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TRUCK-CROP INSECTS 
E.W. Jones, Walla Walla, Wash., reports: "Baiting for wireworms with 
ground wheat ball baits was continued this month in fields heavily in- 
fested with Limonius californicus. From 1,061 baits planted during the 
month a total of 14,527 larvae were obtained. This is an average of 
13.7 worms per bait." 
Mr. Jones also reports that in laboratory studies on submer- 
sence of wireworms, "it has been found that large larvae (2 to 3 years 
old) (of Limonius canus) may be submerged for 6 1/2 months at temperatures 
of 9°, 15°, and 20° C without dying. The young larvae submerged shortly 
after hatching are alive after 6 months in the water at 9° C. A few 
young larvae lived in the water 83 days at 12.5° C., 56 days at tage 
49 days at 20° C., and 43 days at 25° and 30° C." 
F. H. Shirck, Parma, Idaho, states that larval—-migration studies on 
wireworms have been completed at that laboratory. From these studies it 
has been learned that" wireworms tend to spread themselves more or less 
evenly throughout the area within which they may be enclosed," and that 
larval migration "is not influenced by the presence or absence of food." 
It was also found that wireworms are not "able to smell or otherwise 
detect the presence of baits in the soil*** That so many wireworms will 
collect at a bait in a comparatively short time is an indication that 
these larvae are very active, since much of the soil traveled through 
yields presumably little food." 
In connection with the experiments in control of the sand wire 
worm (Horistonotus uhleri Horn.) at Fairfax, 5. C., J. N. Tenet reports: 
"Potatoes seem to be particularly susceptible to injury from the sandy-— 
land wireworm. Qn an experimental plot of the late spring potatoes, 
of approximately one-third acre, which was very heavily fertilized, the 
yield was only 5 bushels of marketable potatoes. The total yield was 
18 1/2 bushels, and of this total, 13 1/2 bushels were so badly marked 
with feeding punctures, or so underdeveloped, that they had to be thrown 
away. Without wireworms present, this plot should have easily yielded 
90 bushels of No. 1 potatoes," 
In the work with parasites, Mr. Tenhet says: "It has been dis— 
covered that approximately 8.5 per cent of all field-collected wireworms, 
this season, are parasitized by a nematode (Diplogaster sp.). This is 
particularly interesting on account of the extreme scarcity of records of 
wireworm parasitism. This nema has been taken from dead larvae and bred 
upon corn roots, decaying pea-vine hay, decaying crabgrass hay, decaying 
wheat bran, and decaying cottonseed meal. An attempt is now being made 
to reparasitize wireworms with nemas bred on the decaying organic matter," 
R. E. Campbell, reporting studies made by himself and assistants 
on the life history and habits of the wireworm Pheletes californicus 
Lec. at the Alhambra, Calif., field laboratory, says: "Of eggs laid in the 
Spring of 1930 (March or April), on Febr. 3, 1931, the larvae were divided 
Se lOO Te el eee 
