What is on my tree?!
It's difficult to see details on individual specimens. There seem to be two different stages of the insects: one that's all while, another that appears to have pale gray marks.
1.) Please try to to take closer views of both kinds. (If needed, perhaps a friend or neighbor might be able to help with that.)
2.) Then, to make verify the tree's D, include an image of a branch with several leaves.
If new images aren't possible, consider submitting 6 or more samples to the OSU Plant Clinic for a free ID and recommendations.
To do so, go to https://bpp.oregonstate.edu/plant-clinic/insect-id-clinic.
Once there, click "Submit a Sample" and follow directions. The insects are so small that you can collect them with the tip of a slightly moist child's paintbrush.
Thank you for the images. Unfortunately, they they don't reveal any additional characteristics useful for ID.
Consider gathering the samples this weekend so that you can send with them to the OSU Plant Clinic the first of next week. Recall that the submission form must go with them.
Oh, yes, thank you for the leaf images. The tree is a maple.