Jointfir, Melinjo, Meninjau
Gnetum gnemon

Family: Gnetaceae

What it is like

Gnetum gnemon is an evergreen Tree growing to 15 m (49ft) by 5 m (16ft) at a slow rate. See above for USDA hardiness. It is hardy to UK zone 10. The flowers are pollinated by Moths. The plant is not self-fertile. Suitable for: medium (loamy) and heavy (clay) soils. Suitable pH: mildly acid, neutral and basic (mildly alkaline) soils and can grow in saline soils. It can grow in full shade (deep woodland) semi-shade (light woodland) or no shade. It prefers moist soil and can tolerate drought.

Height (m): 15

Where it is found

Occasional in lowland ridges and mature fallow forest. Commonly found in secondary humid evergreen dipterocarp forests.

E. Asia - China, India, Bangladesh, Myanmar, Thailand, Cambodia, Vietnam, Malaysia, Indonesia, Philippines, New Guinea to Fiji.

Conservation Status: Status: Least Concern

Countries/locations it is found in

Bangladesh; Cambodia; China; Fiji; India; Indonesia; Malaysia; Myanmar; Papua New Guinea; Philippines; Solomon Islands; Thailand; Vanuatu; Viet Nam

How it is used

Food

Rating: 3

Young leaves - raw or cooked. Steamed and eaten as a potherb. Seed - usually cooked. The nutritious seeds are boiled and eaten as a snack like peanuts. Eaten as a dessert nut. The seeds have a slight bitterness. A fine flour can be obtained from the ground up seed - it is used for making thin crackers, known as 'emping', which are fried in coconut oil and eaten with rice etc. The seed is 2 - 4cm long, turning scarlet to red-tinged orange when ripe. The fruits and inflorescences are added to soups. Peel of the ripe fruit is dried and used in soups. Somewhat tasteless. The sap from the stem is drinkable.

Sap: usually of trees and usually but not always used as a drink.

Seed: includes nuts, cereals, peas and beans.

Condiment: the various plants that are used as flavourings, either as herbs, spices or condiments.

Drink: not including plant saps, tea or coffee substitutes.

Medicine

Rating: 1

The leaf sap is used medicinally to cure an eye complication.

Ophthalmic: Treats eye complaints.

Other

Rating: 3

Design: Shade garden; Accent tree; Specimen; Fruiting tree; Street tree; Botanical collection; Conservatory. Agroforestry Uses: It is possible to use this tree for dryland rehabilitation and reforestation. It can survive annual rainfall of 750 - 1,000mm. In Papua New Guinea this species can be found growing alongside breadfruit (Artocarpus spp.), Pandanus conoideus and other food and fibre species. It is intercropped with several species like Arctocarpus camansi, Pandanus spp., Durio spp., Nephelium lappaceum (rambutan) and Parkia sp. Other Uses The bast fibres provide durable cordage for fishing nets, lines, string bags and other durable tools. A potential economic use of this plant is the utilisation of its bark in rope making. Wood smoke and topical applications reduced biting of human volunteers by the anopheline mosquitoes by 79% and 51%, respectively. Enzyme inhibition prevents insect predation of foliage. The wood is used for pulp, house construction, paper and boxes. Fruit for wild birds and bats.

Containers: Plants, such as gourds, that can be used as containers. Does not include baskets or containers made from wood.

Fibre: Used for making cloth, rope, paper etc.

Insecticide: Kills insects.

Paper: Related to the entry for Fibre, these plants have been specifically mentioned for paper making.

Repellent: Plants that are said to deter but not necessarily kill various mammals, birds, insects etc.

String: Plants that can be used for string or can be easily made into a string. See also Fibre. Plants for ropes may be included.

Wood: A list of the trees and shrubs that are noted for having useful wood.

Industrial Crop: Fiber: Clothing, rugs, sheets, blankets etc. Currently, almost none of our fiber are produced from perennial crops but could be!

Management: Standard: Plants grow to their standard height. Harvest fruit, seeds, or other products. Non-Destructive management systems.

Regional Crop: These crops have been domesticated and cultivated regionally but have not been adopted elsewhere and are typically not traded globally, Examples in this broad category include perennial cottons and many nuts and staple fruits.

Staple Crop: Balanced carb: (0-15 percent protein, 0-15 percent oil, with at least one over 5 percent). The carbohydrates are from either starch or sugar. Annuals include maize, wheat, rice, and potato. Perennials include chestnuts, carob, perennial fruits, nuts, cereals, pseudocereals, woody pods, and acorns.

Industrial Crop: Fiber: Clothing, rugs, sheets, blankets etc. Currently, almost none of our fiber are produced from perennial crops but could be!

Management: Standard: Plants grow to their standard height. Harvest fruit, seeds, or other products. Non-Destructive management systems.

Carbon Farming: Plants that can be a critical part of the solution to climate problems. The Carbon Farming Solution - Eric Toensmeier.

Food Forest: Plants for Edible Forest Gardens and Food Forests.

How it is grown

Grows best in humid tropical areas at elevations up to 1,200 metres. Very tolerant of different levels of rainfall, succeeding with a mean annual rainfall in the range 750 - 5,000mm. Prefers a position in semi shade in a humus-rich, moist soil. Tolerates full sun. Succeeds in heavy shade. Succeeds in a wide range of well-drained soils, preferably slightly acid to neutral, but tolerating calcareous rocks. Tolerant of low fertility soils. Able to tolerate drought for some months, assuming some soil moisture retention or irrigation during dry season. Tolerant of strong winds, so long as they do not carry salt spray. Plants are deeply rooted with a strong tap root system. The plant exists in several varieties, in particular there is the tree form (var. Gnemon) and three shrub forms (vars., brunonianum, griffithii and tenerum) The cultivated trees belong to Gnetum gnemon var. Gnemon and are larger, with larger fruits. Melinjo has the ability to improve nitrogen levels in the soil due to its mycorrhizal associations with the ectomycorrhizal fungus Scleroderma sinnamariense. In experimental conditions, mycorrhizal inoculation appears to enhance seedling growth under shaded conditions in acidic soils. A dioecious plant, male and female forms need to be grown if seed is required. A coupled process of double fertilization and post-fertilization endosperm formation occurs in the genus Gnetum. However the product of the second fertilization event in Gnetum is diploid and expresses the developmental programme of an embryo. In G. Gnemon, egg cells are not formed and maternal provisioning of the embryo-nourishing female gametophyte takes place entirely after fertilization. The lack of differentiated egg cells in G. Gnemon is unparalleled among land plants, the biological significance of double fertilization that does not form endosperm, in Gnetum, is currently unknown. This process may be biologically neutral. Seeds produced three times yearly in Indonesia, March-April, June-July and September-October. The strobili are visited by nectar-seeking moths of Pyralidae and Geometridae. The sticky pollen of Gnetum attaches on proboscides and antennae of these moths. Lack of showy petals, an apparent disadvantage in entomophily is compensated for by floral fragrancy

Propagating it: Seed - best sown in situ. Daily watering of the sand and seed mixture will hasten germination, possibly to three months. Without a pre-germination treatment, germination may be 1-2% in 6 months and may reach 100% in 12 months. Air layering. Short cuttings, taken beneath a node. Budding. Grafting.

Best place to grow:

Habit: Tree

Hardiness: 10-12

Growth: Slow

Soil: Medium, heavy (clay)

Shade: Full shade, semi-shade, no shade

Moisture: Moist

Things to keep in mind

Its other names

Local names

Common names include gnemon, melinjo, belinjo, kuliat/culiat, padi oats, paddy oats, Belinjau, Meninjau, Bago, Gnemon Tree, Maninjau, Minjau, Songkok, Spanish Joint Fir

Synonyms

Gnetum vinosum Elmer.

Jointfir, Melinjo, Meninjau Gnetum gnemon