Capturing the Diversity – Stedson’s Spurge

This ridge was proving to be a marker for nesting success.  Over the last few years, there seemed to have been a expansion of nesting from the Letterbox area itself up this slope  We recorded the data and moved on.  Stedson started to get more interested and wanted to show me a little gut in the ridge.  Running steeply downhill, the gut cut a gully only a few feet deep, and at first sight was scouring away at the volcanic rubble here, but through a series of terraced steps some of the smaller washed material had been trapped.  This thin grey gritty soil had become the habitat for tiny plants, more or less the only greenery around this area.  This was a type of Euphorbia, or spurge, endemic to Ascension Island.  Stedson had been instrumental in both identifying it and building up its population.  He took out some polythene bags and collected the tiny seeds.  As well as a small number of very small natural populations over this part of the island, he was trying to find where to introduce them elsewhere.  Probably the only native which ever managed to colonise the dry lowlands of Ascension where there was hardly any soil or water and oodles of scorching sunlight and drying winds, this was a tough little plant.  Other more widely spread spurges do exist on Ascension Island, but this one has a gorgeous reddy stem, with the little bulbous leaves, storing away all that precious water it needs to survive within a thick plastic like skin.  And the tiny flowers are so pretty with their little white heads.  But all on a minute scale and unless there was a large carpet colony of them, most people would never even notice they were there.

The Ascension Spurge – logging the location

The hostile environment in which spurge can spread

Stedson collecting spurge seeds

Stedson was different.  He had an eye for spotting individual plants in amongst others or the empty terrain like here, and he had built up his own knowledge of their environmental niches, so much so he could more or less predict where you might find one of his precious endemics. I remember a tour he took around one of the uppermost paths on Green Mountain, Elliot’s.  While we were happy to see the mix of vegetation at different stages of the trail, he could spot the tiny collections of endemic ferns in a rockface or on a ledge.