ix.] CONDITION 275 



Condition. 



The question of condition has equally its chemical 

 and its mechanical side ; it is well known that on 

 any but the lightest soils continued cultivation makes 

 the texture better and renders it easier to obtain a 

 seed bed. On clay soils the effects of bad manage- 

 ment are very persistent ; any ploughing, rolling, or 

 trampling when the soil is wet will so temper the 

 clay that the effect is palpable until the land has been 

 fallowed again or even laid down to grass. Once 

 protected from the action of frost, stiff soil which has 

 been worked when at all wet never seems able to 

 recover its texture, as may be seen by examining the 

 clods that are to be found on digging up an old post, 

 the result of the trampling when the post was originally 

 put in. The dependence of " condition " upon the 

 maintenance of a good texture is to be seen in the 

 custom of regarding wheat as an exhausting crop, 

 whereas few of our farm crops withdraw less plant 

 food from the soil. The popular opinion really 

 represents the fact that the wheat crop occupies the 

 land for nearly a year, during which period it receives 

 little or no cultivation, and so falls into a poor state of 

 tilth. 



From the chemical side " condition " means the 

 accumulation within the soil of compounds that will 

 by normal decay yield sufficient available plant food 

 for the requirements of an ordinary crop, e.g., of 

 organic compounds of nitrogen which readily nitrify, 

 of phosphoric acid and potash compounds which readily 

 become " available " for the plant. A soil in good con- 

 dition must also contain an abundant flora of the 

 ammonia-making and nitrifying bacteria ; indeed high 

 condition is almost measurable by the content of the 



