328 Gardening 



mustard and may be destroyed. In this way crops of 

 cabbage are protected in spring. In the autumn late 

 crops of mustard will attract the bugs at times when 

 other food may be scarce. 



(3) Clean culture. The advice given for clean culture, 

 under methods of combating the common squash bug, 

 will be helpful also in keeping the calico bug under 

 control. 



Gardeners living in the zone just north of the present 

 range of the insect should keep a sharp watch for its 

 appearance. Determined efforts should be made to pre- 

 vent its further spread. 



THE BURROWING INSECTS 



The larvae of many insects live within the plant and 

 cannot be killed in their feeding stage by poisons or 

 sprays. To combat them it is necessary, therefore, 

 to keep the adults from laying eggs among the plants, to 

 destroy them when they are outside the plant, or to 

 remove them from their tunnels by hand and kill them. 

 Several kinds of burrowing insects are troublesome to 

 garden plants, and some of these are often very injurious. 



The radish maggot. The roots of radish and cabbage 

 plants are attacked by " maggots," which eat grooves in 

 them or even tunnel into the inside. Young cabbage 

 plants may thus be killed, and infested radishes are 

 stunted and made worthless as food. 



The adult of this maggot is a fly (somewhat smaller 

 than the common house fly) which appears in the spring. 

 It lays its eggs in the soil, usually near plants of the 

 radish or the cabbage, and the eggs hatch in from 3 to 



