It is unclear whether the current western bias of the species reflects the original distribution (i.e., that prevailing before humans settled St Helena in the 1600s) although it is likely that Dwarf Jellico was more widespread along the crags of the Central Ridge at one time. Establishment of extensive New Zealand Flax plantations over many of the steepest slopes in the first half of the 20th Century would undoubtedly have removed much potentially suitable habitat. However, there were scant records even before this. Deforestation for timber, and removal of native cloud forest habitat to make way for pasture, may have reduced the population to fragments before botanical records were made on the island.
Overall, the limited numbers of plants found in the Diana’s Peak area, and their advanced state of fragmentation, make it highly likely that the species will eventually be lost from the eastern Central Ridge in coming decades. Current numbers clearly represent only a fraction of the 800 seedlings which were introduced in 1996 (Cairns-Wicks, 2003). The main threats appear to stem from heavy infestations of non-native plants in suitable habitat. The steep western escarpments of Diana’s Peak have been largely overgrown by tall invasive species such as Whiteweed (Austroeupatorium inulifolium (Kunth) R.M.King & H.Rob.), Bilberrry Tree (Solanum mauritianum Scop.), Smokebush Buddleja (Buddleja madagascariensis Lam.) and New Zealand Flax. In addition to this hazard, there is a strong suspicion that the species has hybridized with the much larger Jellico, which is still reasonably widespread in the eastern Peaks. Possible hybrids were reported in 2003 (Cairns-Wicks 2003) and a number of dubious individuals still exist around Taylor’s Flat.
At present, there are fewer immediate threats facing the western strongholds, though some of the Red Rock fragments are small and could be overgrown by dense swards of pasture grasses which appear to be advancing on the crags. Fortunately, the cliffs of High Peaks remain relatively free of invasive infestations. In the future however, the situation could be transformed for the worse if problematic weeds were to gain a foothold in the core habitats. There is a pressing danger of this, since two very aggressive non-natives, which are already a major nuisance elsewhere in the cloud forest zone, have now advanced their range to within very close proximity. Small Fuschia (Fuchsia coccinea Curt.) and Pheasant-Tail Fern (Nephrolepis cordifolia (L.) C.Presl) both form very extensive, smothering growths, and at least in the former case, seedlings have already been detected growing on remote parts of High Peak face.
The hybridization issue also affects the western population stronghold. An extensive area of plants which appear completely intermediate between the parents have been present at High Peak since the 1950s (Kerr 1970). These are not known to have spread outside a single colony, but the hybrid form is clearly capable of reproducing effectively and should they succeed in back-crossing to plants at other localities, there is a risk that the integrity of the population could be compromised.