62 HATCH EXPERIMENT STATION. [Jan. 



The Effects of Desiccation on Soil. 

 The practice of desiccation or drying greenhouse soils by 

 aid of the heat of the summer sun has been in vogue with 

 us for some time, for the purpose of observing what effect 

 such treatment would have on certain organisms. We have 

 already shown that the Sclerotinia or the drop fungus when 

 dried is greatly accelerated in its activity, which increases 

 to a great extent the amount of infection in the succeeding 

 crop of lettuce. The resting spores of many other plants 

 are undoubtedly affected in the same way. There are other 

 effects of drying on the soil which prove very destructive 

 to the development of lettuce plants, although we have not 

 observed this effect upon other species. On lettuce we 

 have observed this repeatedly, and the characteristic re- 

 sults of such drying are manifested in a stunted growth 

 and abnormally colored and worthless crop. The crop 

 scarcely ever attains more than one-third of its size. The 

 texture of the plants is poor, being thick and tough, and 

 inclined to crinkle. That this is caused by desiccation 

 alone is shown by the fact that wherever any drip from the 

 roof fell upon the soil during the summer rains, the plants 

 growing in such places were always normal. Distinctly 

 sharp lines can be observed in a lettuce crop grown under 

 such conditions, owing to the difference in development 

 brought about by desiccation and the presence of a small 

 amount of water due to dripping. Instances have come to 

 our notice where large houses devoted to lettuce have been 

 allowed to become quite dry, with the same result on the 

 crop as noted above. The remed}^ for this trouble is 

 obvious ; namely, not to allow the house to become too 

 dry in summer, but to keep the soil more or less supplied 

 with water. If such drying occurs, the soil can be entirely 

 renovated by applying hot water or steam to it, as we have 

 already shown more than once. 



Melon Failures. 



No trouble with plants has been more general in New 

 England the past season than that attending the growing 

 of muskmclons. In a great many cases this crop has been a 



