Scale on my tridents? Baby scale?

[Pepibom]

Apologies if this is obvious. A bunch of my young tridents and some Chinese elm have these little white lozenge shaped critters on their bark. They don’t move around and are easy to knock off with my fingers, they’re not armored like scale I’ve seen before. Would these pests be a type of scale? Going to wipe them off best I can with a little alcohol swabbing and use bonide’s systemic granules. If you all have some better techniques and can ID these as something other than scale I would appreciate it. Thanks.

 

[Wires_Guy_wires]

Looks like oystershell scale.
I would rub them off with a toothbrush and then shower the plant in ethanol (70%) a couple times. Since it's winter, this shouldn't harm your plant.

With this many, I'd skip the qtips and just spray.

If the problem persists into the growing season, consider using a systemic. Systemics wouldn't have much uptake in winter, so it's best to do some manual removal now and see what happens in spring.

 

[Shibui]

Oil based insecticides are usually effective for scales and should not hurt dormant trees. Oil based sprays are safer to use in cooler weather too.
You will probably need to get the scale covers off each one for the alcohol to be effective. Missing just a few will allow them to breed later in the year.
Systemics are very effective as the chemical gets to every one that sucks sap. I guess systemic is not going to work well while the tree is dormant so probably better to apply after they leaf out in spring.