Good Bugs

Garden Clippings for November 4, 2017

In the garden, insects are both friend and foe.  We are not fond of spider mites because they suck the life out of junipers and spruce.  Japanese Beetles are among the worst offenders because the grub form eats grass roots and the adult form munches on a host of ornamental plants.  Several caterpillars eat produce from the vegetable garden before we get a chance to harvest.

There’s more.  Locust plant bug can defoliate Locust trees.  Emerald Ash Borer has done a devastating number on the areas’ Ash trees.  Birch continues to be troubled by Bronze Birch Borer and Birch Leaf Minor.

But it would be unwise to paint all insects with the same nasty brush.  Yes, several insects cause damage to ornamental and edible plants, but there likely exist a greater number of insects that provide benefit to the garden.  And there are swarms of insects that do no harm at all and therefore ought to be ignored.

Aphids in large numbers can gather in clusters and feed off tender leaves, but rarely do they cause serious damage.  Some gardeners suggest that the presence of aphids actually improves the blooming performance of many flowering shrubs.

Lady beetles are always welcome in the garden because they do a fine job of eating scale insects, aphids, mealybugs and mites.  We are all familiar with the adult Lady Beetles with their characteristic orange shell with black spots.  The Lady Beetle larvae, resembling a tiny dark alligator, are just as hungry as the adult beetle.

Praying Mantis is a fascinating insect with a healthy appetite for insects of all types.  Praying mantis has an odd triangular shaped head that can swivel in search of food like no other insect can.  Rather than fly, the Praying Mantis will sit and wait for bugs to cross its path, then pounce on its prey.

As school kids we learned that if a female Praying Mantis is hungry, she might opt to eat her suitor, perhaps even before choosing to hop in bed with him.  Praying Mantis’s defence mechanism is their green colour, making them almost impossible to find amongst green foliage.  Praying Mantis is often considered to be a beneficial insect in spite of the fact they will eat all insects, both good and bad.

Green Lacewings should be considered everybody’s favorite insect.  They have a voracious appetite, eating any soft bodied pests especially aphids and mealybugs.  Lacewings are so beneficial that they are grown commercially and are marketed to large greenhouses as well as home gardeners.

Ground Beetles will spend most of their lives under debris, logs and stones.  They eat up slugs, maggots, cutworms and other soft bodied pests that might invade vegetable crops.

Stink Bugs are wide bodied sizable green bugs shaped like a shield.  Although not usually present in large numbers, Stink Bugs rely on caterpillars and grubs for food.  Like Praying mantis, Stink Bugs have no way of learning the difference between good and bad bugs.