30 MISC. PUBLICATION 6 2 6, U. 



S. DEPT. OF. AGRICULTURE 



Burdock Leaf Miner 



The burdock leaf miner (Agromyza 

 maculosa Malloch) is at times destruc- 

 tive to the leaves of chrysanthemums, 

 although it is primarily a pest of bur- 

 dock. The tiny white maggots feed 

 between the upper and lower leaf sur- 

 faces and make a blotch mine (fig. 48). 

 Several maggots work together in one 

 mine. The part of the leaf that is 

 mined turns brown and eventually dies. 

 The adult is a tiny two- winged fly. 



Figure 48. — Blotch or blisterlike mine 

 on chrysanthemum caused by the bur- 

 dock leaf miner. Slightly reduced. 



Treatment. — Hand-pick and destroy 

 the mine-infested leaves by burning 

 them, to prevent the insects from com- 

 pleting their development. This is 

 usually all that is necessary. If the 

 infestation is heavy, however, spray with 

 a nicotine sulfate and soap solution when 

 the mines are just beginning to form. 



Prevention. — Raking and burning all 

 dead leaves below the plants late in the 

 fall or very early in the spring will dis- 

 pose of some of the overwintering stages. 



Spittle Buss 



The spittle bugs or froghoppers, al- 

 though not often sufficiently injurious or 

 numerous to do much damage, some- 

 times cause losses to chrysanthemums, 

 roses, and other plants. They are small 

 sucking insects of the famliy Cercopidae, 

 and there are a number of species that 

 occur on weeds as well as certain flower- 

 ing plants. Their name is derived from 

 the peculiar frothy material (fig. 49) 

 with which the nymphs cover them- 

 selves, and the squatty, froglike appear- 



Figure 49. — Spittle bug covered with 

 froth on a rose stem. Natural size. 



ance of the adults. They have a 

 number of local names, such as "frog- 

 spit" and "snake-spit." 



Treatment. — Spray with pyrethrum 

 or a nicotine sulfate and soap solution, 

 if there is evidence of injury. 



Prevention.— Burning infested weedy 

 areas near the garden in late winter 

 or early spring is of some value. 



Other Pests of Chrysanthemum 



Page 



Cutworms 2 



Yellow woolly bear 3 



Spotted cucumber beetle 7 



Asiatic garden beetle 21 



Stalk borer 34 



Rose chafer 66 



Thrips 74 



Termites 13 



Grasshoppers 9 



Tarnished plant bug 35 



Red spiders 11 



Slugs 16 



Snowbugs.- 17 



CLEMATIS 

 Clematis Root Borer 



The clematis root borer (Alcathoe 

 caudata (Harr.) ) attacks the fleshy roots 

 and infests the crown of clematis, 

 especially virgins-bower. It sometimes 

 hollows out the bases of stems, causing 

 the plants to show a lack of vigor and to 



