Pinus patula (Patula Pine)

Scientific name

Pinus patula Schldl. et Cham.

Synonyms

Pinus oocarpa var. ochoterenai Martinez; Pinus patula var. longipedunculata Loock ex. Martinez; Pinus patula var. zebrina Milano; Pinus subpatula Roezl. ex. Gord.

Common names

Patula pine, jelecote pine, Mexican weeping pine, spreading-leaved pine, tecote pine

Family

Pinaceae

Origin

Native to Central America

Naturalised distribution (global)

Locations within which Pinus patula is naturalised include parts of Australia, New Zealand, Argentina, Brazil, Madagascar, Southeast Asia, and southern and eastern Africa.

Introduced, naturalised or invasive in East Africa

Pinus patula is invasive in parts of Tanzania (Lyons and Miller 1999), Kenya and Uganda (A.B.R. Witt pers. obs.) .

Habitat

Pinus patula is planted in production forests but can spread to forest gaps, grassland and shrubland.

Description

Pinus patula is a coniferous tree which grows to a height of 30 m or more and attains a diameter at breast height (1.3 m) of up to 1.2 m. The trunk is straight and cylindrical, sometimes forked, producing 2 or more stems. When grown at wide spacing, the crown tends to spread and is "see-through". The crown may also be rounded or spire-like. Young bark is characteristically a reddish-orange colour and is scaly. The mature bark is grey-brown and vertically ridged.

Leaves (needles) are grey-green - yellow-green, in clusters of needles (fascicles) of 3, occasionally 4, rarely 5; slender, 15-25 cm long drooping, pale green to yellowish-green colour, the margins finely toothed.

The pine cones are reddish-brown, conical in shape and borne on short stalks. They borne singly or in small clusters. The cones are hard, flat or slightly raised cone scales.. Seeds are dark brown to almost black, very small, about 5 mm long, with a pale brown wing about 17 mm long, slightly thickened at the base where it joins the seed.

Reproduction and dispersal

Pinus patula reproduces through small, light wind-dispersed seeds.

Economic and other uses

Pinus patula is a major forestry tree and can be used for board manufacturing, and furniture as well as for paper and pulp production, furniture, etc. It can be tapped for gum and resin. It thrives in semi-tropical environments, especially at higher altitudes.

Environmental and other impacts

Pinus patula can rapidly invade grassland and shrubland (usually originating in production plantings) where they can compete with native plants, affect fire and hydrological regimes. In South Africa invasive pines have significantly reduced water availability and have had a very negative impact on plants in the fynbos, an area of global biodiversity significance.

Pinus patula has been listed as a Category 2 invader in South Africa (invaders with certain qualities, e.g. commercial use or for woodlots, animal fodder, soil stabilisation, etc. These plants are allowed in certain areas under controlled conditions).

Management

The precise management measures adopted for any plant invasion will depend upon factors such as the terrain, the cost and availability of labour, the severity of the infestation and the presence of other invasive species. Some components of an integrated management approach are introduced below.

The best form of invasive species management is prevention. If prevention is no longer possible, it is best to treat the weed infestations when they are small to prevent them from establishing (early detection and rapid response). Controlling the weed before it seeds will reduce future problems. Control is generally best applied to the least infested areas before dense infestations are tackled. Consistent follow-up work is required for sustainable management.

Pinus patula will not re-grow if cut low to the ground and all green foliage is removed so physical control can be effective. Trees can be killed standing by ring barking, frilling (making deep cuts at regular intervals around the base of the tree and applying herbicide into the cuts) and tree injection. When using any herbicide always read the label first and follow all instructions and safety requirements. If in doubt consult an expert.

There are a number of potential pests and pathogens that could be used as biological control agents but they are generalists and so are not suitable agents (A.B.R. Witt pers. comm.).

Legislation

Not listed as a noxious weed by the state or governments in Kenya, Tanzania and Uganda.

References

Bekele-Tesemma, A., Birnie, A. and Tegnas, B. (1993). Useful trees and shrubs for Ethiopia. Regional Soil Conservation Unit (RSCU), Swedish International Development Authority (SIDA).

Global Invasive Species Database online data sheet. Pinus spp. www.issg.org/database. Accessed March 2011.

Henderson, L. (2001).  Alien weeds and invasive plants. A complete guide to declared weeds and invaders in South Africa.  Plant Protection Research Institute Handbook No. 12, 300pp. PPR, ARC South Africa.

Katende, A.B., Birnie, A. and Tegnas, B. (1995). Useful trees and shrubs for Uganda. Identification, Propagation and Management for Agricultural and Pastoral Communities. Regional Soil Conservation Unit (RSCU), Swedish International Development Authority (SIDA).

Lyons, E.E., Miller, S.E. (eds)1999 Invasive Species in Eastern Africa: Proceedings of a Workshop held at ICIPE, July 5-6, 1999.

Editors

Agnes Lusweti, National Museums of Kenya; Emily Wabuyele, National Museums of Kenya, Paul Ssegawa, Makerere University; John Mauremootoo, BioNET-INTERNATIONAL Secretariat - UK.

Acknowledgments

This fact sheet is adapted from The Environmental Weeds of Australia by Sheldon Navie and Steve Adkins, Centre for Biological Information Technology, University of Queensland. We recognise the support from the National Museums of Kenya, Tropical Pesticides Research Institute (TPRI) - Tanzania and Makerere University, Uganda. This activity was undertaken as part of the BioNET-EAFRINET UVIMA Project (Taxonomy for Development in East Africa).

Contact

BioNET-EAFRINET Regional Coordinator: eafrinet@africaonline.co.ke