Thursday, February 9, 2017

Dacryodes edulis

Dacryodes edulis or safou is a fruit tree native to Africa, sometimes called Atanga (Gabon), Ube (Nigeria), African pear, bush pear,  African plum, Nsafu, bush butter tree, or butterfruit.

Dacryodes edulis is an evergreen tree attaining a height of 18–40 m in the forest but not exceeding 12 m in plantations. It has a relatively short trunk and a deep, dense crown.
The bark is pale gray and rough with droplets of resin.
The leaves are a compound with 5-8 pairs of leaflets. The upper surface of the leaves is glossy.
The flowers are yellow and about 5 mm across. They are arranged in a large inflorescence. The tree flowers at the beginning of the rainy season and bears fruits during 2 to 5 months after flowering.
The fruit is an ellipsoidal drupe which varies in length from 4 to 12 cm. The skin of the fruit is dark blue or violet, whereas the flesh is pale to light green.
There are two variants of Dacryodes edulis: edulis and parvicarpa. The fruit of edulis is larger and the tree has stout, ascending branches. parvicarpa has smaller fruit and slender, drooping branches.

Habitat and Range
The preferential habitat of D. edulis is a shady, humid tropical forest. However, it adapts well to variations in soil type, humidity, temperature and day length.
The natural range extends from Angola in the South, Nigeria and Sierra Leone in the West and Uganda in the East. It is also cultivated in Malaysia, apparently.

The main use of D. edulis is its fruit, which can be eaten either raw, cooked in salt water or roasted. Cooked flesh of the fruit has a texture similar to butter. The pulp contains 48% oil and a plantation can produce 7-8 tons of oil per hectare. The fat content of this fruit is much higher compared to fruits such as apple, guava, and pawpaw.  It is also rich in vitamins. The kernel can be used as fodder for sheep or goats. The flowers are useful in apiculture. Shade tolerant traditional crops, such as Xanthosoma sagittifolium and taro can be co-cultivated with D. edulis.

The wood of D. edulis is elastic, greyish-white to pinkish. The wood has general use for tool handles, and occasionally for mortars, and is suitable for carpentry.

The seed of Dacryodes edulis is rich in different proportion of carbohydrates, proteins, crude fibres, appreciable amounts of potassium, calcium, magnessium and phosphorus. It is also rich in essential amino acids such as Lysine, Phenylalanine, Leucine, Isoleucine. It contain a considerable amount of fatty acis such as palmitic acis, oleic acis and Linoleic acids.   Physicochemical analysis suggested that the seed have valuable functional attributes of industrial interest

The tree is also a source of many herbal medicines. It has long been used in the traditional medicine of some African countries to treat various ailments such as wound, skin diseases, dysentery and fever. The extracts and secondary metabolites have been found to show biological activities such as antimicrobial, antioxidant  and anti sickle-cell disease.[citation needed] A wide range of chemical constituents such as terpenes, flavonoids, tannins, alkaloids and saponins have been isolated from the plant.

The resin is sometimes burnt for lighting or used as a glue.

The tree is used as an ornamental plant and is known to improve soil quality by providing large quantities of biomass.

Tuesday, January 24, 2017

Seremban : Tembusu Chopping Boards

The Tembusu wood is a very hard wood, normally used to make chopping boards.  The wood is resistant to termites and weevils, thus can last very long, some over 100 years.

Tembusu is Fagraea fragrans, a large slow-growing evergreen tree in the family Gentianaceae.  

Sunday, January 22, 2017

Garcinia parvifolia - kundong

Kundong ( Sarawak Iban ) is Garcinia parvifolia, a member of the Clusiaceae family.  The specific name, parvifolia, refers to its small leaf; while Garcinia is named after a French botanist Laurent Garcin.

Native to the Malesia ecozone, the fruit is highly esteemed in Sarawak.  Naturally grown in primary and secondary rainforest, it can be propagated by seeds.  The tree is sometimes planted as ornamental in parks and gardens.

The fruit is round to elliptic, up to 40mm in diameter.  Brilliant red in colour, with 1-8 seeds covered in white, succulent, sweet pulp. 

The fruit is consumed raw or cooked.  It has a juicy, white pulp with a delicious sweet-tart flavor, almost similar of its cousin mangosteen ( Garcinia mangostana ). 

Monday, January 9, 2017

Landscape : Curbing the Curbs 3

If the main role of road curbs are to keep vehicles on the road, and preventing them off the green area and especially walkway, then it can be easily replaced with guardrails. 

In Malaysian environment, weather is a nuisance. There are times when it rains so heavily, causing flash floods ; and there are also times when there is not a single drop of rain for weeks. 

Cambered asphaltic concrete road (A) allows fast flow of water off the road surface.  If the surface water are directed straight to the drain (C), there will be minimal water seepage through the green area.

However, if the green areas are designed conclave to trap water (B), not too much of course, just enough for some water to seep into the ground and thus more water available for trees and shrubs. 

The water from watering tank during dry spell too will be more effectively seep into the soil, mineral soils especially. In addition, it also trap the fertilizer from being easily washed away.

Sunday, July 31, 2016

Darwin : Phototropism

Darwin was fascinated by the effects of light on plant growth, as was his son Francis. In his final book, The Power of Movement in Plants, Darwin wrote: ‘There are extremely few [plants], of which some part … does not bend towards lateral light.’ Or in less verbose modern English: almost all plants bend towards the light.

In a very simple experiment, published in 1880, Darwin and his son showed that this bending was due to some inherent sensitivity to move towards the light.

For their experiment, Darwin and his son, Francis, grew a pot of canary grass (Phalaris canariensis) in a totally dark room for several days. Then they lit a very small gas lamp twelve feet (3.5 metres) from the pot and kept it so dim that they ‘could not see the seedlings themselves, nor see a pencil line on paper.’ But after only three hours, the plants had obviously curved towards the dim light. The curving always occurred at the same part of the young plant, an inch or so below the tip.

This led them to question which part of the plant saw the light. The Darwins carried out what has become a classic experiment in botany.  They hypothesized that the ‘eyes’ of the plant were found at the seedling tip and not at the part of the seedling that bends.

They checked phototropism in five different seedlings, illustrated by the following diagram:

a. The first seedling was untreated and shows that the conditions of the experiment are conducive to phototropism.
b. The second had its tip pruned off.
c. The third had its tip covered with a lightproof cap.
d. The fourth had its tip covered with a clear glass cap.
e. The fifth had its middle section covered by a lightproof tube.

They carried out the experiment on these seedlings in the same conditions as their initial experiment, and of course the untreated seedling bent towards the light.  Similarly, the seedling with the lightproof tube around its middle bent towards the light. If they removed the tip of a seedling, however, or covered it with a lightproof cap, it went blind and couldn’t bend towards the light. Then they witnessed the behaviour of the plant in scenario four (d): this seedling continued to bend towards the light even though it had a cap on its tip.  The difference here was that the cap was clear. The Darwins realized that the glass still allowed the light to shine onto the tip of the plant.

In this experiment, the Darwins proved that phototropism is the result of light hitting the tip of a plant’s shoot, which sees the light and transfers this information to the plant’s midsection to tell it to bend in that direction.

Extracted from What a Plant Knows – A Field Guide To The Senses Of Your Garden And Beyond, 2012, Daniel Chamovitz

Sunday, July 17, 2016

Buluh Lemang - Schizotachyum brachycladum

Lemang is a traditional Malay food made of glutinous rice, coconut milk and salt, cooked in a hollowed lemang bamboo, lined with banana leaves.

The lemang bamboo ( buluh lemang ) ( Schizotachyum brachycladum ) is used for cooking lemang because of its unique properties :

1. Availabililty – Not Too Difficult To Find
The bamboo is evergreen plant native to tropical Asia, abundance all over lowland secondary forest.  It produces several new stems annually, each stems grow to their maximum heights in their first year of growth.  Propagation is common, usually by rhizome and clum cuttings.

It has been used in Borneo, Java, Bali, Malesia, Cochinchina, etc for construction, handicraft, container for water and cooking, etc.

2. Length – Not Too Long, Not Too Short
Buluh lemang’s clum are erect and straight, about 10-15m in length, 6-8cm in diameter. With approximately 7-10 hollow internodes, each 20-50cm in length, buluh lemang is suitable as a vessel for cooking.

3. Thickness – Not Too Thick
The bamboo’s internode wall is thin, about 3-5mm think, comparable to other species of bamboo.  The thin wall is easy to cut through, shortened the cooking time and uses less firewood.