ECONOMIC VALUE OF FUMIGATION 251 
insect life, that can but be deleterious to the tree if 
allowed to remain thereon in an active condition. For 
the past two years we have fumigated everything that 
we have sent out except evergeens, and so far have 
never detected any injurious effectts.—TuHE R. G. 
CHASE Company, JVurseries, New York. 
Utah.—We believe this is the most efficient treat- 
ment that nursery stock can be given. If the build- 
ing is air-tight and the chemicals are mixed in the 
proper proportion, it is undoubtedly destructive to all 
kinds of inseéts and no harm results to the stock. 
After putting gas into the building we leave our stock 
stand from one-half to three-fourths of an hour, then 
throw the double doors wide open, and allow the 
building to ventilate from fifteen to twenty-five min- 
utes before attempting to remove the stock. We 
believe it pays us to run all nursery stock through our 
cyanide house. We have treated from two to three 
hundred thousand trees annually for the past three 
years. In 1901 we expect to treat half a milllon. If 
one had more stock than this it would be advisable to 
build a larger house. We think it quite necessary to 
have the roots of the trees comparatively clean. If 
they are covered with dirt, especially clay soil, the gas 
may not penetrate to the insects, especially woolly 
aphis. Do not think our building cost to exceed $50. 
—VAN METER, HARNESS & Co., Proprietors Davis 
County Nurseries, Utah. 
Utah.—I have followed your directions for fumi- 
gating, which have proven very satisfactory. I have 
had no opportunity for experimenting with scale, but 
