DRAINING GRASS LANDS 



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ness in grass grown on drained soil than in grass grow- 

 ing on wet land. I have seen wonders done in Eng- 

 land and Scotland by drainage; there, at least, tiles were 

 the foundation of soil improvement. I have seen heaths 

 covered over w r ith little worthless heather, barren of 

 grasses or clovers, first deeply drained with tiles, then 

 limed and enriched and afterwards made into as splen- 

 did meadows as I have ever seen. Remember always 

 that clovers are the natural allies of grasses, and clovers 

 thrive with their roots in soil in which there is air as 

 well as moisture, since in no other soil can their roots 

 bear the nodules which carry the bacteria that gather 

 nitrogen from the air and thus enrich the soil for them- 

 selves and for their companion grasses. In any scheme 

 of soil improvement then let drainage go first. 



Depth to Underdraw. Drains laid deep do most good. 

 Here one must consider soil types and go as one must. 

 Sometimes one can not lay tile work deeper than 30"; 

 this depth will, indeed, give good results with grasses, 

 but not so good with clovers. I have laid them at all 

 depths from 2 to 12', and now we lay them, as nearly 

 as possible, 4' deep. In draining very rich soil that is 

 to bear pasture grass alone, however, it may be that 

 shallower drains will give better results; thus, in Hol- 

 land, I have observed that men seek to keep the water 

 level about 16" below the surface of the soil. Indeed 

 they often have their ditches so arranged that they can 

 pump water into them so that it will seep back into the 

 land and keep it moist in times of drouth. That land, 

 however, seems unnaturally rich, and some unexplained 

 plan of nature keeps it filled with nitrogen. No doubt 



