If your maples are looking a little less than spectacular, it is likely caused by an insect called Gloomy Scale. Gloomy Scale is an armored “scale insect” that attaches itself to the bark and sucks out nutrients, water, and sugars from the tree. In heavy infestations the tree will suffer from a lack of nutrition. This causes discolored leaves, cracking of the bark, weak and improper growth patterns and branch dieback. In many cases the tree can die if not treated.
How to Identify the insect? Take a look at the bark. Maple bark should be a medium gray to almost silver and smooth. Infestations of scale darken the color to almost black in some cases. The trunks and branch unions are usually the worst as multiple generations of the insect pile on top of each other. Up close the individual insect appears to be a small oval bump or “scale” on the bark about 1-2mm long.
Treat your maples! A once a year systemic insecticide applied to the soil or lower trunk can dramatically improve the health and longevity of the tree if caught in time. The treatment is applied on 2 consecutive years to ensure good control and then monitored on an annual basis to check for re-infestation. To repair the lost nutrients to the tree a deep root fertilization is recommended.
If you suspect your maples are GLOOMY we're here to help.