An emerging treatment proves promising for birch trees

What is Birch Leafminer and does it occur in Southern Alberta?

Birch Leafminers are sawflies, which are closely related to bees and wasps. They are among the most common insect pests affecting Birch trees in North America.

Native Birch varieties include Paper (aka Canoe Birch or Silver Birch), River, Bog (aka Dwarf Birch or Swamp Birch).

Areas inside the leaves are consumed by the larvae, affecting the leaves’ ability to produce food. Browning of birch leaves is apparent annually in mid-July and August, but the leafminers have been feeding inside the leaf tissue since early spring. Wikipedia

Are your trees infected with Birch Leafminer?

Calgary and Strathmore area homeowners are reporting Birch Leafminer as an issue in recent years. If you’re not sure if you have it, check birch trees for tell-tale brown patches on the leaves. This is evidence that caterpillar-like larvae are feeding inside your tree.

If I have an infected tree what can I do?

It is possible that left untreated, the Birch Leafminer infestation will be taken care of naturally as populations of wasps eventually get the sawflies under control. However, repeated infestation over a number of years can weaken the affected tree so intervention might be desired.

It is always a good idea to keep your birch healthy by ensuring it’s well-watered.

Landscape Plus is currently working with an arborist who will provide a service to treat your birch tree with a systemic insecticide. This relatively new treatment is a systemic injection, which looks promising with two-year effectiveness in combatting Birch Leafminer.

Is there a certain time of year that the systemic injection must be done?

The treatments must be done in mid to late May, so book now!

Did you know? The peeling bark of the Birch tree will add winter interest to your landscape.