ECONOMIC VALUE OF FUMIGATION 229 
methods for the destruction of scale pests. The in- 
creased cost of fumigation over spraying has, however, 
induced some orchardists in Southern California to 
resort to the cheaper method of spraying. Fumiga- 
tion is the only remedy considered at all effective for 
the red scale. ‘The amount of cyanide required to 
destroy black scale, if done at the proper time, is about 
one-half that required for red scale. In addition to 
my duties as Horticultural Commissioner, I am also 
Superintendent of Fumigation. I have been connected 
with the horticultural commission of Riverside County 
for the past six and a half years.—R. P. CUNDIFF. 
Arizona.—In July, 1900, I employed this treat- 
ment for the destruction of the date palm scale, Parla- 
toria vicirix, imported with a large consignment of 
some four hundred date-palm suckers from Algeria. 
We subjected the suckers to fumigations varying from 
0.3 to 0.5 per cent. gas. The foliage of the plants, 
being of exceptionally hard and impervious nature, 
was not injured.—Prof. R. H. ForseEs, Director Ari- 
zona Experiment Station. 
Arkansas.—I1 am convinced that the treatment 
with hydrocyanic acid gas is an excellent method and 
destined to become of general service. I have been 
recommending it to nurserymen on occasion, though 
entirely on the basis of knowledge derived from the 
reports of others, such as your own.—Prof. ERNEST 
WALKER, Entomologist Arkansas Experiment Station. 
Fumigation operations in Canada.—The following 
report was furnished the writer by Prof. William 
Lochhead, of the Ontario Agriculture College: In 
