Meet the scientist
Principal Entomologist at the Royal Horticultural Society
Entomologist Andrew Salisbury on discovering a webspinner colony at the RHS Garden Wisley
When Andrew Salisbury first joined the Royal Horticultural Society (RHS) as a research assistant in 1998, little did he know that he would come across an exciting discovery 20 years later.
A school advisor once told Andrew Salisbury that entomology careers didn’t exist and suggested he go and work in a factory. Thankfully, he wasn’t dissuaded. Even as a young boy, the RHS’s principal entomologist kept caterpillars and cockroaches and was always the child that took animals home from school to look after.
Aged 12 he started recording insects while volunteering at the Herbert Art Gallery and Museum, Coventry. His passion for invertebrates eventually led to a PhD at Imperial College London on the host range and chemical ecology of the lily beetle. Salisbury currently works as part of the RHS Plant Health team, undertaking research and providing advice on pests and biodiversity.
Last summer, an unexpected discovery came across his desk: “It was a real first for me,” he says. “Finding a webspinner colony in a glasshouse at RHS Garden Wisley was absolutely amazing.” Salisbury was looking at Aposthonia ceylonica – proof of the first new insect order in Britain for 100 years.
Webspinners live in tunnels constructed from silk webbing, largely feed on decaying plant material and live in colonies. Aposthonia ceylonica is a tropical species that measures about 1cm long and feeds within the hanging roots of plants such as orchids and bromeliads. Generally found in Thailand, it is likely to have been imported via the plant trade.
“The confirmation of a new grouping is evidence of the role that globalisation has, and will continue to play, on what is found in our gardens,” says the entomologist. But this Embioptera order isn’t the only new discovery that has been made during Salisbury’s research.
He has recently completed a four-year Plants for Bugs field experiment to investigate whether the geographical origin of garden plants affected the abundance and diversity of invertebrates they supported. During this study, he collected a parasitic wasp, new to Britain, known as Heterospilus hemipterus.
Using 36 plots, each 3x3m, containing hardy plants native to the UK, the rest of the northern hemisphere (excluding the UK) and the southern hemisphere, Salisbury and his colleagues recorded tens of thousands of invertebrates.
All the plant groups supported large numbers of invertebrates, but the native plants were the most successful. The study also found that if plants were densely planted or allowed to grow, they supported a greater abundance of invertebrates.
“We expected more differences than there were,” says Salisbury. “The exotic plants did support really good numbers of insects, and almost as many as native.” He suggests planting mixed gardens: “Whatever you plant will support a range of species, but the more plants in flower, the better.” Jo Price
Salisbury uses a special Vortis suction sampler to collect invertebrates. Below: the tropical Aposthonia ceylonica.