ROTATION OF CROPS. 215 



I believe it more probable that the farmer will find it more profitable to use that amount of 

 manure which shall enable him to raise that kind of grain, or stock, or pursue that course of 

 husbandry which his location and position will dictate. 



But a succession of crops is not an indifferent matter. Wheat will not succeed well in a 

 highly manured field, while maize, or Indian corn, can scarcely be manured too highly. In 

 seeding down a field it is not a matter of indifference what crop is to succeed : oats may be 

 selected as the crop to succeed a grass and clover crop ; a hoed crop, as potatoes, is good pre- 

 paration for wheat, if the tillage has been thorough. But a short course, like the following, is 

 more generally adapted to the soils of New- York than any other : 1. manure : 2. Indian corn : 

 3. oats and clover, and ending the rotation with wheat. But wheat may succeed Indian corn, 

 then clover, and wheat again. In this country it is rare to make a potato crop a part of a ro- 

 tation ; and turnips have not been cultivated to that extent here which they have in England 

 and upon the continent. This arises mainly from the estimation of maize ; though it may be 

 regarded as an expensive crop, still its value warrants the expense. It will be seen, by refe- 

 rence to the analyses in the second volume, that wheat, if its straw is regarded, is a silica plant ; 

 and in some varieties potash is also a prominent element, while the phosphates are reduced to 

 a small quantity ; sulphuric acid is also quite prominent. The composition of the chaff does 

 not differ essentially from the straw, though the phosphates are often reduced to a minimum, 

 and the silica increased to its maximum quantity. When, however, we examine the composi- 

 tion of the grain, it must be ranked as a phosphoric acid plant, as the phophates constitute 

 more than one half of the elements of the grain. Potash is prominent among the elements : 

 soda is often a variable element. In the grain sulphuric acid is not so prominent as in the 

 straw. Beans are as rich in phosphates as wheat, and more so than barley. Barley requires, 

 apparently, the organic salts of lime ; the straw of barley is not so siliceous as wheat, and 

 that of oats is less than either ; in fact oat straw may be regarded as a tolerable fodder for cat- 

 tle, especially if cut early : sulphuric acid is found in each. In wheat, chlorine is a scarce 

 substance ; and hence it would appear that the practice of some farmers, of employing salt as 

 a manure, is of little utility. The ash of potatoes is more than half potash, but the ash is a 

 small percentage ; still when it is considered that a potato crop is large, it will satisfy us that 

 the amount of expensive material removed is very great. The same is true with the turnip, 

 but the potash is less in amount. The common hay crop, being one in which lime (probably 

 the organic salts of lime) abounds, may follow or succeed a crop in which potash, or the phos- 

 phates are prominent substances. Timothy, red-top, and clover furnish considerable carbonate 

 of lime in their ash. 



The expensive elements of the soil which are liable to exhaustion, are phosphoric acid, 

 potash, soda, lime and organic or nitrogenized matter. A rotation, where fear of exhaustion 

 guides the farmer, will have reference to these bodies. Silex, iron and alumina, are each 

 abundant in most soils ; silex at least, is never wanting, though it may not exist in a soluble 

 condition ; alumina is present in all soils, except those which are very siliceous ; it is not 

 taken up by plants, and hence is not to be regarded as an aliment, but is required in the soil to. 



