de grãos, ambas para o menor espaçamento. A eficiência de uso, de absorção e de utilização do N foram superiores nas condições com menor nível de N. Em ambos os espaçamentos utilizados, a eficiência de uso do N foi favorecida no menor espaçamento, bem como a eficiência de absorção do N. Os resultados permitem concluir que o teor de N proveniente da mineralização da matéria orgânica deve ser empregado como parâmetro para aplicação de N em cobertura. Com isso, evitar o uso excessivo do mesmo e otimizar tanto o rendimento de grãos quanto os parâmetros da eficiência de uso do N.
An alternative to minimize Nitrogen (N) losses, beyond use of more efficient wheat (Triticum aestivum L.) varieties on the use of this nutrient, is the identification of managements to intensify the use of N. For the varieties and climatic conditions of Brazil, there are few studies that have quantified how the spatial arrangement of plants affects the N-use efficiency. The objective of this study was to evaluate the effect of different spatial arrangements (combination between seeding rates and row spacing) on agronomic performance and utilization of the applied mineral nitrogen. The experiment was conducted in Pato Branco in the crops year 2014 and 2015, in a randomized block design, a factorial model, with three replications. Two wheat cultivars (CD 150 and Ametista) were submitted to four seeding densities (150, 300, 450 and 600 seeds m-2), two N doses (20 to 120 kg ha-1) and two row spacings (0.17 and 0.25 m). The highest grain yields were reached at the lowest line spacing and high nitrogen dose for cultivars and evaluated years. The densities, for maximum technical efficiency, of 400 seeds m-2 for the cultivar CD 150 and 425 seeds m-2 for the cultivar Ametista provides highest grain yield, for both cultivars and years evaluated. The N-use efficiency, N-uptake efficiency and N-utilization efficiency were higher in the conditions with lower level of N. In both spacings used, N-use efficiency was favored in the least spacing, as well as N-uptake efficiency. The results showed that the N content from the mineralization of organic matter should be used as a parameter for N application in the cover. Thus, avoiding excessive use of it and optimize both the grain yield as the N-use efficiency parameters.

Millions of hectares of temperate woodland and billions of trees have been cleared from Australia’s agricultural landscapes. This has allowed land to be developed for cropping and grazing livestock but has also had significant environmental impacts, including erosion, salinity and loss of native plant and animal species. Restoring Farm Woodlands for Wildlife focuses on why restoration is important and describes best practice approaches to restore farm woodlands for birds, mammals and reptiles. Based on 19 years of long-term research in temperate agricultural south-eastern Australia, this book addresses practical questions such as what, where and how much to plant, ways to manage plantings and how plantings change over time. It will be a key reference for farmers, natural resource management professionals and policy-makers concerned with revegetation and conservation.

After years of ancestral journeys of the human psyche and the development of four transcendental research macroprojects in the field, it is time to undertake the method of ancestral walking on the living system of mother earth and her human son as a verifiable sense of essential nature and substantial of the soul. Method of walking in the loving order of the ancestors, the father and the mother, the cosmos and the earth, the sun and the moon. Co-responsible planting of bridging the integration of the ancestral left hand and the western right hand from the sensible, the construction of mythical thought as great logos, Huitaqa (thought) of the path of the soul (Sunna Gua), of the theory on the radical cosmogonic bases and epistemological of the spiritual foundation and of the individually and collectively mythical, mystical, botanical and ritualistic therapeuticsof the human psyche. Saved the modernist shames, a writing is presented on the proper as philosophy, science and psychology, for this reason, the scope of the present emergence of the quantum in the sacred fabric of a founding myth that recognizes and honors in psychism the evolutionary force of human conscience, an ancestral bet of increases of conscience in the confidence for the power of this soul that is sown fertile for the healing, transformation and evolution towards to the great spirit. What can a reader find in your narrative? Perhaps a sense of the lost and absent not clarified, the great illness of the contemporary psyche, the lack of faith, the absolute loss of confidence in the mythical and sacred presuppositions of the traditions that build culture, for the same reason the urgency of recovery from a stark bridging of law of origin to an ancestral psychology that consolidates such a human pretense of life in the life of the planet.

The chapter shows how, within a year after the Discalced Carmelites of Teresa of Avila’s reform were founded in France, opinions diverged on just what constituted an authentic Teresian reform. Spanish nuns brought to guarantee the new order’s authenticity found Paris’s convent of the Incarnation too big, too grand, and too ambitious to lead the order’s expansion. They worked to ensure that the second convent, founded outside Paris at Pontoise, conformed more closely to Teresa’s desire to keep the houses small and poor. The chapter uses written records and art to show how nuns at Pontoise created their own vision of an authentic Teresian convent but in doing so provoked a rivalry that threatened at times to divide the rapidly growing French order. The case illustrates well the challenges not just of defining and enacting religious reform but also of adapting reform to local circumstances and values.

This chapter examines the pre-existing definitions of what corruption entails starting from the abuse of public office for private authority to forms of political and divisional advantage. Definitions of police corruption follow to analyse a variety of activities that qualify as police malfeasance related to famously cited criminological literature concerning typologies. The typologies list the activities that range from corruption of authority, kickbacks and finally planting of evidence (that includes drugs). Integrity violations are then examined to cover a broader range of police malpractices such as moonlighting and criminal activity in private time. Moreover, the debate of bending rules which includes the use of the ‘magic pencil’, perjury or excessive means of coercion for a noble and/or justified outcome as part of departmental advantage is reached.

Spring always seemed to begin for us with spring break, when we had a whole week to be at the Shack and do the planting together. Spring is such a special time, with the buds bursting and the early flowers opening. Ever since we started planting in the spring of 1936, we always looked forward to the project, though it meant a fair amount of work, and we always had such a marvelous time. The preparations each year were considerable. Mother and Dad would sit at the dining room table in Madison with a list and plan what kind of meals we might like to have up there and what supplies would be needed. Dad would order in advance thousands of pines from the Conservation District. He ordered at least two-year-old seedlings, usually at least two thousand white pines and two thousand reds for a season, and sometimes more. As soon as we arrived at the Shack we would prepare the slurry of red clay and water (as described earlier), dip the roots of each bundle of pines in the clay to protect them, and dig a short ditch “to spud them in” (as Dad called it). The ditch was in the shade west of the Shack so the pines seedlings would not dry out. During the drive up our car was usually jam-packed with gear, and Gus or Flicky the dog. To keep things organized, we used the old chuck boxes Dad had used to lash to his packhorse when he worked in New Mexico. We generally stopped in Baraboo for a twenty-five-pound block of ice so we could keep our vittles cool. If Starker joined us he brought his little roadster to help carry the gear. We also looked forward to the guests sometimes invited to help us plant. Daddy’s sister, Marie Leopold Lord of Burlington, Iowa, fit right in. She was lots of fun, and a great botanist with a special interest in ferns. One year our visitor was a forester Dad had met in Germany, Adelbert Ebner, who was a jolly fellow perhaps fifty years of age, and quite a musician.

An enduring problem of social life is what to do about the future. Can we predict it? Can we control it? How much sacrifice are we willing to make in the present for the promise of a better future? The questions are harrowing, and agreement comes hard. The year 1921 was a time of famine in some parts of the newly formed Soviet Union. An American journalist, visiting a refugee camp on the Volga, reported that almost half of the people had died of starvation. Noticing some sacks of grain stacked on an adjacent field, he asked the patriarch of the refugee community why the people did not simply overpower the lone soldier guarding the grain and help themselves. The patriarch impatiently explained that the seed was being saved for next season's planting. "We do not steal from the future," he said. It would be too much to claim that only the human animal is capable of imagining what is yet to come, but it is difficult to believe that any other animal can have so keen an appreciation of the demands of the future. Alfred Korbzybski (1879- 1950) called man "the time-binding animal." Binding the future to the present makes sense only if understandable mechanisms connect the two. This understanding was notably missing in the writings of the anarchist-journalist William Godwin. Unlike Malthus, he could make no sense of the fluctuations of human numbers. "Population," he said, "if we consider it historically, appears to be a fitful principle, operating intermittedly and by starts. This is the great mystery of the subject.. .. One of the first ideas that will occur to a reflecting mind is, that the cause of these irregularities cannot be of itself of regular and uniform operation. It cannot be [as Malthus says] 'the numbers of mankind at all times pressing hard against the limits of the means of subsistence.'" Rather than trying to see how appearances might be reconciled with natural laws, Godwin simply said there were no natural laws. His proposal to replace law with "fhfulness" led one of his critics to comment: "Perhaps Godwin was simply carrying his dislike of law one step farther. Having applied it to politics (1793) and to style (1797), he now applied it to nature (1820). He deliberately placed a whole army of facts out of the range of science."

Many of us who work with pencil, pen, or computer like to vary the intellectual routine by doing something “real.” Some build cabinets and canoes, some sing in choral groups, others join first aid squads. I take care of our garden. Gardening is an especially good activity for eggheads because it combines physical labor with the opportunity to be creative. Unlike the ideas in the books I write, however, my creations in the gar-den are quickly put to the test. My experience last summer is a case in point. I like to eat what I grow, so I have little patience with flowers and other ornamentals. I tolerate the ones that were planted around the house when we first arrived: yew, hemlock, cherry laurel, forsythia, flame azalea—the usual things provided by botanically challenged, cost-conscious builders. If these woody perennials get sick I do what I can for them, given my lack of knowledge and low level of interest. Some times I fertilize, sometimes I continue to refrain from fertilizing, depending on my intuition in the particular case. The same goes for watering. Our flame azalea is down to one tiny branch with eleven leaves on it, about the same as last year. I don’t know whether I am keeping it alive against all odds, or preventing it from making the full recovery that it would be capable of if cared for by somebody else. I view my role in the treatment of our ornamental plantings like that of the remote HMO clerk who makes the critical decisions in a complex medical case; any unfortunate consequences of my ignorance are not of great concern. Fruits and vegetables are another matter. I am not much more knowledgeable about them than about azaleas, but I try a lot harder. Because this is a story about vegetables, I will skip the fruits, except to note that we pick our own sour cherries, figs, peaches, plums, grapes, apricots, and apples—in sharply decreasing order of abundance (squirrels got all of my apples this year).

The Nile slashes through the eastern Sahara Desert like an arrow, a stalk of green amid some of the most arid landscape on earth. Each summer, floodwaters from deep in tropical Africa inundate the floodplain, depositing fertile silt and nourishing growing crops, enabling an Egyptian civilization to endure for five thousand years. Along the river’s banks, pharaohs, considered to be living gods, created a palimpsest of pyramids, rock-cut tombs, and temples that have fascinated the traveler since Herodotus’s day. Egypt was the land of Ra, the sun god, whose golden rays shone day after day in an unchanging chronicle of human existence and immortality— birth, life, and death. Ra’s rays shine between the serried pillars of Karnak’s Hypostyle Hall, darken the jagged contours of the Valley of Kings in deep shadow, project the steep slopes of the pyramids of Giza over the surrounding desert. Ancient Egyptian ruins cast a profound spell over the visitor, especially in the days before Egyptologists measured the ruins and recorded their secrets. They were desolate, unfamiliar, their gods irrevocably gone, the hieroglyphs on the walls unintelligible except to a privileged few—and that only after about 1830, when Jean François Champollion’s decipherment came into common use. But the sense of time and history these monuments conveyed was, and still is, pervasive. The figures on temple and tomb walls expose the habits, fantasies, and beliefs of thirty dynasties. Even today, there is an underlying sense of permanence along the Nile. The pharaohs have vanished, succeeded by caliphs, pashas, colonial overlords, and presidents, but life along the Nile still follows a timeless routine of planting and harvest, of life and death. The traveler has been part of this timeless landscape for more than two thousand years. We have already encountered Roman tourists at the Colossi of Memnon. Christian pilgrims on their way to Jerusalem passed through, too, although travel was difficult for the faithful in what was now Islamic territory. The founding in London of the Levant Company in 1581, originally to foster trade with Turkey—among other things, trade in coffee—brought more visitors, some of them in search of mumiya, pounded-up Egyptian mummy, considered to be a powerful aphrodisiac.