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Following the rediscovery of the Horse Pasture tree, seed was collected and several daughters were propagated (Cairns-Wicks 2009). By 2009 these had dwindled to a single individual located at Pouncey’s, which was in poor condition. Further propagation attempts had been unsuccessful because, although germination was found to be moderately good, all saplings proved to be of hybrid origin. The tree had crossed with False Gumwoods (C. spurium (G.Forst.) DC.), growing at a nearby nursery, to produce fertile offspring.
In order to rectify the problem, in 2010 a cage of insect-proof mesh was erected around the remaining Bastard Gumwood to exclude pollinators, and an intensive programme of hand-pollination and seed collection was undertaken by a collaboration of Government staff, the St Helena National Trust and local volunteers. Large quantities of seed were sown, and despite the low germination rate, over 100 saplings were reared in the first year.
Whilst the emergency rescue programme was being implemented, the wild tree at Botley’s was discovered. The presence of a second individual offered the possibility of increasing genetic diversity and overcoming the self-incompatibility barrier (assuming that the two plants belonged to different compatibility groups). A small amount of pollen was obtained from Botley’s in the first season and crossed to a few inflorescences at Pouncey’s, but the seed was accidentally mixed during collection and thus it is not know whether viability was enhanced.
Subsequently, the intensive propagation work has continued as a result of two restoration projects (funded by JNCC and OTEP). Seed from both parents have now been cultivated, and saplings reared together at three locations. Those transplanted to High Hill have not fared particularly well, but over thirty mature trees are now growing at Drummond’s Point. These have flowered and produced seed. The extent of cross pollination between the genotypes is not clear, but the germination rate has increased by at least 1000% in these second generation plants (pers. comm., A. Darlow 2014). In March 2015 two self sown seedlings were discovered beneath these second generation plants. A third group of over 100 plants has been established in the Agriculture and Natural Resources complex at Scotland.
The success of the recovery work to date has provided some hope of re-establishing a stable Bastard Gumwood population in the future. However, while numbers are still very low, the cultivated sites are very vulnerable and plants remain in need of regular attention as they are subject to heavy pest outbreaks. Ants are very abundant at Drummond’s Point, and actively spread sap-sucking pests between hosts in order to feed on their honeydew. Furthermore, the work will soon have to be taken forward without dedicated funding. It is hoped that staff of St Helena Government’s Environmental Conservation Section will maintain a more limited maintenance programme in the short-term.
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