— 
Insects of Shade Trees and Their Control. "61 
borers. This is a neighborhood or community problem, and to in- 
sure that the work is thoroughly done and in good season it must be 
enforced either by community ordinance or by aroused public senti- 
ment ard understanding. 
THE PARANDRA BORER.” 
How injurious —Although primarily breeding in utility timber, like 
telephone and telegraph poles, and other structural wood in contact 
with the ground or in moist situations, this insect is frequently found 
in the eastern half of the country seriously injuring all kinds of 
mature shade trees. This injury is at the base, and in windstorms 
trunks and branches thus weakened break off easily. This insect 
probably accounts for a greater percentage of destroyed bases of 
shade trees than any other. 
Character of work and habits of the insect—The adult, a rather 
large brown beetle, flies during the month following the blossoming 
of the chestnut, laying large numbers of eggs deep in the heart- 
wood wherever this is exposed. In this wood the grubs live as such 
for three or four years before changing to pupe. They feed gre-- 
gariously, completely honeycombing the wood and packing the mines 
with granular frass. The oval pupal cell is constructed in the wood, 
plugged behind with a wad of fibrous frass. Pupation takes place 
about a month before the adults emerge. 
A small wound near the base or in the larger branches of living 
trees offers a place of entrance for the young grubs which, penetrat- 
ing the heartwood, continue to feed until nothing remains but a shell 
of sapwood. Under certain conditions the adults do not emerge but 
mate and lay eggs in the same cavity in which they are working. 
Often the wound where they gained entrance heals over and shows no 
sign of their presence. 
Remedies. —As it is very difficult or frequently impossible to locate 
points on the tree where this insect is working, remedial measures 
must be directed toward prevention of the injury. All scars, fresh 
wounds, or injuries exposing the wood should be painted (p. 14-15) 
or so treated that no decay can start and that they quickly heal. Old 
cavities should be thoroughly cleaned and filled with concrete, care 
being taken that all wood showing any trace of grub-made mines 
is removed. 
TWO-LINED CHESTNUT AND OAK BORER.” 
How injurious —The sudden death of sickly and healthy chestnut 
and oak trees is most often traceable to injury by the two-lined chest- 
nut and oak borer, as this is their most serious insect enemy. As 
high as 75 per cent of these trees have been killed off by it in some 
33 Parandra brunnea Fab, 8 Agrilus bilineatus Weber, 
