Bees Above Are Buzzing

Numerous studies in many parts of the world are showing a dramatic fall in insect numbers. They’re essential for agriculture, and essential in a garden where fruiting plants are grown, including our beloved tomatoes. Habitat loss, monoculture farming, and the widespread use of insecticides are among the reasons for this decline.

For a long time, many home gardens were unwelcoming to pollinators. We had monoculture lawns, heavily mulched and tidy flower beds, and until the pesticide act in 2008, there was regular spritzing and spraying of everything in sight, indiscriminately wiping out beneficent insects. This didn’t end pesticide use, only the formulas changed to comply with the law. Shelves are still filled with sprays and powders to rid gardens of pests, and beneficial insects can be killed just as effectively as before.

One of these important insects that specifically needs our help is the humble bee. Not including the honey bee, a non-native species, there are over 800 distinct types throughout the country, 400 of which can be found in Ontario.

But if it's honey you want, we rely on the honey bee. Did you know that a good part of your honey may have come from insect poop. Yes, you heard that right, and I apologise if you’re drizzling honey on your cereal right now. A study of the DNA in honey carried out by Noah Wilson-Rich, an entomologist who founded The Best Bees Company, revealed that fact and other valuable information. The study sampled urban hives in major cities across the US and the preliminary results are surprising.

We naturally assume that honey bees are busy collecting nectar and pollen from flowers, and we know they do because we watch them doing it. It’s a biased perception, however, as it’s easy to see the plants that bees are visiting in our gardens. We’ve not been paying attention to what they do at higher altitudes, and that’s one of the major discoveries that was made when the DNA in honey was studied.

The main sources of sugar in the honey tested did not come from wildflowers, but from trees, and not only from the blossoms; it also came from the excretions of sapsucking insects, particularly aphids, those pesky critters that drive gardeners wild when they find them munching away on plants.

What goes in one end of a hungry aphid is the sap that the plant depends on to grow and flourish. Too many aphids and the plant can die. It’s what comes out of the other end of the aphid that attracts the bees. It’s a sweet, sticky substance called honeydew. Besides nectar from flowers, honeybees are slurping up honeydew, and there’s often plenty of it. We might see only a few aphids on plants in our gardens; up in the treetops there can be tremendous numbers — easy picking for bees, and there’s even more food available when a tree is in bloom, far more than in a garden below.

Whether from nectar or from honeydew, the study determined that 75% of the sugar collected by honeybees came from trees and not from wildflowers, especially in an urban setting. Although more native wildflowers than ever are being introduced into urban gardens to benefit pollinators, there’s often a far wider range than is present in a natural, rural area. In Boston, where interest in urban beekeeping has grown dramatically, the honey sampled contained the DNA of 411 plant species. Because of this larger diversity of plants, the hives there appeared to be healthier and more productive than rural ones.

Another discovery made by the researchers was regarding the types of trees and flowers the honeybees preferred. Surprisingly, the flowers and trees favoured by them are not necessarily native ones. Honey bees don’t seem to care where lunch comes from. Even though coniferous trees are predominant in Seattle, the bees there favoured non-native linden and cypress trees.

Preferences varied from city to city because of the popularity of particular plants in a specific region. For instance, in New York, where even luxury hotels keep rooftop hives, the top three plants were locust and linden trees, and the flowers of sedum. In Portland, Oregon, known as the city of roses, no surprise that roses were in the top three along with begonias and sweet chestnut trees.

In San Francisco, where non-native eucalyptus trees have become an invasive species, there’s currently a debate going on whether to fell them or give them protection. The honeybees are not fussy. They’re such generalists, they don’t care that the trees are from Australia. They love them. Making up their top three favourites there are pine trees and rosemary.

Next time you hear buzzing in your garden, remember to look up, way up.