资源 标记: Vita
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- 1986-01-01 Most animal science manuals have focused on the care and management of common breeds of domestic animals to achieve greater production. This manual emphasizes the environmental factors that affect livestock and livestock interactions. Standard livestock texts should be consulted for detailed...
- 1989-01-01 This paper will describe the basic features of a medium- to large-scale hydroponics system and prefabricated greenhouse appropriate for cold climates. Some modifications for a system suitable for hot climates are also discussed. Home gardeners in any climate can use the basic theories contained...
- 1985-01-01 Insect control is the effort made to protect crops, animals, or other targets of insect attack from unacceptable injury or loss. If destructive insect populations are allowed to cause significant damage or injury to their target host, economic loss or a decline in human health may result....
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- 1990-01-01 Because chickens and ducks can utilize surplus grain, table scraps, garden trimmings, and by-products, they can provide a valuable food reserve. Some farming communities produce more grain than their people need. Of course the excess could be sold, but if not, it can be fed to poultry. Then, if...
- 1985-01-01 Every farmer and gardener realizes that plants receive some of their substance from the soil. Just how much plants depend on soil fertility is not always obvious, however, because so many other factors also influence plant growth--water, sunlight, pests, and plant variety (genetics). In regions...
- 1981-01-01 This bulletin contains easy-to-follow, well-illustrated directions for making fertilizer with materials likely to be found in a village situation. Included are instructions for making the fertilizer in a simple frame or container, a list of possible raw materials, and a list of general...
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