Flower flies promote growth

Q What are the little flying insects that seem to remain in one place hanging above plants? Is this a pest?

A No, this is a garden friend, an industrious wee creature that looks like a miniature wasp or tiny, slender bee, with yellow and black striping and fine, transparent wings. It hovers, helicopter-like, over flowers. This typical manoeuvre gives these helpful insects their common name of hover fly. They are also known as syrphid flies or flower flies.

These flies are usually the first flying insects to visit gardens very early in the spring and the last to leave in autumn. They pollinate our plants as they visit flowers to collect pollen and drink nectar.

Female hover flies lay tiny white eggs among aphids and other soft-bodied insects. The larvae that emerge are greenish brown, mottled maggots that feed on aphids for several weeks before going to ground and pupating. Soon more adults emerge to continue the cycle. There are four or more overlapping generations each year. Q The cedar trees around my new property developed brown parts, most of which blew off in a patch of rainy, windy weather. Are the trees dying? Picking up the dropped bits is tedious.

A This autumn “flagging” of cedar trees is a normal process of discarding old foliage. I agree that cedar dropping time is trying in gardens, as the itchy, clinging, dried foliage gets stuck in everything. In areas of the worst dropping in my garden I use floating row fabric to cover crucial plantings, like the winter lettuces and other leafy greens.

The fabric, arranged over other plantings, can be moved once the trees have shed all their dead foliage. I cover the compost heaps with old, discarded, lightweight curtains to eliminate the tedium of picking off cedar and other bits of autumn and winter debris. The curtains I have are from a friend, but thrift shops are a source as well.