Be Defended Against Invasive Pests

This cottony ash psyllid is an invasive pest and a recent introduction to our area. Black and Manchurian Ash trees and their crosses are particularly affected.

There are two generations of this insect a year. Adults are highly active and resemble tiny cicadas.

The ash psyllid feeds by means of piercing leaf tissue and utilizing plant juices. All of the damage is done during the immature (nymph) stage and can be severe due to feeding nymphs injecting a toxin into tree leaves.

Symptoms include curled or wilted (“cauliflowered”) leaves and premature leaf drop in summer. Feeding nymphs are surrounded by a cottony material enclosed within the leaf.

Since this insect overwinters as an egg and because the nymphs are protected by the cottony material, spray controls are almost ineffective and difficult to time. Spray control has been replaced with a systemic injection of OrtheneĀ®. The optimal time for application is bud break to June 15th. Injections can be done up to August 31st, but earlier is better in this case. Only one application is necessary for season-long control. Contact us today.

Source: City of Calgary