Research Report

# Erythrophloeum fordii Oliver: Ecology and silviculture in Vietnam

Chaw Chaw Sein
Ralph Mitlöhner
Pages: 18
OPEN ACCESS
https://www.jstor.org/stable/resrep02133

1. (pp. i-ii)
2. (pp. iii-iv)
3. (pp. v-v)
The authors
4. (pp. vi-vi)
5. (pp. 1-1)

Erythrophloeum fordii, the so-called ‘ironwood’, is a tree species indigenous to Vietnam which produces high quality timber. This species has been exhausted by heavy exploitation and deforestation and is rare in Vietnam. Aside from its economic objectives, the Government of Vietnam’s Five Million Hectare Reforestation Project aims to protect the environment, restore forest ecosystems and conserve biodiversity. The preservation of native indigenous species is of special significance to the country (FSIV and JICA 2000)....

6. (pp. 1-2)

Botanical name: Erythrophloeum fordii Oliver

Family: Caesalpiniaceae

Subfamily: Caesalpinioideae

Vernacular/common name in Vietnam: Lim Xanh

Erythrophloeum fordii is a large, evergreen tree species which is capable of reaching a height of 37–45 m and a diameter of 200–250 cm. The stem is rounded with dark brown bark, which is square cracking, has many conspicuous lenticels and can be peeled off in scales. The base of the stem has a small buttress. The foliage is thick and green all year round. The leaves are bipinnate and ovoid, with a rounded base and pointed tip. Their upper layer is dark...

7. (pp. 2-3)

Seeds should be collected from mother plants that exhibit good growth patterns, have thickly proportioned foliage, a round, straight trunk of 40 cm diameter or more, and have no pests or other natural flaws. The optimum time for seed collection is as soon as the seeds reach maturation. This happens in October–December, when the skin of the fruit is a grey brown and the seeds have turned shiny black and have hardened. If not collected then, the seed may over-ripen and not germinate well, or be susceptible to insect attack if fruits or pods stay on the tree too...

8. (pp. 3-5)

Following appropriate preparation the seeds can be sown either in pots or in beds.

Sowing into pots. Use a pointed stick to drill a hole 1–2 cm deep in the soil in the middle of the pot, then put in a seed and cover it with soil. The number of seeds per pot determines the security of successful germination: e.g. 3 seeds 40–60%, 2 seeds 60–90%, 1 seed > 90%. Use sterilised straw to cover the pots and maintain humidity. Water once a day with 3–4 litres/m2 to keep seeds moist after sowing.

Sowing into beds....

9. (pp. 5-7)

Early and sustained weed management and fertiliser treatment, and occasional watering in are all key elements in the successful establishment of a Erythrophloeum fordii plantation. The appropriate stocking rate (planting density) must be established in order to promote optimum growth rates and efficient plantation management.

Weed control is necessary to reduce the competition for water and nutrients between trees and weeds. Competition from weeds severely decreases early tree performance, and weed growth can be prolific in subtropical and tropical regions. Weed control before planting and for at least 12 months after should be considered essential for successful plantation establishment. A...

10. (pp. 7-8)

Erythrophloeum fordii samples were collected from 45 plots in smallholder plantations in Phu Tho Province, Vietnam, representing various age classes (2, 3, 5, 6, 13, 16 and 23 years). In this study, Michailow’s growth function was used to estimate the diameter and height of the stand.

$H=a*\exp (\frac{-b}{\textrm{age}})\; \; \; \; D=a*\exp (\frac{-b}{\textrm{age}})$

Table 1 presents growth in diameter and height of samples from 45 Erythrophloeum fordii plots.

The annual growth in diameter and height from 1 to 23 years of age is nearly identical. These plantations were evaluated to determine the mean annual increases. They achieved a minimumincrease in diameter of 0.6 cm and height...

11. (pp. 8-9)
12. (pp. 10-10)