244 



Bulletin 237. 



abundant. At times it has been superabundant and there has been con- 

 siderable drainage across these plats, both over the surface in times of 

 downpour and by percolation at other times. On July 28-29, when the 

 earlier notes were taken, numerous plats, or parts of plats, were found 



Fig. 93. — Plat I $16. Culture treated seed. No manure. Alfalfa and weeds from 



four square feet. 



Fig. 94. — Plat 150.^. Culture treated seed and manure. Alfalfa and weeds from four 

 square feet. ( Note. In comparing Fi^. 94 with gi, it should be borne in mind that 

 all the plats soon became inoculated from natural causes, probably owing to proxim- 

 ity to plats to which soil had been applied. See page 162 near bottom-.) 



that seemed to produce no nodules, but now (October 30") nodules seem 

 to be quite evenly distributed over the whole area. No doubt the lay of 

 the land and the manner of drainage brought about ibis result. 



