All types of bee and most other pollinating insects visit apple flowers to collect pollen and occasionally nectar.
- It is generally believed that honey bees play an important role in pollinating apple trees (Free, 1970).
- However, others have suggested that, as good crops of apples can often be obtained in conditions very unfavourable to the activity of hive bees, other vectors of pollen must also be involved or the trees must be more self-fertile than expected.
- It has been suggested that wild bees are also important pollinators although others contend that there are rarely sufficient wild bees to do this efficiently.
If bees and other insects are to perform adequately as pollinators, it is essential to create the appropriate climatic conditions within the orchard.
- Wild bees can be encouraged into the orchards by leaving grassy banks on headlands and by planting mixed deciduous species in windbreaks and various wild flower species.
- Flowering plants, such as corn marigold, are attractive to beneficial insects and may also prove attractive to insects involved in pollination.
- Work by the Oxford Bee Company (Gettinby, 2001) has resulted in the development of commercial nesting systems for Osmia rufa, the red mason bee, a UK native.
- Research conducted in several European centres indicates that red mason bees are much more efficient than honey bees in pollinating apples and other tree fruit species.
- They can also fly within a broader temperature range than honey bees and the dense brush of hairs on the underside of the females facilitates improved transfer of loose pollen between flowers.
- American research even reports improved fruit shape and texture, as well as improved yields as a result of pollination by red mason bees.
- The bees make nests in the holes made by beetles in dead wood and hollow plant stems.
Studies by the Oxford Bee Company have shown that one female red mason bee can be as effective in pollination as 120-160 honey bees.
- It is estimated that only 500 red mason bees are needed to pollinate 1 hectare of apples, compared to 60,000 to 80,000 honey bees.
- Fortunately, the red mason bee is not susceptible to the varroa mite which affects other native bees and is estimated to have caused a 45% drop in the number of commercial bee keepers.
- Artificial nests for these bees can now be obtained, which can prevent the bees being attacked by a wasp parasite.
- These should be located in sunny, sheltered south facing positions in the orchard in early spring.
- Further information is available on www.oxbeeco.com.