What is it?
Woolly elm aphids is an tiny insects that require two hosts (American elm & Saskatoon) to complete their life cycle. The insects alternate between two hosts and cause damage by sucking sap from them.
Symptoms
- Infested Saskatoon plants have low vigor and less fruit production , even plants death.
- Roots of infested Saskatoon appears fungus-like substance in white with purple/blue hue.
- Leaves of American elm swell and curl with cottony substance.
Damages
- No permanent damage caused to American elm, mainly aesthetic problem.
- However, it reduces vigor and fruit production of infested Saskatoon. Severe infestation can kill the Saskatoon.
- Honeydew from aphids creates nuisance sticky substance on items under the tree.
What to do?
- Regularly monitor your plants.
- Inspecting roots of Saskatoon remove severe infested plants.
- Some pesticide can help control aphids on elm but no product can effectively control aphids on the roots of Saskatoon.
- Removing elm trees or controlling aphids on elms won’t prevent Saskatoon plant infestations because aphids can travel long distance via wind.
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