184 FARM CROPS 



cutaway or spring-tooth and smoothing harrow. 

 In lieu of clover sod, any land answering the above 

 requirements that is in good tilth will give fairly 

 satisfactory results. Thorough preparation should 

 be the keynote of any soil. 



Fertilization Necessary. If the land is thought 

 to be lacking in both humus and plant food, these 

 deficiencies can be supplied by a good application 

 of barnyard manure. This should be spread on the 

 land after plowing in the fall and thoroughly in- 

 corporated with it in the spring fitting. An appli- 

 cation of stable manure in the spring is not desir- 

 able, as this practice tends to produce scabby 

 tubers. If well-rotted manure is available it may 

 be used. Usually on all soils well supplied with 

 humus, commercial fertilizers will serve the pur- 

 pose much better than barnyard manures, as they 

 may be applied in definite proportions to suit the 

 needs of the plants. 



Early potatoes require more liberal application 

 of quick-acting fertilizers than do late ones. An 

 application of 1,000 pounds of a commercial fer- 

 tilizer containing nitrogen 5 per cent, phosphoric 

 acid 8 per cent and potash 10 per cent, has been 

 found to give good satisfaction with early potatoes 

 on light soils. Much larger amounts than these 

 are frequently used by truck growers near large 

 cities. For late potatoes a less active fertilizer 

 is needed, as the plants have more time in which 

 to develop. In this case an application of 800 to 

 1,000 pounds commercial fertilizer containing nitro- 

 gen 2 to 3 per cent, phosphoric acid 6 to 8 per cent, 

 and potash 8 to 10 per cent is considered sufficient. 

 Each grower, however, must determine, in a large 

 measure, the requirements of his own soil. Com- 



