Manures and Fertilizers 127 



is essential to prevent root injury. Application with the 

 planter works w-ell whenever moisture is abundant in 

 the soil throughout the growing season in Maine. As the 

 amount applied to the acre increased to 1000 pounds or 

 more, growers began to use a wider distribution through 

 the soil. With such large amounts, there is no need of 

 specially placing some of it near the plants, as a fraction 

 is enough to act as a starter. 



At the present time heax-A' applications of fertilizer are 

 used in the specialized potato-growing districts in this 

 country, with the idea of supplying so much that the grow- 

 ing plant will never suffer for lack of plant-food at any 

 time. For such amounts as 1000 to 3000 pounds to the 

 acre, broadcasting is coming into use in whole or in part. 

 Ordinary grain-drills or special broadcast fertilizer sowers 

 are used. All fertilizers broadcasted should be thoroughly 

 worked into the soil. While there is some tendency for 

 soluble fertilizer salts to work downward into the soil, 

 there is likely to come any summer, after potatoes are 

 planted, a hot and dry time when several inches of the top 

 soil is very dry. The fertilizer in such a dry soil is prac- 

 tically useless to the crop for lack of sufficient water to dis- 

 solve it. This is especially true when a surface mulch of 

 dry soil is maintained for the purpose of conserving the 

 moisture in the earth below. This accounts for some of the 

 contradictory results obtained by experimenters on com- 

 parisons of the application of fertilizers by the drill and 

 broadcast methods. Under the conditions of northern 

 Maine, in which the water in the soil is usually abundant, 

 part of the hea\y fertilizer used is often put on after the 

 plants are up, being applied to the ridge and covered with 

 soil. It is doubtful whether this method would be a 

 success in other regions, even in some other parts of 



