60 THE SUGAE-BEET WIREWORM. 
beets and wireworms were killed. It was used several times more, 
and in weakened solutions, but invariably the results were the same. 
By this time the season was so far advanced that experiments along 
this line had to be given up for the year. The conclusions that seem 
justified from this experiment at the present time appear to be that 
the wireworms may be killed by applications of a solution of potassium 
cyanid to the soil, but that the beets are also killed by the same treat- 
ment. It is a question whether a certain strength of cyanid can be 
found which wiU kill the wireworms and spare the beets. Possibly, 
however, the wireworms can stand a stronger application of the 
cyanid than the beets can. As this is the only insecticide which has 
given promise of good results against the wireworms, it will receive 
further careful tests. The possible effect of this cyanid on the soil 
and future crops is also an interesting question, and one which will 
have to be investigated. There is a possibility that this cyanid 
might be applied directly after the crop is removed and before the 
wireworms have become dormant for the winter. 
EXPERIMENTS WITH POISONED BAIT AGAINST THE WIREWORMS. 
In the experiments in the use of poisoned bait against the wire- 
worms the points which were chosen for solution were, (1) to find a 
substance for the bait which would be very attractive to the wire- 
worms, and (2) to find a poison to go with it which would certainly 
kill the larvae. Thus far success has not been attained in the solution 
of either. The following materials have been experimented with as 
bait: 
Beans. Bran. 
Com. Alfalfa meal. 
Commeal. Shredded beets. 
Of these the only ones which have proved attractive enough to be 
used with the poisons were beans, corn, and shredded beets. Series 
of experiments were conducted using each bait with every poison, 
and checks were employed in each. The following poisons were used: 
(1) Lead chromate. (4) Paris green. 
(2) Potassium cyanid. (5) Lead arsenate. 
(3) Strychnine. (6) Zinc arsenite. 
The first four named, being insoluble, were applied to the bait in 
paste form with flour. In the case of every poison except the cyanid 
the wireworms were observed eating the bait, and if they suffered 
any ill eifects from it they failed to show it to a noticeable degree. 
The bait containing the cyanid was eaten sparingly on account of 
its deterrent qualities. Wireworms were found dead in some of the 
cages in wliich potassium cyanid was used, but whether their death 
