Pollination can occur in several different ways, but usually plants rely on animals or wind to help pollinate them and help distribute their pollen and seeds.
However, a new study shows that apple trees produce bigger, rounder, and more desirable fruit when pollinated by insects in particular.
Researchers studied Cox and Gala apples, two popular varieties in Britain, and valued the annual contribution of insects to these fruits at just under £37 million (60 million USD).
'Insects are vitally important for producing a marketable number of Gala and Cox apples,' says Dr Mike Garratt, from the University of Reading who led the study. 'To maximize the quantity and quality of apples, we'd need to increase both the abundance and diversity of pollinating insects.'
The research was conducted on six Cox and Gala orchards in Britain. At each site, some of the branches were covered with a fine PVC mesh, allowing wind and rain to get through but keeping insects out.
As a result, trees that were left open to bugs yielded both more fruit, and a larger proportion of higher-value class-one apples.
However, unfortunately in the past 30 years, the number of managed honeybee colonies has fallen by more than half. Due to disease outbreaks, pesticide use, and a decline in the number of bee-keepers, bee populations are on the brink of collapse.
A recent study in the journal PLOS ONE said that more than half of European countries no longer have enough honeybees to pollinate their crops.
Dr Garratt suggests, 'Within the orchard, you can help pollinators by planting wildflower strips, maintaining hedgerows, and keeping a proper understory layer to the trees ... At the landscape level, what the insects really need are more native grass-lands and woodlands.'