No. 6. DEPARTMENT OF AGRICULTURE. 443 



quantity of it, aud at the same time leave the soil and the fertility in 

 better condition for weaker feeding crops. Corn is not injured by 

 the excessive application of fertilizer like wheat, barley and oats 

 would be. Buckwheat has strong feeding powers, and will usually 

 thrive under favorable climatic conditions where few other crops will 

 grow, and is not infrequently used as a manurial crop, by plowing 

 down after it has extracted and rendered available soil fertility for 

 weaker feeders. The surface feeding habits of i)otatoes and their 

 limited power of obtaining potash and lime causes a more rapid 

 decrease in yield per acre than any other farm crop, if planted succes- 

 sively on the same soil. 



Leguminous crops have a special weakness in getting potash and 

 lime, and, therefore, should be placed in such a position in a rotation 

 where these fertilizers can be applied directly or where they are 

 most available, if already in the soil. Legumes even with the ap- 

 plication of potash and lime, W'hen grow'u too frequently on the 

 same soil, will often fail because of the production of organic sub- 

 stances which destroy them. Hay and grass crops mostly have 

 shorter roots than the cereal grains, aud are, therefore, by habit sur- 

 face feeders, and can not obtain mineral foods at any depth; there- 

 fore, in order to raise hay crops the fertilizer should be applied 

 directly on the surface, so that it is within easy reach of the roots 

 of the plants. No manure is better adapted for raising grasses than 

 common farm manure. 



These plants then have the power to break up molecular struc- 

 tures in the soil which otherw^ise can only be broken by the most 

 powerful chemical agents or which will only yield their hold on each 

 other by the decomposing agency of temperatures measured by 

 hundreds of degrees or by the immeasurable heat of the electrical 

 furnace. They have the pow-er to obtain water from the soil, and 

 must obtain it under these conditions; when that soil is so dry that 

 no pressure on the earth beneath could express from it a drop of 

 water, and at such a rate too that an acre of corn under ordinary 

 conditions will have suflScient to consume 244 tons in 13 days. We 

 see here the importance of water to the growing plant, not only for 

 circulation and transportation, but to help it in forming the sub- 

 stances by means of which it will be enabled to render available the 

 plant food it needs. Not only must the soil contain a large quantity 

 of water, but it must be well aerated, for oxygen is just as necessary 

 as any of the plant foods, because, as we well know, that when 

 a soil is super-saturated with water, or when it is baked so hard that 

 no air can get in, plants will die, not for want of plant food or 

 water, but for want of air or oxygen. Furthermore, we should con- 

 sider the adaptability of the soil to the crops that we cultivate, so 

 that soils and crops would work together to produce the best results. 



