Ascension : Conservation Weekly - ASCENSION’S GRASSES (PART TWO):
Submitted by The Islander (Conservation Office) 18.09.2008 (Article Archived on 02.10.2008)
A very widespread species throughout the tropics, occurring in North and South America, southern Europe, Africa and Asia as far as China.
(Note: In recent months heavy rains have encouraged the growth of grasses on Ascension. Our landscape was transformed from barren rocky expanses to undulating fields of gold. Phil Lambdon of the EU Invasive Species Project has prepared some background information about theses grasses which have made such an expansive (and sudden) appearance)…
BY Phil Lambdon
Aristida adscensionis
Common needle grass or six-week triple-awn grass (N. American names).
Aristida adscenAristida adscensionis, close up - Andrew Darlow scensio
A very widespread species throughout the tropics, occurring in North and South America, southern Europe, Africa and Asia as far as China. It prefers hot, dry habitats, often where the soil is loose or disturbed. It is usually a very short-lived annual grass but can survive for 1-2 years as a small tussock. In some places it is used for cattle grazing, but generally only when young as the sharp seeds can stick in the mouths of livestock.
When not flowering, Aristida and Enneapogon are very difficult to distinguish, but flowering plants are easily separated. Aristida flowers have three long hair-like awns at the tip, which become bent outwards as they age and are very conspicuous.
Aristida adscensionis, young plant - Andrew Darlow
Aristida occurs across Ascension Island, but is most common on dry flats and coastal cliff tops in the east, where it can be very abundant. It was formerly more common higher on the slopes of Green Mountain, but has now been out-competed by greasy grass (Melinis minutiflora). Despite its cosmopolitan range, this species was first discovered and identified on Ascension Island by James Cunninghame in 1698 and was originally thought to occur nowhere else, which is why the island is remembered in its scientific name.
NOTICE ABOUT RABBITS: The AIG Conservation Dept. undertakes very limited trapping for rabbits in certain areas within Green Mountain National Park. Our remit is to protect our endangered plants which are found on Ascension and no where else in the world. In some cases, this involves removing invasive species (such as rabbits) which threaten the survival of these special endemic plants. The trapping is done humanely and only to protect the endangered plants. Lately, several of the traps have been stolen. Please let this be a reminder that the traps should not be removed or disturbed in any way. If you have any questions about rabbits or rabbit trapping, please feel free to ring the Conservation Dept. x6359.
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