THE FOREST NURSERY 253 



of, however, considerable quantities of mild manure, such as leaf 

 mold, can be used to advantage in the seedbeds. 



Provision for manures of vegetable origin must be made at 

 least 1 year and usually 2 years in advance, because of the time 

 required after gathering and bringing to the nursery before they 

 are sufficiently disintegrated for advantageous use. Better results 

 can usually be obtained at equal cost on average soils by adding 

 animal or mineral fertilizers to those of vegetable origin because 

 of their greater richness in available plant nutrients and the much 

 less quantity required. 



26. SOILING PLANTS IN NURSERY PRACTICE. A great variety 

 of soiling plants are used in nursery practice. Leguminous crops, 

 such as cowpeas, field peas, soy beans, and lupines are usually best 

 for this purpose because of their importance in increasing the 

 supply of nitrogen. Buckwheat and rye are often useful on sites 

 where nitrogen is supplied in other forms, because of the large 

 amount of organic matter produced in a comparatively short 

 time and the volume of humus that results from their decay. 

 Cowpeas have given excellent results and are used by many nur- 

 serymen in the United States. The peas are sown broadcast in 

 late May or early June, following the removal of the transplants. 

 The crop is rolled to the ground in the autumn before the first 

 severe frost and while the seed is still green. It is then covered 

 with a heavy dressing of well-rotted farm manure, at the rate of 

 10 to 50 tons per acre. 



Good results have been attained on light, sandy soils by ap- 

 plying a heavy dressing of stable manure in the winter or early 

 spring and growing a soiling crop the following summer. This 

 crop is plowed under in the autumn and the seedbeds or trans- 

 plant beds prepared the following spring. The soiling crop not 

 only enriches the soil in nitrogen but, when grown on a heavy 

 dressing of stable manure, breaks it down into more usable form 

 for the following crop. 



Buckwheat is very largely used in the forest nurseries in New 

 England. It grows well on a variety of soils, can be sown as late 

 as June, and plowed under 2 or 3 months later. There is no 

 better crop for clearing the soil of weeds, and none that rots 

 more rapidly after plowing under or that leaves the soil in better 

 physical condition for nursery crops. Excellent results have been 

 attained on the sandy loam soils near New Haven, Conn., by 



