Bees are very useful to us and not just for making honey. They perform an even more important function as pollinators. However, like a myriad of other insects, they have fallen on hard times around the world due to various stressors, from climate change to habitat loss due to pesticide use.
Scientists have suggested a variety of measures that can help beleaguered bees recover. One proposal recommends greening vacant land in cities to provide refuge for bees and other insects. Another suggests growing a diversity of flowering plants to benefit pollinators like bees.
Now, German researchers are offering yet another strategy: growing perennial hedgerows and flower strips in intensively cultivated gardens to help the wild bees that live in the area.
“To enhance wild bees in intensive agricultural landscapes, we need to provide a network of perennial flower strips and well-maintained hedgerows to create a continuous supply of flowers throughout the growing season,” says scientist Vivien von Königslöw. at the University of Fribourg. who was the lead author of a study on the results.
A hopeful discovery
The scientist and her team, who conducted their research from 2018 to 2020 in 18 apple orchards in Germany’s Lake Constance apple-growing region, found that the flowering periods of hedges and perennial flower strips complement each other, which increases the diversity and abundance of wild bee plants in the region.
As a result, if farmers plant a network of less rich perennial flower strips and hedgerows, they can go a long way to supporting wild bees while benefiting from their role as effective pollinators, scientists say.
The wild bees observed in the study visit flowering hedgerows in orchards early in the season, between April and June, then move on to perennial flower strips from June to August. That’s why a mix of perennial flowers like hollyhock and hollyhock is preferable to annual mixes, researchers say.
“Our results suggest a preferential implantation of perennial flower strips compared to annual flower strips because perennial flower strips flower much earlier in the second year of implantation than in the year of planting and attract different communities of bees throughout the season. ‘year. Therefore, they are more suitable for improving bee diversity,” says Von Königslöw.
Happy bees all year round
Flower strips greatly benefited wild bees by blooming during times when few flowers were present. Hedges, on the other hand, largely overlap in their flowering with apple trees and ground vegetation in spring in orchards.
“In landscapes with intensive agriculture, wild bees are rare due to the low availability of flowers as sources of nectar and pollen. This is a problem for farmers because cropping systems like apples depend on pollination,” the scientists said in a statement.
“To maintain wild bee populations, flowers that attract bees must be available throughout the growing season, but in monocultures of heavily flowering crops like fruit trees, flowers typically only bloom for a short period,” they point out.
By Daniel T. Cross. Articles in English