Orchard Culture — General Slaicments. 33 



the second or third year after planting, and have yellowish 

 foliage, while being apparently free from parasites, we may 

 conclude that their growth is being restricted by a lack of 

 plant food, or of moisture, or both. The physical condition 

 of the soil should be first considered. If the soil is hard 

 and lumpy, humus should be added bj' growing some of 

 the coarser cover crops, as rye or cow peas, or farm manure 

 may be plowed in early in the spring. This treatment will 

 probably produce the desired growth. If, as the trees reach 

 bearing age, the}' are making very rapid growth and show 

 little inclination to fruit, it may be inferred that they are 

 receiving too much nitrogen. Non-nitrogen-gathering 

 cover crops should then be used, and the proper balance 

 restored by adding phosphoric acid and potash. Unleached 

 wood ashes at the rate of 30 to 50 bushels per acre are ex- 

 cellent for furnishing these constituents. Leached ashes 

 are well worth applying, since they contain nearly all of 

 their original phosphoric acid. In the absence of ashes, 

 jihosphoric acid and potash may be purchased in various 

 forms. The first may be had as high-grade plain super- 

 phosphate or in bone meal. The former contains 16 to 18 

 per cent, of phosphoric acid, and 200 to 500 pounds per 

 acre is a good dressing for a bearing orchard. Bone meal 

 contains about 24 per cent, of total phosphoric acid, and 

 about 3 per cent, of nitrogen. Two hundred to 500 pounds 

 per acre is sufficient for oue application. 



Potash is generall}' considered the most important con- 

 stituent in orchard fertilizers, since fruits withdraw larger 

 quantities of this component than of nitrogen or phos- 

 phoric acid. Nitrogen, while relatively more expensive 

 than potash, may be provided by growing leguminous 

 cover crops. Muriate is perhaps the best form in which 

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