256 Bulletin 254. 



these may be broken off. Such effects are most noticeable on tap-rooted 

 plants, such as the clovers, but it is almost as injurious to the grass and 

 grain crops. Nor is the injury of heaving confined to small plants. It 

 extends to trees and even to fence posts, the latter being lifted out of the 

 soil by successive freezes. This effect of drainage in reducing or prevent- , 

 ing " heaving '' is very generally known by men of experience in the prac- 

 tice. Speaking of the effect in 1851, Mr. Johnston said, "Heretofore 

 many acres of wheat were lost on the upland by freezing out, and none 

 could grow on the low lands. Now there is no loss from that cause." 

 Mr. Sanford Howard of the Boston Cultivator, in writing in 1852 of the 

 effects of drainage on Mr. Johnston's farm, says. " This year when much 

 complaint is made of wheat 'freezing out' and of the weevil or white 

 midge having greatly injured it his crop will, according to the best judges, 

 average over thirty bushels per acre. There was no freezing out here; 

 every grain vegetated and every plant bore its proper quota. The fields 

 were so even in yield (growth) that little or no difference could be seen 

 in the different parts." 



As to the effect on trees, Mr. Yoemans says in his prize report in 1852, 

 " Some of the land I first drained had been planted with young orchard 

 trees and in the wettest places some trees died the first winter, and a greater 

 number the second winter ; and some young nursery trees on the same 

 ground were nearly thrown out of the ground by the frost. After drain- 

 ing it, I replaced the orchard trees and all have grown well and the first 

 crop of nursery trees, which I Avas compelled to remove to save them 

 before draining, have been replaced by others since draining and they have 

 succeeded perfectly so that I may now well say that if we desire to deprive 

 Jack Frost of his power to do harm, we should keep everything within 

 his reach as dry as possible." These statements are made wdth reference 

 to the hills of Miami stony loam soil in Wayne county. 



(9) Drainage reduces or presents erosion. Erosion is the washing of 

 the soil as the drainage water flows down the slope. A saturated soil is 

 in the right condition for erosion to be most serious. On the other hand, 

 thorough drainage permits part of this excess to be drawn off beneath the 

 surface in channels provided for it and which are not subject to such 

 injury. Further, on clay soil where the injury is liable to be the result of 

 the water flowing away because it cannot readily penetrate the surface 

 soil, this effect is reduced by the changes in the physical condition of the 

 soil resulting from drainage — as mentioned above — so that much more 

 of the rainfall is absorbed and thereby retained for the use of plants. 



(10) Drainage increases the yield of crops. This is, of course, the 

 obvious purpose of drainage as applied to agriculture. It is one of the 

 two fundamental purposes of drainage, the other being increased health- 



