Looks like old woodpecker or sapsucker damage. If the tree looks healthy, don't worry about it.

The thing is, it's on half a dozen branches in all different orientations, so I don't think a bird would be doing this 360 degrees all around a branch.

a sapsucker is a woodpecker.. so im not sure what they are called in your area ...

check out these pix ... hit the WEB button to read up ... ken

https://duckduckgo.com/?q=sapsucker+damage&t=ffcm&iax=images&ia=images

Ok...I'm coming around to the idea of a sapsucker. Fortunately, the damage is limited to a single "line" on several branches. Maybe these were explorations that were unproductive and the bird moved on, rather than causing the huge damage I've seen in some photos.

Sapsucker damage seldom affects the plant's general health.

I once visited a garden where a venerable, old, still productive pear tree looked as if it was made of pegboard.

The only plant that I have had really damaged by sapsuckers is Sequoiadendron giganteum 'Pendulum' and part of the plant's response may be that it is out of its native range. I cut the 30' trees off at about 3' and am very curious to see what happens...the lower growth is vigorous.

I have lost two Sequoiadendron giganteum 'Pendulums' to Sapsuckers, but hardly a mark on the species Sequoiadendrons in my garden. The third pendulum, and oldest, is struggling because of the Sapsuckers. They have even attacked a few large rhododendrons!

I find these issues with 'Pendulum' rather surprising as most specimens here are so fully and densely clothed in the hanging sprays of foliage that the bark is fully covered......often by several inches of thick needles!

In fact, I rarely see sapsucker damage on any evergreen, conifer or broadleaf. But it can appear on just about any deciduous tree in my area.

Mike I have heard from others up there that sapsuckers are a problem on 'Pendulum' as well. I have many other dwarf Sequoiadendron that are untouched, although no species. The only other tree here showing sapsucker damage is Carpinus. Go figure.

Local friends with a 'Pendulum' of some size get sapsuckers on it, may have said something about this being a problem. Meanwhile the tree was all still there, last time I looked. Certainly the birds have not been having the same effect as cutting it off 3 ft. above the ground would.

Speaking of heavy pruning Ceanothus often do not come back well from cuts made into old wood. In this respect they are like brooms, heathers and lavender.

I decided that I din't want 20+ feet of dead trees staring me in the face.

Like this? :-) I probably will cut this one down this summer when the pond is dry. Most of the top is dead and some of the branches lower down are dead too. This tree was fully clothed at one time, but the Sapsuckers hid under the branches and did a lot of damage before I discovered it. I don't know what I could have done to stop or discourage them. I'm sure as heck not going to shoot em'. This tree was planted in 1979. Hinoki on the right planted at the same time.

Here's a close-up.

yep! The tops of mine were completely dead (maybe the top 2') and the rest of them looked like yours. The bottom 3' or so are lush and robust. We'll see what happens. One of them is already releadering. It's a stopgap measure though; it will just happen all over again I am sure.

Looks like Mike's been getting drunk and firing shotguns at his trees.

Here are mine. In their former glory (when they were still quite young) and today!