Q.red stick dogwood
We have two red stick dogwood plants on the west side of our house. On one of them, the stem is covered in small white spots. The spots arrived around mid-summer and it’s now winter and they haven’t changed in appearance. They do not rub off easily, they are bright white and they look fuzzy, but they are not fuzzy when touched. Any ideas as to what it is and how do we get rid of it? Thank you.
If the white specks rub off they could be Scale.
https://www.gardeningknowhow.com/plant-problems/pests/insects/control-plant-scale.htm
In this case I believe you are describing lenticals.
Lenticals are small white spicks or spots on the branches. Their purpose is to exchange gas between the plant and the outside.
The will no be rubbed off from the branch.
This link has an image to compare to our branches.
http://courses.missouristate.edu/pbtrewatha/redtwig_dogwood.htm