Arborist Sleuth: Paint Flecks or Damaging Insect?
Written by: Jake Kubisiak, Certified Arborist, IL-1392A
Guess Which Insect?
A sloppy painter might finish up the ceiling work and call it day. Cleaning off the brushes with some water and flinging the excess moisture and leftover paint onto the shrubbery. Once this dries you might find tiny white flecks on the needles of your Mugo Pine (or other evergreen host). Maybe it’s a stretch, but this does come around to a tree care topic. These white paint flecks mimic the look of a tiny insect that can damage your trees or shrubs if left alone.
There are numerous types of scale insects. These tiny mostly sedentary insects suck sap from trees, shrubs, and vines. Predatory insects can keep their levels low enough to avoid serious damage to the plant. However, due to extremely prolific reproduction, populations can explode. Enough individuals can suck the life out of the plant. This particular scale insect adult female is about 1/8” long with a white hard shell scale covering that is about 1/3” in size (paint fleck size). Her children (crawlers) are very tiny, only about 1/32” long. They appear as a rust color on the green needles. There are two generations possible per year. They are very often found on Pines – and most commonly on Mugo Pine. They also occur on Austrian Pine, and less frequently on Spruce species and Douglas Fir.
Answer and Treatments:
The insect in question is none other than Pine Needle Scale. Since they are a hard shell type scale, you won’t find the sticky honey dew dripping from the plant. I find the best identification is the adult female scale that, at least in my mind, appear as dried flecks of white paint. These are usually distributed to small area or occasionally to most of the canopy. Adult females can produce 20-30 eggs each – not nearly as prolific as some of our other local common scale insects. The eggs over winter on the plant and can be controlled with a Dormant Oil treatment in early Spring. However, since we may not be aware of the insects until the growing season, a variety of alternatives treatments are possible. A call to Wachtel Tree Science will allow your Certified Arborist an opportunity to identify the Sloppy Painter or Pine Needle Scale and help guide any actions.