Bugs

A client couple asked me to look at their Creeping Jenny (Lysimachia  nummularia ‘Aurea’).  A few weeks earlier it was vibrant as ever, but it quickly declined and lost most of its leaves.  I had a hunch what the culprit was, and my Saturday morning visit confirmed the problem was a sawfly larvae.

While there, the folks across the street, busy pruning their Shade master Locust (Gleditsia triacanthos ‘Shademaster’) flagged me down thinking I could help them determine why their tree had so little leaves in its centre.  The insect was Locust Plant Bug, a tiny but voracious eater. 

As I returned to the car, another neighbour headed over to show me his Birch (Betula papyrifa) that appeared healthy on the bottom half, but the top half had only a few leaves.  An easy diagnosis, as I showed him evidence of Bronze Birch Borer.  

Prior to 2009,when Premier Dalton McGuinty introduced Ontario’s cosmetic pesticide ban, I would have recommended Diazinon or Malathion as a cure for the Creeping Jenny, Cygon (Dimethoate) for the Bronze Birch Borer and a broad-spectrum systemic pesticide for the Locust Plant Bug. 

Today, 15 years later, when there are no pesticides available, I recommended pulling out and replacing the Creeping Jenny with Sedum for the first client, patience and tolerance for the owner of the Shade master Locust and a chain saw for the Birch. 

When Ontario’s Cosmetic Pesticide Act was first introduced, the horticulture industry thought the sky would fall.  We were quite wrong. 

Turns out trees have a pretty high tolerance level for insects. Aphids, once the enemy of roses and many flowering shrubs, rarely cause long term damage for home gardens. Caterpillars, the larvae of butterflies and moths, can eat foliage of ornamental plants without significant harm.

We have learned that home gardens can live happily without pesticides, and we have also learned that our previous wanton use of pesticides did more harm than good. 

We aren’t out of the woods yet.  Fruit growers rely on pesticides because consumers like to buy perfect fruit. Farmers use pesticides to achieve good yields in a competitive market.   The good news is that the agriculture industry is busy researching ways to reduce pesticide use with improved growing techniques, growing pest resistant varieties, and introducing natural predators. 

Next week’s Garden Clippings will deal with smart solutions for pests that bother home vegetable and flower growers.