Left: Andy Salisbury sampling insects with a Vortis vacuum sampler. Centre: Helen Bostock on the ladder measuring canopy cover using a camera. Right: sorting the Vortis samples.
Project results and interpretation
By the end of 2017 two scientific papers had been produced and interpreted: on the flying insect visitors (pollinators) and the invertebrates inhabiting the plants. The key messages are summarised below.
In summary the key messages for planting for pollinators in gardens are:
• The best strategy for gardeners wanting to support pollinating insects in gardens is to plant a mix of flowering plants from different countries and regions.
• Emphasis should be given to plants native to the UK and the northern hemisphere, though exotic plants from the southern hemisphere can be used to extend the season (there are a greater proportion of exotic plants flowering later in the season compared to UK native and northern hemisphere plants) and provide nectar and pollen for some specific pollinators.
• Regardless of plant origin (native or non-native), the more flowers a garden can offer throughout the year, the greater the number of bees, hoverflies and other pollinating insects it will attract and support.
Invertebrates on the plants:
The second scientific paper from the project reports on the abundance of invertebrates that were found on the plants, including those feeding on living plant material, on decomposing organic matter, and all other invertebrates, excluding pollinators. It was published in Biodiversity and Conservation in July 2017
The key messages for gardeners wishing to provide habitat for invertebrates were
• To plant a predominance of plants native to the UK.
• Planting schemes that are based on plants originating from the Northern Hemisphere (near-natives) may support only marginally fewer (less than 10%) invertebrates in some functional groups (including herbivores and some predators) than UK native plant schemes. Plant schemes based on Southern Hemisphere (exotic) plants will still support a good number of invertebrates, albeit around 20% fewer than plants from the UK.
• Regardless of plant origin, the more densely a planting scheme is planted or allowed to grow, the more invertebrates of all kinds (herbivores, predators, detritivores and omnivores) it will support.
Salisbury, A., Armitage, J., Bostock, H., Perry, J., Tatchell, M., Thompson, K. (2015). Enhancing gardens as habitats for flower-visiting aerial insects (pollinators): should we plant native or exotic species? Journal of Applied Ecology 52:1156-1164.
Salisbury, A., Al-Beidh, S., Armitage, J., Bird, S. , Bostock, H., Platoni, A., Tatchell, M, Thompson, K. and Perry, J. (2017). Enhancing gardens as habitats for plant-associated invertebrates: should we plant native or exotic species? Biodiversity and Conservation