50 



thrown into the crowns and allowed to reach the soil. If with this the 

 best cultural conditions possible are maintained, such as good ventila- 

 tion and a frequent stirring of the soil, injury might be greatly lessened. 

 The free use of Buhach, or Persian insect powder, at the time when 

 the mature gall flies are seen filing about the greenhouses and upon 

 the windows, would also be of considerable value in lessening their 

 numbers. 



THE VARIEGATED CUTWORM. 



(Peridroma saucia Huebn.) 



Of all violet pests, other than those which have already received 

 special mention in this publication, cutworms of several species as well 

 as allied caterpillars of moths belonging to the same family, the Noc- 

 tuidae, and some related families, are most conspicuous. It is seldom 

 that greenhouses are entirely free from them, and the constant vigi- 

 lance of the florist must frequently be exercised to keep them under 

 control. The leaves of violets are particularly subject to cutworm 

 attack in the spring, after the new plants have been set out. 



The cutworms in houses may be produced from eggs laid by moths 

 which have flown in at open doors or windows, but more frequently 

 the} 7 are carried indoors with the soil in the fall, and they are most 

 apt to occur in beds in which grass has been permitted to grow, as 

 well as in houses immediately surrounded by dense growths of rank 

 grass and weeds. The reason for this is that a very considerable per- 

 centage of the cutworms which attack violets feed normally upon 

 grasses or weeds and it is upon these plants that the moths usually lay 

 their eggs. 



Cutworms, as is well known, are most voracious feeders, and in a 

 short time are capable of doing much damage to such small plants as 

 violets. Frequently they cut down whole plants of these and similar 

 ornamental flowers. 



What makes these insects difficult to deal with is their nocturnal 

 habit, their presence being seldom detected in the daytime, save by 

 their work, unless during cloud} 7 weather or in secluded dark places. 



A common insect met with in recent years on violet and a number 

 of other plants grown under glass is the variegated cutworm (Peri- 

 droma saucia). It is usually abundant nearly everywhere, and to be 

 found in fields and gardens, pasture land, vineyards, and orchards, as 

 well as in greenhouses. It is one of the best known of our numerous 

 cutworms, one of the most destructive, and appears to be the particular 

 species most often found on ornamental and other plants growing 

 under glass in conservatories as well as in cold-frames. During the 

 season of 1900 it was very destructive over a wide extent of territory, 

 but most conspicuous by its injuries in the Pacific States. Owing to 



