BEET WORMS AND THEIR REMEDIES. 
21 
the worms crawl out and are thus exposed, the blackbirds congre¬ 
gate and help to rid the farmer of his hungry foes. 
Parasites. —The insects which live within the worms are many 
in kind and number. The maggots of several kinds of flies attack 
them. Wasp-like insects, both large and small, help in the good 
work. Two species of the larger kinds (. Ichneumon longnlus and 
Amblyteles subrufus ) have been reared at the Station while the 
worms at Denver two years ago were very largelyparasitized by a 
tiny insect belonging to the genus Copedosoma. Plate IV, Phg. 4. 
Counts were made from those reared from several worms and gave 
in individual cases from one to two thousand. So many of the 
worms were overcome by these agencies that there was no recur- 
rance of the pest. 
REMEDIES. 
There are two methods by which injuries may be controlled. 
One is preventive and aims to forestall trouble, and the other 
tends to lessen losses after the injuries are noticed. 
Preventive .—Early fall plowing will almost surely prevent 
the presence of worms in the field, for it leaves no vegetation on 
which the eggs may be laid. In the case of alfalfa, plow to the 
depth of three or four inches in September. This will not only 
prevent the pest, but will give the young foliage time to rot and 
furnish nourishment for the young beets. After plowing, harrow 
or otherwise treat the field so that it will be kept bare until win¬ 
ter sets in. 
Date fall plowing is almost equally beneficial for it turns the 
young worms under so deeply that they seldom come to the sur¬ 
face or else it exposes them in such a way that they fall an easy 
prey to the watchful birds or the inclement weather. 
Clear away all rubbish from the borders of the field. Such 
collections furnish the best kind of shelter for the worms over 
winter, from which they may invade the growing crop. 
If the field has not been plowed in the fall for any reason, it 
should be thoroughly examined for the presence of the pest in the 
spring. This may be done by examining under any object which 
may be laying on the ground. It would be well to lay bits of 
board or shingles in different places and look under them every 
few days for worms. 
Alleviative .—If the worms are present in the fields in the 
spring, they may be almost surely checked by one of the following 
practices: 
Spray heavily with Paris green or other arsenical mixture a 
growing patch of alfalfa or grass, mow it close to the ground and 
