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Hypsipyla Shoot Borers of Meliaceae in Vietnam Nguyen Van Do 1 Abstract Meliaceous species do not constitute much of the 300 000 ha of forestry plantations in Vietnam. Chukrasia tabularis A. Juss. is an important native species of great value for high-grade timber but has now been banned from logging. Small areas of the exotic species, Khaya senegalensis (Desr.) A. Juss. and Swietenia macrophylla King have been planted. C. tabularis and Toona sureni (Blume) Merr. seedlings in nurseries have been damaged by shoot borers, presumably Hypsipyla robusta (Moore) and a number of other species. No research on H. robusta has been conducted in Vietnam. VIETNAM extends from 6°N to 23°N and is located in the Southeast Asian monsoon region. Due to its central location in Southeast Asia, the flora of Vietnam is characterised by a number of endemic species as well as many species from the nearby Indian, Chinese and Himalayan regions. Although an inventory of the flora of Vietnam has not been completed, more than 7000 species from 1850 genera and 267 families have been recorded. Among the 1000 species that can produce wood and timber, only a few species yield sufficient quantity and quality of timber to be commercially important. However, forests in Vietnam are of great environmental importance since they contribute towards regulation of stream flow and reduction of soil erosion in a country with more than 60% of the land area classified as mountains, hills or sloping land. Many forests also have scientific and tourism values. Until 1943, forest covered more than 40% of the total land area of Vietnam. The following period of the resistance wars and post-war period resulted in a large area of the forest being removed for war supplies, country reconstruction and raw materials for the rapidly expanding population. In this period, the forest resources were overexploited, leading to severe degradation. This led to a strong emphasis on forest plantation establishment, native forest conservation and regulated logging of native forest. 1 Forest Research Protection Division, Forest Science Institute of Vietnam, Chem-Tuliem, Hanoi, Vietnam 18 In Vietnam, there are about 1.6 million ha of plantation forests which are increasing in both the rate of planting and quality. Many species have been planted, including indigenous (e.g. Styrax tonkinensis Pierre, Manglietia glauca Blume) and exotic species (e.g. Pinus merkusii Jungh. & de Vriese, Pinus massoniana Lamb., P. caribaea Morelet, P. oocarpa Schiede, a wide range of Eucalyptus spp., Acacia mangium Willd., Acacia auriculiformis Cunn.). Some valuable commercial species such as Chukrasia tabularis A. Juss., Talauma gioi Chev., Tectona grandis Linn. f., Hopea odorata Roxb. have been planted to create a resource base for the developing wood peeling and veneer industries. Table 1 lists the area of plantation of the most important tree species. Plant breeding for higher wood production has become a leading concern for forest researchers and practitioners. Importance of Swietenioideae Species Chukrasia tabularis is no longer harvested from native forest due to a government ban in 1985, although some illegal logging still occurs. This species has high economic value (US$1000 per m 3 ) and has been used to make fine furniture and other commodities. Only a small area has been planted to species of Swietenioideae. The native species, C. tabularis has been used in enrichment plantings in Nghe An and other provinces with a total of 569 ha planted. Planting of C. tabularis is ongoing and proving
successful and is expected to have an optimal rotation length of 50 to 60 years. The Forestry Ministry has decided, as part of its program, to develop afforestation of high economic value tree species, to include three native species of Swietenioideae (C. tabularis, Toona sureni (Blume) Merr., T. sinensis (A. Juss.) M. Roem.) in the development of seed production areas. Some exotic species have been planted with Khaya senegalensis (Desr.) A. Juss. used mainly as an ornamental tree along streets and Swietenia macrophylla King established in small plantings in some areas. Table 1. Area of forestry plantations in Vietnam. Tree species planted Present area planted (ha) Eucalyptus camaldulensis Dehn. 94 674 Pinus merkusii Jungh. & de Vriese 62 333 Casuarina equisetifolia J.R. & G. Forst 25 906 Aleurites montana Wils. and Thea sasanqua Pierre 21 175 Pinus kesiya Royle ex Gorden 16 468 Anacardium occidentale L. 16 216 Melaleuca cajuputi Powel. and Rhizophora sp. 13 252 Styrax tonkinensis Pierre 12 692 Manglietia glauca Blume 12 230 Pinus massoniana Lamb., 11 889 Acacia auriculiformis Cunn. 6 347 Dipterocarpus sp. and Tectona grandis Linn. f. 5 818 Cinnamomum cassia Blume. and Illicium verum H. 4 131 Cunninghamia lanceolata (Lamb.) Hook 1 558 Melia azedarach Linn. 1 022 Chukrasia tabularis A. Juss. 569 Catanopsis spp. 398 Madhuca pasquieri H. Lec. 229 Total 306 907 There have been some reports of insect pests on C. tabularis seedlings in nurseries. Local workers have reported leaf eating caterpillars and shoot borers but their identification has not been verified. 19 Hypsipyla robusta Research and Future Directions There has been no research into Hypsipyla robusta (Moore) in Vietnam. Even though the dominant species in some natural forests belong to the Swietenioideae and they have high economic value, studies on their insect pest, especially H. robusta, have not been carried out for a number of reasons. Firstly, there are no funds available for basic research on forest insect pests of tree species that are not widely planted. Instead, the limited funds are directed towards applied studies on control of the main insect pests of plantation species that have already been planted (e.g. Pinus spp., Eucalyptus spp., Manglietia glauca, Styrax tonkinensis and cashew). Secondly, species of Swietenioideae have usually been established in mixed species or forest enrichment plantings and have not incurred destructive levels of insect damage. However, if species of Swietenioideae are to be planted widely and in open plantings, their insect pests are very likely to become a problem. It has been reported that H. robusta destroyed young Toona sureni (Blume) Merr. in nurseries in central and southern Vietnam. However, shoot borers collected from T. sureni in these areas in a subsequent year were identified as Zeuzera sp. Research directions in the future include: • surveying the insect pests of Meliaceae, particularly species of high economic value that are being used in new forestry projects; • participating in a regional network to exchange findings, experimental approaches and techniques in order to improve our knowledge of the biology of H. robusta and measures for its control; • collaborating with entomologists in Vietnam and overseas to carry out studies on insect pests of Meliaceae; • ensuring that the knowledge and experimental techniques for the study of H. robusta, as discussed at this workshop, will be properly applied in Vietnam.
Page 1 and 2: Hypsipyla Shoot Borers of Meliaceae
Page 3 and 4: Mayhew and Newton (1998) have revie
Page 7 and 8: Table 1. Summary of current and pas
Page 9 and 10: 26° 21° WEST BENGAL (INDIA) PACHA
Page 11 and 12: The only harvesting of Swietenioide
Page 15: H. robusta. From that time onwards,
Page 19 and 20: them are species of the subfamily S
Page 21 and 22: T. ciliata grows in dry deciduous f
Page 23 and 24: Table 1. Area of forestry plantatio
Page 25 and 26: S. macrophylla and Swietenia mahago
Page 27 and 28: plantings of S. macrophylla, K. sen
Page 33 and 34: Table 1. Major plantation areas and
Page 37 and 38: mixing seedlings of S. macrophylla,
Page 41 and 42: of these species, plantings have be
Page 43 and 44: 45 Table 5. Continued. Description
Page 45 and 46: 47 Table 6. Description of on-going
Page 47 and 48: locations were generally poorer, wi
Page 51 and 52: growth response and resultant form
Page 53 and 54: Mr David Spolc (University of Queen
Page 55 and 56: Haley, C. 1954. Forestry in Tropica
Page 57 and 58: Gross Domestic Product, a contribut
Page 59 and 60: A number of parasitoids have been b
Page 61 and 62: A Review of Hypsipyla grandella Zel

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