Ascension : Conservation Weekly
Submitted by The Islander (Conservation Office) 11.09.2008 (Article Archived on 25.09.2008)
In recent months heavy rains have encouraged the growth of grasses on Ascension.
(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)…
Enneapogon cenchroides, close-up -
Andrew Darlow
BY Phil Lambdon
Enneapogon cenchroides
Soft feather pappus grass (N. American name)
This is a widespread grass in tropical Africa. It occurs from Sudan down to the Cape Region, and also throughout the Arabian Peninsula into India. In these regions it normally occurs in similar situations to Ascension – on dry, rocky areas with poor soils. The seeds have a remarkable ability to lie dormant for several years, but germinate rapidly in response to heavy rains. It seems that some plants normally germinate each winter, but there may be a massive flush once every 8-15 years. It may form tumble-weed, which perhaps helps to spread the seed.
Enneapogon can be recognized by its bushy flowering heads. Each individual flower has a short hair-like projection (the awn) at the tip, but this is barely noticeable and the flowers drop-out quite quickly leaving two empty scales (glumes).
Enneapogon cenchroides, flush of growth – Andrew Darlow
It remains a mystery how long the grass has been on Ascension. The first record on the island was in 1917 by O. Stapf, who thought that it had recently arrived on the feathers of wideawakes. However, sea-living birds seem an unlikely means of transport, and since Enneapogon almost dies-out in poor years, it is quite possible that it was missed by earlier botanists and may have been around for much longer.
Note: Volunteers are still needed to assist with the botanical survey being conducted by the EU Invasive Species Project. If you are interested in the project, please contact the Conservation Department at x6359.
Request: Please contact the Conservation Dept. if you are planning the Dew Pond Run this year. Thank you!
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