CO129-511-25 Destruction and collection of pine tree caterpillars 10-12-1928 - 1-1-1929 — Page 6

Cahy (clony kull You -3

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Imperial Bureau of Entomology

Director:

GUY A. K. MARSHALL, C.M.G., D.Sc., F.R.S.

Sir,

Assistant Director:

S. A. NEAVE, D.Sc.

Head Office at-

BRITISH MUSEUM (NATURAL HISTORY),

1

20JEC 1928

OF

CROMWELL ROAD, LONDON, S.W. 7

19th December, 1928.

6

I have the honour to acknowledge the receipt of your

letter of the 10th December (No.52959/28) with reference to the ravages of the Pine Tree Caterpillar (Dendrolimus punctatus in

Hong Kong.

2.

It is doubtful whether any better measure against this

pest can be suggested than that which is already being employed, namely, the collection and destruction of the caterpillars, provided that there is a sufficient supply of cheap labour to make this course feasible. I should doubt, however, whether the reduction of the pest in 1925 and 1926 was due to the collection and destruction

of the caterpillars in 1924, or to unfavourable weather conditions.

It is more probable that it was produced by an increase of the

parasites and other enemies of the insect.

3. In a comparatively recent paper dealing with a nearly

allied caterpillar that attacks pines in Cyprus, Mr. D. S. Wilkinson

suggested that the collected caterpillars should not be destroyed,

but should be kept under conditions that would prevent the ultimate

emergence of the moths, but would enable the parasites to escape, for

it is obvious that when destroying the caterpillars indiscriminately

a number of beneficial parasites would also be killed. I enclose a

copy of Mr. Wilkinson's paper in case it may be of use to the

authorities in Hong Kong.

4.

The moth occurs also in Northern India, and I am writing

to