QUESTION NO. 4
Reply by Hon. D.P.H. Liao, CBE, JP,
Secretary for District Administration,
to a question by Dr. the Hon. Henrietta IP Man-hing, OBE, JP,
in Legislative Council on 14 January 1987
QUESTION: Will Government inform this Council how many South China Pine trees in the territory have been affected by the pine-wilt nematode and what measures will be taken to preserve this type of tree?
Sir,
Some one million South China Pines, representing
about 70% of the total stock of this species in Hong Kong,
have been affected by the pine-wilt nematode since its
discovery in this territory in the late nineteen seventies.
About one third of the affected trees have died
and the remainder will probably die in the next few years.
So far, no effective chemical or biological
method of controlling this pest has been established, either
in Hong Kong or elsewhere. The Agriculture and Fisheries
Department has been trying to limit or delay the spread of the
pest by cutting down and burning the affected trees. Tens of
thousands of trees have been dealt with in this way since 1980.
The gradual decline of the South China Pine, which
was planted as a pioneer species in the nineteen fifties, is
not an entirely unwelcome event since it will have the effect
of opening up the forest canopy and encouraging the growth
of native broad-leaved trees and shrubs. The ensuing mixed
broad-leaved vegetation will be more resistent to fire and
pest than the South China Pine.