Circular No. 4. May 1907 



MASSACHUSETTS AGRICULTURAL EXPERIMENT STATION. 



WIRE WORMS. 



BY C. E. HOOD, B. S. 



This serious pest of field crops is a long slender grub, yellowish 

 white in color and with an unusually hard body. These wire worms, 

 so called because of their hard bodies are the larvae or younger 

 stages of the click-beetles or snap bugs. There are many species of 

 these, found under varying conditions. Some are not injurious, 

 while others do great damage to the roots of plants and to seeds, and 

 as they work in the ground out of sight it is very difficult to combat 

 them. 



The click beetles lay their eggs and from these the larvae or wire 

 worms hatch and commence feeding. They continue in this stage 

 for about two years when they go into the pupa stage, rolling them- 

 selves up in a little case of dirt. In three or four weeks they become 

 adult beetles but remain in the ground until spring when they 

 emerge and lay their eggs for another generation. 



Three different classes of remedies have been tried on these 

 insects, i. Protection of the seed. 2. Destruction of the larvae 

 (wireworms). 3. Destruction of pupae and adults. 



The first method consists of coating or soaking the seed in various 

 substances as tar, Paris green or kerosene, but the results are not 

 such as to recommend them generally. 



The destruction of larvae by clean fallow ; by planting of the so- 

 called immune crops ; and by insecticides has not proven as success- 

 ful as had been hoped for. 



The remedies which seem to be the most effective in the control of 

 this insect, are the destruction of the pupae and adults by fall plow- 

 ing and by traps. 



Much can be done towards checking the increase of wireworms by 

 fall plowing, as it has been found that if the pupa cases of the insects 

 are disturbed the insects in them are almost sure to die. The plow- 

 ing may be done any time after July 20, for by then all mature wire- 

 worms have changed to pupae. After plowing the soil should be 

 well pulverized. If this thorough cultivation be continued for three 



