MONTANA 



1365 



The food elements removed by bearing 

 apple trees during a period of 20 years 

 have been estimated to be: 



Phosphoric 



Nitrogen Acid Potash 



Apples 498.6 38.25 728.55 



Leaves 456.75 126. 441. 



Trees 283.15 107.47 264.25 



Total pounds.. 1,238.5 271.7 1,433.8 



If trees were able to remove all the 

 plant food elements from the soil (which 

 they are not) there would be enough ni- 

 trogen, in the soil analyzed, to last a fruit 

 crop 30 years; enough phosphoric acid to 

 last 150 years and enough potash to last 

 about 160 years. The above analysis was 

 from the top eight inches of soil, and 

 since fruit trees gather food to a much 

 greater depth, it is evident that there 

 would be much more of the plant food 

 elements per acre than is indicated above. 

 However, plants cannot take all the ele- 

 ments from the soil for many reasons, 

 chief among which is the fact that a large 

 portion of the elements in a soil are una- 

 vailable for plant use until made so by 

 proper tillage, application of humus and 

 other means. 



On the sage-brush benches of the east 

 side there is but little humus in the soil, 

 and through continuous clean cultivation 

 what humus there is is soon worn out 

 and the soils become hard and compact 



and a poor place to grow profitable crops 

 of fruit. 



Within the past few years much 

 thought and study has been given to the 

 subject of getting humus into the soil 

 in order that the plant foods therein may 

 be made available, to loosen the soil and 

 put it into condition to take up and re- 

 tain moisture, and to make it possible for 

 the soil bacteria to work, which is very 

 essential to the best growth of plants. 



The application of barnyard manure 

 would accomplish these things, but in the 

 large acreage planted to trees this is im- 

 possible to do. Field peas, clover, alfalfa 

 and other legumes are now being planted 

 and plowed under as green manures with 

 very beneficial results. 



Field peas are planted in the spring as 

 early as germination can take place, and 

 are usually in condition to plow under 

 by July 15. The clovers are planted in 

 the spring with some nurse crop and are 

 grown until the summer or fall of the sec- 

 ond year. When clover is planted among 

 young trees there is an appreciable check 

 to the growth of trees during the time 

 the clover is growing, and the soil needs 

 much more water than when in clean cul- 

 tivation. After the clover is plowed un- 

 der the trees take on a new growth and 

 will soon look as vigorous and thrifty as 



-M 



Young Apple Orchard in the Bitter Root Showing Clean Cultivation. 



