Hypsipyla Shoot Borers of Meliaceae in Sri Lanka - Australian ...

Hypsipyla Shoot Borers of Meliaceae in Australia
M.W. Griffiths 1 , F.R. Wylie 2 , R.B. Floyd 3 and D.P.A. Sands 1
Abstract
Red cedar, Toona ciliata M. Roem, has been a highly favoured timber species in Australia since
the time of European settlement. Rapid and indiscriminate felling during the 1800s led to concern
about the future supply of this timber, and various attempts were made to grow the tree in natural
forests and plantations. Some of the first silvicultural work on any species in Australia involved
experimental plantings of young trees into former cedar areas in the late 1800s and early 1900s.
These early plantings were unsuccessful, with the failure attributed primarily to damage caused by
the tip boring moth, Hypsipyla robusta Moore (Pyralidae, Phycitinae). The Queensland and New
South Wales forest services have tried to identify the conditions that minimise H. robusta damage
and therefore allow successful production of T. ciliata. However, damage from H. robusta
remained a problem, and only a few plantings produced trees with good overall growth rates and
form. The outcomes of these trials are summarised in this paper. Despite the early recognition of
the critical role of H. robusta in limiting growth of T. ciliata, until recently there have been few
attempts to investigate the taxonomy, biology, ecology or life history of H. robusta in Australia.
Work undertaken to date is described, and directions for future research are identified.
Overview of the Forest Industry
THE forest industry is an important part of the Australian
economy, comparable with the barley, cotton
and sugar industries in terms of gross value of production
(Table 1). The industry comprises approximately
4% of the total gross value of production for
farming, forestry and fishing.
Australia is a net importer of forest products. In
1994–1995, Australia imported forest products
valued at AU$3 billion, while exports for the same
period were valued at AU$1 billion, or 5% of the
value for the rural sector (ABARE 1996b). In 1994–
1995, the forestry and logging industries employed
12 000 people, accounting for 3% of the workforce
employed in agriculture, forestry and fishing, and
0.15% of the total industrial workforce (ABARE
1996a). Forest products industries employ an
additional 61 000 people (ABARE 1996b).
1 CSIRO Entomology, PMB No 3, Indooroopilly Queensland
4068, Australia.
2 Queensland Forestry Research Institute, PO Box 631,
Indooroopilly Queensland 4068, Australia. (Also current
address for M.W. Griffiths)
3 CSIRO Entomology, GPO Box 1700, Canberra ACT
2601, Australia.
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Table 1. Estimated gross value of production in selected
primary industries. a ABARE (1996a); b Sar (1993);
c ABARE (1995) – average gross value 1992–93 to 1994–95.
Gross value of production
(AU$ millions)
1991–92 1992–93 1993–94 1994–95
Crops a
Wheat 2097 2894 2867 1958
Barley 693 802 845 572
Sugar 590 805 947 1257
Cotton lint 862 665 631 804
Livestock a
Beef 3802 3839 4353 3960
Wool 2980 2569 2459 3264
Fisheries products 1376 1493 1686 1745
Forestry 712 b 738 b 967 c 967 c
Total 23 474 24 658 26 280 26 302
Australia’s forestry resource base comprised
approximately 41 million ha of native forests and
1.1 million ha of plantation forests at March 1995
(ABARE 1996b). The majority of plantations were of
softwood species, predominantly the exotic Pinus
radiata which occupied approximately 726 000 ha
(Table 2). Approximately 14% of plantation land was