Agathis philippinensis

Agathis philippinensis
Scientific classification
Kingdom: Plantae
Division: Pinophyta
Class: Pinopsida
Order: Pinales
Family: Araucariaceae
Genus: Agathis
Species: A. philippinensis
Binomial name
Agathis philippinensis
Warb.

Agathis philippinensis (in Tagalog: Almasiga or Dayungon) is a species of large Agathis tree native to the Philippines, Sulawesi and Halmahera, where it occurs in upland tropical rainforest at 450-2,200 m altitude, rarely as low as 250 m in northern Luzon.

The Agathis is a very ancient family of coniferous trees. The group achieved its maximum diversity in the Jurassic and Cretaceous periods, when it was distributed almost worldwide. At the end of the Cretaceous, when the non-avian dinosaurs became extinct, so did most of the Araucariaceae in the Northern Hemisphere. At least one genus, Agathis, survived into the Eocene.

In the Philippines, the almasiga belongs to very ancient plants alongside ferns and tree ferns, cycas, horsetails, spikemosses and mosses.

Description

It is a large coniferous evergreen tree growing up to 65m tall with smooth, grey coloured bark. The leaves are oval, 4–6 cm long and 1.5–2 cm broad on adult trees, slightly larger, up to 7 cm long and 3 cm broad, on young trees. The seed cones are squat ovoid, 7–9 cm long and 12 cm diameter, containing numerous spirally arranged scales 28–32 mm long and 35–45 mm broad, each scale bearing a single winged seed. The pollen cones are 25–45 mm long and 10–11 mm broad. It is the northernmost species of Agathis, occurring north to 19°N on the Philippine Calayan islands north of Luzon.

Uses

The tree is commonly used throughout the Philippines, Melanesia and Australasia as an enrichment crop. Despite being limited by altitude constraints it is tolerant of most different soil densities, though it requires good drainage and prefers acidic soils. It has a special tolerance for shallow, infertile soils. The tree is therefore used to support areas which do not experience adequate crop growth and is also planted inside of existing plantations to replace existing trees.

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