56 INSECTS INJURIOUS TO VEGETABLES 



cutworm deterrent is certainly advisable. In any case, it should 

 be employed as a diluent for whatever arsenical is used. 



Hand methods. — On some plants it is next to impossible to 

 apply any but hand methods with good results. Experiments 

 in Washington State during 1900 demonstrated conclusively 

 that in some cases it required less time to shake or brush the 

 variegated cutworm from affected plants than to destroy them 

 by spraying or otherwise. 



In ordinary cases of cutworms in greenhouses they can be 

 held in check by hand-picking. It is the custom of some florists 

 to hunt for them at night with a lantern, when they are feeding 

 and can readily be discovered and destroyed. 



Treatment as an army worm. — When cutworms assume the 

 habit of traveling in armies they should be treated in the same 

 manner as advised against the fall army worm in pages which 

 will follow. 



The Fall Army Worm (Laphygma frugiperda S. & A.). — The 

 fall army worm or grass-worm feeds normally on grasses and 

 grains and weeds belonging to the grass family, but will attack 

 in its seasons of abundance almost any form of vegetation that 

 is encountered in its line of march. At such times it becomes 

 a pest in garden and orchard, on lawns and in greenhouses, as 

 well as in pastures and in fields of grain. The moth is quite 

 unlike that of the common army worm and very variable, there 

 usually being two distinct forms, a dull gray and an ornamented 

 form (fig. 30, a and h) . The hind-wings are glistening white 

 with rosy reflections. The wing expanse is from an inch to an 

 inch and three-eighths. The eggs are deposited in clusters of 

 from fifty or more, often in two or three layers. The mass is 

 covered with down from the body of the moth. The differences 

 between this and the true army worm are shown by figures 30, a, 

 ^ox and 31. 



This insect is undoubtedly native to North as well as South 

 America. Its greater abundance in semitropical regions in- 

 dicates that it was originally, although not in very recent times, 



