Common name:Algerian ash
Scientific name:Fraxinus angustifolia
Alternative common names:
Ash, desert ash, narrow leaf ash.
The Algerian ash is a medium-sized, deciduous tree growing to 20–30m tall with a trunk up to 1.5m in diameter. It is not commonly planted anymore, however large numbers of adult trees can still be seen growing in suburban areas. The flowers are produced in inflorescences, which can be male, hermaphrodite or mixed male and hermaphrodite. Flowering occurs in early spring.
Where does this species come from?Central and Southern Europe, Northwest Africa and Southwest Asia.
What is its invasive status in South Africa?NEMBA Category 3.
Where in South Africa is it a problem?Gauteng, KwaZulu-Natal, Free State, Eastern Cape and Western Cape.
How does it spread?It reproduces by seed and also spreads laterally via root suckers. Pieces of stem and branches can also take root when they come into contact with moist soil (a process known as layering). The winged seeds are mainly dispersed by wind and in dumped garden waste. It is also thought to be spread by animals ( birds, foxes).
Why is it a problem?The Algerian ash outcompetes indigenous plants for moisture, light and nutrients, and can take over the vegetation in natural areas. Over time it forms dense monocultures, spreading via suckers and preventing the regeneration of indigenous species. It also invades roadsides and stream banks in cool regions.
What does it look like?Leaves: Compound leaves, 14-25cm long, have 5-13 elongated leaflets with toothed margins. Flowers: Inconspicuous flowers are borne in small branched clusters and do not have any sepals or petals. Fruit/seeds: Winged fruit, 3-5cm long, narrowly oval in shape and often slightly twisted.
Does the plant have any uses?It is cultivated as an ornamental shade and street tree.