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JOURNAL OF ECONOMIC ENTOMOLOGY 
[Vol. 16 
tion was very heavy on the older plants that fall. The only measure 
aimed directly at control was a practice of the workmen to collect and 
kill all beetles which would crawl up the wire stakes after every syringing 
of the plants. This was done regularly during September, October, and 
November in 1921, and on some days over a thousand beetles were 
collected and killed in an hour. The beds were kept immaculately 
clean and free from dead leaves and trash, and manure water was 
applied instead of mulching the beds. Only a few beetles could be 
found here and there during 1922. 
A more intensive program than any of the preceding ones was carried 
on in an open-range of infested houses containing 40,000 plants at 
Doylestown, Pennsylvania. Sections of this place had been infested in 
1919 and 1920, but during 1921 the whole range with the exception of 
about 8,000 new plants was overrun by the beetles. An average of 15 
beetles to each plant in the badly infested houses is a conservative es¬ 
timate of the numbers present during June and July. 
The injury was so severe that it became impossible to produce salable 
flowers and the grower was obliged to stop his shipments to the markets. 
A series of fumigations with hydrocyanic-acid gas, as described in last 
year’s paper, was employed during the month of July while the plants 
were being “dried-off.” During these treatments the use of muslin 
curtains to separate sections of the open range proved satisfactory in 
confining the gas. The fumigations were quite successful for many dead 
beetles were found lying on the leaves and ground afterwards. After the 
plants were “cut-back” the surface layer of soil was scraped from the beds 
and in this removed material an average of three or four beetles per 
plant was found. The cut-back plants were sprayed with arsenate of 
lead at the rate of 4 pounds to 50 gallons of water to protect the swelling 
and breaking “eyes” as the florist terms the developing buds. As 
new foliage formed it was kept continually coated with a dust mixture 
containing 15 parts of calcium arsenate, 80 parts of sulphur, and 5 parts 
of powdered sugar. The dust applications were continued until the 
middle of November and were resumed in February 1922. About 1500 
pounds of dust were used during the fall of 1921. 
Starting in February 1922, wood ashes and tobacco dust were applied 
to the soil alternately at frequent intervals during the spring. Two 
carloads of each material were used. The absence of beetles at all 
times during 1922 has been in marked contrast with the large numbers 
present the preceding summer. Although a few beetles have been 
found occasionally, many searches lasting two or three hours have 
