a a 
Insects of Shade. Trees and Their Control. 33 
infested trees with lead arsenate (p. 11) while the worms are feeding 
and, preferably, soon after they are hatched from the eggs in the late 
spring. For strength of spray and method of applying it see pages 
20-30. 
The effectiveness of the campaign against this pest will be in 
direct proportion to the extent to which the immediate neighborhood 
participates in it. 
A full account of the bagworm is given in Farmers’ Bulletin 701 
of this Department which will be sent on request as long as the sup- 
ply lasts. 
CATALPA SPHINX.” 
Recognition of work.—Catalpa trees, the only kind attacked by 
this insect, are often found having their leaves rapidly devoured by 
caterpillars which, when full grown, are conspicuously yellow and 
black striped, 3 inches long, with a short horn near the hind end of the 
body (fig. 18, ¢, e, 7,4). Caterpillar droppings beneath a catalpa tree 
are another indication of their presence. In some seasons the leaves 
are completely stripped off entire trees or even groves by this insect. 
Habits and seasonal history—Around Washington, D. C., the in- 
sect completes two generations annually, three or four in the ex- 
treme South. On attaining full growth the caterpillars of the fall 
generation crawl down the trunk of the tree and into the ground 
where they pupate and spend the winter in that stage (fig. 18, 7). 
Late the following spring the large grayish brown moths (fig. 18, /), 
known as catalpa sphinx or catalpa hawk moths, issue from these, 
mate, and lay their eggs (fig. 18,@) in batches up to about a thousand 
on the underside of leaves, and sometimes in smaller batches on 
stems and branches. The young caterpillars hatching from these 
feed in groups for some time before scattering (fig. 18, 6, 6,). They 
molt before reaching full growth and pupating, and vary consider- 
ably in the markings, as shown in the illustration (fig. 18, e, f). 
Control.—Normally, natural agencies, such as small wasplike and 
flylike parasitic insects and insectivorous birds, keep this insect in 
check, so that it is not seen in a given locality for from one to several 
years. In some parts of the South the catalpa is grown specially 
for the purpose of attracting the sphinx moth, for its caterpillars 
are highly esteemed there as bait for fishing. Occasionally, however, 
natural agencies fail to exercise satisfactory control and then the 
artificial killing of the caterpillars with poison spray, like lead 
arsenate, becomes necessary. The method of application of the 
spray is given on pages 20-30. 
Farmers’ Bulletin 705 contains a full account of this insect and 
will be sent on request as long as the supply lasts. 
13 Ceratomia catalpue Bdvy. 
5692°—20-——_3 
