8-2 
Indian Forest Records. 
[VOL. IX 
(4) With few exceptions damage by sapwood borers, heartwood 
or longieorn borers, shot-bole and pin-hole borers can be 
prevented by removal of the bark or by green conversion 
immediately after felling. 
(5) The damage is done within a period of 3 — 6 months from the 
commencement of attack, and its extent is dependent on 
the proportions in which the most destructive borers occur; 
for a pme infestation by one species rarely happens. Beyond 
this period the extent of the damage is not affected either 
by the length of time the tree stands girdled, or the timber 
is held in the log, or by subsequent methods of treatment 
{e.g., stacking, skidding, sun-curing, water-immersion). It 
is the work of single broods and is not extended by later 
broods of the same species. 
The follo'ndng classification gives a general idea of the different 
types of damage caused by boring insects in India and the conditions 
under which they are able to work. As a rule we have to deal with 
borers that do the damage in the grub or caterpillar form, and not 
as beetles or perfect insects: — 
Borers of Jiving trees. 
Moths — • 
1. Beehole Borers — 
(1) Cossidae, (2) Hepialidae, (3) ArbeJidae. 
Beetles — 
2. Longieorn Borers {Cerambycidae and Lamiidae). 
Borers of felled or girdled trees. 
Beetles — 
1. Longieorn Borers {Cerambycidae and Lamiidae). 
2. Flat-headed Borers {Buprestidae). 
3. Weevils (Curculionidae). 
4. Brenthidae, Lymexylonidae, Siricidae, etc. 
5. Shot-hole and Pin-hole Borers {Platypodidae and Xyleborinae). 
6. Sapwood Borers. 
7. Dry wood Borers {Bostrychidae, Cerambycidae). 
(i) Borers of livixg trees. 
The tunnels of this class of borers are constructed and inhabited 
during the course of a year. After the emergence of the mature 
insect the mouths of the galleries connected with the living bark are 
occluded and overgrown by the wood of subsequent years. Tunnels 
formed early in the life of the tree thus occm deep in the timber near 
the pith, and those made later in its life are situated nearer to the 
[ 228 1 
