NURSERY PRACTICE FOR PRAIRIE -PLAINS PLANTING 53 



Thus it will be seen that 50 tons per acre of an animal manure 

 having 1.0 percent nitrogen, 0.3 percent phosphoric acid, and 1.0 

 percent potash would add 1,000 pounds of nitrogen, 300 pounds of 

 phosphoric acid, and 1,000 pounds of potash, and if plowed into the 

 top 7 inches of soil would theoretically increase the total nitrogen 0.05 

 percent, total phosphorus 0.015 percent, and total potash 0.05 percent. 

 The generally low phosphoric acid content of most animal manures 

 suggests the necessity of supplementing them with the superphos- 

 phates, especially in plains nurseries. 



Since animal manures, especially the wet manures, lose a high 

 percentage of their value through leaching or too rapid fermentation, 

 they should be put into a concrete or puddled-clay pit. If any 

 considerable rainfall is expected, there should be a tight roof over the 

 pit, or at least a layer of soil 1 foot thick. To keep loss to a minimum, 

 the material should be kept compact and moderately moist. These 

 precautions will retard denitiification. The tight pit will prevent loss 

 of the soluble portions, particularly nitrogen and potash, of which half 

 or more exists in soluble form in farm manure. 



The rotted manure, and also the liquid portion, can be applied to the 

 nursery in late fall after the stock has been dug, and it is considered 

 good practice in arid or semiarid regions to plow under the manures 

 to aid in their decomposition rather than to let them lie on the dry 

 surface. Such applications can be made every other year in treat- 

 ments of 10 to 30 tons per acre, depending on the soil, species of trees 

 grown, and other factors. 



SOILING CROPS AND OTHER FERTILIZERS 



It may be found necessary, in addition to the use of farm manure, 

 to sow a soiling crop every third or fourth year. This crop can be 

 either a legume or a grain and should be plowed under while it is still 

 succulent and immature. Mature soiling crops do not decompose 

 rapidly and may produce a seed crop that will germinate the following 

 year and add to weeding costs. One of the best ways of using animal 

 manures most effectively is applying them to the soil before sowing 

 the soiling crop. On the other hand, a good soiling crop cannot be 

 produced if soil fertility is low, and this makes an application of some 

 fertilizer before sowing, especially animal manure, most advisable. 



For nursery work, preference should be given to legumes such as 

 cowpeas, soybeans, vetch, and field peas, which are sown in spring and 

 turned under in summer. Grain crops such as rye or oats also are 

 excellent. The rye is often sown in fall, turned under in early sum- 

 mer, and followed by a crop of legumes. 



From a nursery production angle, sweetclover and alfalfa have a 

 disadvantage in that they are deep-rooted, persistent, and hard to kill. 

 The latter does not produce much growth in 1 year, although from the 

 point of soil building, both crops are rated very high. 



If a very heavy crop is produced, it can be disked before plowing to 

 aid in getting it turned under more completely. The plowing should 

 be done at least 4 to 6 weeks before nursery sowing in order that the 



