STRAW, STEMS, ETC. 271 



first crop will be less obvious, but its influence will continue longer. 

 There are manures which act, it may be said, at the moment they 

 are put into the ground ; there are others, the action of which con- 

 tinues duvincT several years. Nevertheless two manures, although 

 actincT within periods so different in point of extent, will produce 

 the same final result if they severally contain the same dose ot 

 azotic elements, if they are of the same intrinsic value. 



The durability of manures, the length :f time during which they 

 will continue to" exert thJr influence, is a matter of great impor- 

 tance. It often depends on their state of cohesion, or on their in- 

 solubility, though climate and the nature of the soil have also a 

 marked influence on their decomposition and consequent effects. It 

 ■is not easy in the present state of knowledge to predict with cer- 

 tainty how long the beneficial effects of a given manure will con- 

 tinue to be felt ; but we know well enough what will hasten the 

 decomposition of manure, and what will retard this final result, and 

 so apportion as it were the fertilizing principles among the different 

 crops in the rotation. Aware of the importance of azote in manures, 

 M. Payen and I undertook an extensive series of analyses, with a 

 view to ascertain the proportion of this principle in the various mat- 

 ters and mixtures made use of in the improvement of the soil. This 

 labor enabled us to class manures ; and assuming farm-dung as the 

 standard, to refer each to its place in a comparative scale, I shall 

 give the conclusions to which we came in the tabular form ; but be- 

 fore doing this, I think it necessary to premise a few observations . 

 upon the°several manures, or substances usually employed in prepar- 

 ing manures. j rru e 



Straw, looody stems, haum, leaves, and zveeds. I he straw ot 

 corn, the haum and stalks of various plants of farm growth, weeds of 

 all kinds, and leaves collected in the woods, all contribute to in- 

 crease the supply of manure. • , 1 



Straw is the article that is generally employed for litter ; its hol- 

 low tubular structure, which makes it apt to imbibe urine, renders it 

 peculiarly valuable for this purpose ; and it at the same time sup- 

 plies a soft and warm bed for the cattle. The weight of the straw 

 used as litter may be doubled by the absorption of urine and admix- 

 ture with excrements ; but it is by its very nature and of itself a 

 manure which is not to be slighted, since it contains from 2 to 6 

 thousandths of azote. 



The stems of leguminous plants— bean and pea straw— are much 

 more highly azotized than the straw of corn ; it is certainly best to 

 consume this article as forage when it is not too woody and hard. 

 As litter it is often unfit to form a good bed for cattle, and should 

 therefore not be so employed alone ; but it presents the twofold ad- 

 vantage of adding to the manure a large proportion of azotized prin- 

 ciples'^ and at the same time of effecting a saving of straw. At 

 Bechelbronn we have found it very advantageous to mix a certain 

 quantity of the dried stems of the Madia saliva (gold of pleasure) 

 "with both our cowhouse and stable litter. 



In forest districts, the leaves of trees are frequently used as lit- 



