Vietnam Journal of Forest Science Number 2 – 2006

1. Five new species of Maclurochloa identified in Vietnam on the basis of morphological characteristics

Nguyen Hoang Nghia, Tran Van Tien

Forest Science Institute of Vietnam

Summary

Based on morphological characteristics (culm, branch, culm sheath, leaf) and flower anatomy, a key to the species of the Maclurochloa genus in Vietnam has been determined. Two species have one style (containing two stigmas) with one stigma originating from the top of the ovary. These are Maclurochloa sonduongensis sp. nov. with style and stigma having a filamentous form and Maclurochloa locbacensis sp. nov. with style and stigma having a flat form. Three species have one style originating from the top of the ovary. For Maclurochloa tantraoensis sp. nov., two stigmas originate from the top of the style while the third stigma originates from one of the other two stigmas. For Maclurochloa trangdinhensis sp.nov., three stigmas originate from the top of the style and these show the filamentous form while Maclurochloa tonkinensis sp.nov. also has three stigmas originating from the top of the style but these have a filamentous form. The key to the species is as follows:

A. One style (including two stigmas) and one stigma originating from the top of the ovary

B. Style and stigmas show filementous form………………… M. sonduongensis

B/. Style and stigmas show flat form ………………………….M. locbacensis

A/. One style (including three stigmas) originating from the top of the ovary

C. Two stigmas originating from the top of the style and a third stigma originating from one of the other two stigmas ………………………………………… M. tantraoensis

C/. Three stigmas originating from the top of the style

D. Stigmas show filamentous form ……………………… M. trangdinhensis

D/. Stigmas show flat form ……………………………… .M. tonkinensis

Keywords: Maclurochloa, species—identification

 

 

2. Preliminary results on the use of frankia bacteria to establish coastal plantings of Casuaria equisetifolia

Pham Quang Thu

Forest Science Institute of Vietnam

Summary

Casuaria equisetifolia reforestation on coastal sand dunes is very difficult because moving sand buries trees, and dry climatic conditions cause tops to wither and trees to die. Inoculating trees with Frankia bacteria leads to a symbiotic relationship to fix biological nitrogen, making trees drought resistant and leading to better growth on low nutrient soil. According to Leonard pot and nursery garden trials, three strains which have a good symbiotic effect are FrHN1, FrNA1 and FrQB5. Young trees which were inoculated with Frankia in a nursery garden had high growth and root diameter, better than a control treatment. Planting Casuaria equisetifolia inoculated with Frankia or adding 0.1 kg Frankia/per tree in coastal areas can reduce the rate of tree death and increase tree growth rate. The method of adding Frankia to young trees in the nursery garden gave the best result.

Keywords: Frankia, Casuaria equisetifolia, coastal revegetation

 

 

3. the market for wood products and wood material exports in Vietnam

Cao Lam Anh, Hoang Lien Son

Forest science institute of Vietnam

Summary

Timber and timbers products processing industry has continuously developed, in 2004 export turn-over of this sector has reached over 1 billion US dollars ranked the 5th among other export sectors in Vietnam. Beside the situation of timber scarcity, this sector is now facing the heated competition from the increased import sources due to the open economy. In the frame of tariff agreement (AFTA) and after the event of Vietnam joining WTO, the reduction of tariff on forest products import will create more competitive pressure over the sector in the next period. The research used issues from data and relevant information to analyse generally the market and marketing of timber and timber products in Vietnam.

Key words: Timber export, wood material, market of timber products

 

 

4. Research on chemical products for replacing termiticide TM 67

Le Van Lam and Ha Thi Thao

Forest Science Institute of Vietnam

Summary

After collecting the wood preservatives which have been used in Vietnam, the authors analyzed and determined the roles, properties and functions of the three components of preservative, the most important part being the effective termiticide.

By studying the chemical properties and the physiological mechanism of application of the product to termites, the following results were obtained:

All the substances are toxic to termites (a dosage of thousands of milligrams can kill many termites).

The substances kill termites by a contact mechanism, the toxic molecules pass through the skeleton of termites, and infect the digestive tract and blood circulation.

The effective substances are water soluble in water and become toxic to many species of termites by the infective mechanism.

Chemical compounds with these properties were collected and tested as replacements for termiticide TM 67. Three criteria were applied to test the effect of preservative firstly by desk research and then by field testing. Two preservatives, A and C, with the active ingredients NaF and CuF2, can meet the objectives of project.

Key word: Chemical products, termiticide

 

 

5. Results of a study to build production plantation models in Son La province

Vo Dai Hai, Tan Van Phong

Forest Science Institute of Vietnam

Summary

Development of production plantations in north-west provinces is the trend in Vietnam. This research is part of research and development on planting production forests which have economic, social and environmental value in northern mountains. It is part of a program of scientific and technical research as a basis for the development in the northern mountainous countryside. The research built a 19 ha production plantation model, in which 8 ha represented a plantation of large trees, 7 ha was a plantation of small trees and 4 ha was a non-timber products plantation. The model was built in 2003 and 2004 in Chieng Mung commune in Mai Son district and Chieng Bom commune in Thuan Chau district, Son La province. The first assessment shows that all trees in the model have a high survival rate and growth and quality of trees are good. This model showed real economic and social benefits of production plantations.

Keywords: plantation model, production plantation

 

 

6. test of hybrid acacia clones as a basis to propose some prospective acacia clones

Pham The Dzung, Nguyen Tran Nguyen, Ngo Van Ngoc

Forest Science Institute of Vietnam

Summary

A test of hybrid acacia clones from natural hybrid trees was carried out in Tan Tao plantation, near Ho Chi Minh City. The results reaffirmed that all the hybrid acacia clones grew faster than their parent species under the same conditions. Four hybrid acacia clones – numbers 1, 3, 4, and 8 were chosen from 10 test hybrid acacia clones. These were best in terms of diameter, height and volume growth. These clones will be used as research material in the next test. Meanwhile, they will be used for afforestation.

Keywords: Progeny test, hybrid acacia clones

 

 

7. Research into water requirements of individuals and populations of acacia and eucalyptus in plantations in Vietnam

Do Dinh Sam, Pham Ngoc Mau, Nguyen Thu Huong

Forest Science Institute of Vietnam

Summary

A research study was conducted into characteristic water requirements of individual trees and plantation populations of E. urophylla, E. camaldulensis, A. mangium, and A. auriculiformis in Doanhung (Phutho province) and Songmay (Dongnai province). The water requirement indicators are transpiration intensity, water absorption capacity of leaves, water requirement of leaves and the water capacity of the forest. The results showed that transpiration intensity of E. urophylla is higher than A. mangium and transpiration intensity of E. Camaldulensis is also higher than for A. auriculifomis. The water requirement of leaves follows the same rule. The transpiration intensity and the water requirement of leaves in eucalyptus depend on age and site conditions. These indicators have a higher value in the south than in the north. The transpiration level in E. urophylla plantations is much lower than in A. mangium because of the smaller leaf canopy. There is not much difference between E. camaldulensis and A. auriculifomis. The water capacity of individual and plantation populations is much lower than their transpiration levels.

Keywords: Transpiration intensity, water absorption, transpiration level.

 

 

8. Influence of planting density and fertilizer on the growth of P.caribaea var.hondurensis and E. urophylla plantations in Dai Lai – Vinh Phuc

Nguyen Huy Son

Forest Science Institute of Vietnam

Summary

On a feralitic soil developed on a clay layer in Dai Lai, Vinh Phuc, E. urophylla reaches its best growth rate with a bed-dressing application and top dressing in the second year including: 100g NPK (5:10:3) combined with 200 g microorganisms and 100 g lime powder. Until the third year, applying 150 g NPK (5:10:3) for additional fertilizing in combination with 300 g superphosphate or 200 g NPK in combination with 100 g lime powder, still has an obvious effect. The average volume of timber ranges from 17.51 to 17.62m3/ha.year after 5.5 years. P.Caribaea var. hondurensis reaches its highest growth rate when the bed-dressing is applied and top dressing is applied in the second year, including 200—300 g superphosphate in combination with 200 g of micro organism. The additional fertilizer in the fifth year also has an obvious influence on growth, in terms of both diameter and height – the best ratio is 300 g superphosphate combined with 300 g microorganism. Over this short time frame (two and a half years), there was no difference between the growth rates of P.Caribaea var hondurensis and E. urophylla. The research needs to be continued for longer to reach a more definite conclusion.

Keywords: E. urophylla plantation, P.Caribaea var. hondurensis plantation, Dailai-Vinhphuc

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