Common name Desert Ash
Botanical name Fraxinus angustifolia
Family Oleaceae
Natural range Europe
Mature height 10-12m
Form Broad spreading
Likes Dispersing seeds
Dislikes Root disturbance
Where to plant Nowhere!
Known for Spreading seeds everywhere
Have you heard of the Desert Ash (Fraxinus angustifolia)? It’s a part of the Oleaceae family, a European native reaching a mature height between 10-12m. Recognized by its broad spreading form, it’s a notorious seeder that doesn’t take kindly to root disturbance.
The Origin of Desert Ash’s Popularity in Australia
Initially, the Desert Ash garnered popularity across Australia, particularly in the southern states, for lining roadsides and enhancing gardens. With its robust nature and splendid autumn colours, it seemed like an ideal choice. However, as the trees matured, a major issue surfaced.
Why this Ash Became a Problem
Mature Desert Ashes have a relentless propensity for dispersing seeds. So much so, that they’ve earned a reputation for hyper-fertility, leading to the sprouting of seedlings in unwanted areas.
Impact of Fraxinus angustifolia Invasion
When the Desert Ash takes over bushland, grasslands, or stream banks, it outcompetes native plants for sunlight, moisture, and nutrients. The result? A vulnerable native ecosystem battling an invasive foreigner.
It’s in Victoria’s national parks where this tree is commonly identified as an intrusive weed. Oddly enough, these culprits are often found near car parks and along trails. Thanks to wind-pollinated flowers and winged seeds or ‘samaras’, their widespread dispersal is facilitated. Moreover, the presence of root suckers and seeds carried away by water allows this species to invade creeks and wetlands.
The Current Stance on This Fraxinus sp.
Today, the Desert Ash’s impacts have been duly noted and it’s now classified as an environmental weed in Victoria, South Australia, the Australian Capital Territory, and southern New South Wales. Interestingly, in many instances, you can even remove these trees from private gardens without needing a council permit.
Environmentally Friendly Alternatives
For those still wanting an Ash tree, there are safe alternatives. Sterile variants of Fraxinus exist which won’t pose the same threats due to their inability to produce seeds. Two such options are the Claret Ash (Fraxinus angustifolia ‘Raywoodii’) and the Golden Ash (Fraxinus excelsior), both offering spectacular autumnal colours.
Interesting Facts:
- Despite being classified as a weed, the Desert Ash is still used in some places for soil erosion control due to its extensive root system.
- The Desert Ash can live for over 200 years!
Further Reading Links: