Facilitation or competition for pollination between invasive and native plant species?

by Valérie Cawoy et al.

The invasive Giant Balsam (Impatiens glandulifera) - Photo: A. Vervoort

Plant species that invaded regions where they did not occur before can have deleterious effects on the native flora. They are often ‘supergeneralists’ that attract large numbers of insects with high amounts of nectar and pollen. This may lure pollinators away from co-flowering native species in the surroundings. Consequently, these native species receive less visits and less pollen is transferred, which could lead to reduced fruit and seed production. On the other hand, so-called facilitation effects have been also observed, where the invaders attract pollinators to a patch of flowering plants and may thus increase flower visits to native species.

Read the whole summary: in English or in French
Read the scientific publication in JPE.

The Importance of bee pollination for commercial sour cherry production in Denmark

by Lise Hansted et al.

Low fruit set, despite normally-developed flowers in Spring, is often a significant contributor to poor yield in the self-fertile sour cherry (Prunus cerasus) cultivar ‘Stevnsbaer’ in Denmark. This study set out to investigate the effect of insect, and particularly, bee pollination on the fruit set of this cultivar, to provide information for beekeepers and cherry growers concerning the potential benefits of placing bees in the orchards.

A flowering sour cherry branch caged with wire mesh and tulle net, allowing wind through whilst keeping insects out

Read the whole summary: in English or in Danish.
Read the scientific publication in JPE.