If you knew your winter lows which resulted in the browning of these plants, it would help others to guess what will happen to your palms. The windmill palm is rated zone 7 hardy, sometimes zone 6, but surely only when several years old. Your large Trachys should be ok after dropping the brown fronds. I wouldn't worry much if I were you. I have overwintered a young Trachy indoors, and it has brown fronds. I think mine have dried out. Your's will come back before mine.

Rainydaywoman, Musa bananas are zone 6 hardy, no worries for you.

Thx for the replies. I think it got down to 7 degrees, but I was in Mexico while the cold and snow were happening. Now the trachy has NO green and looks awful. I do hope it recovers.

Rainy, if you went down to 7F you must be zone 7. You may get more fronds, though. I guess it's a wait and see situation. This winter has been brutal, but I thought it was mostly towards the east, where the "Arctic Vortex" went. I wouldn't get rid of them for several months, you just may get more fronds.

My only suggestion is to wait. Windmill palms can recover from pretty massive damage so your palm may not be dead but it can take a while to show new growth, possibly as late as mid-summer.

Here is a link that might be useful: Is my palm dead?

Sorry I'm late in thanking you for advice. Now I can see a bit of green at the very top, but what to do with a tall palm with all those dead fronds? This part of Oregon is listed as zone 8, but now I'm treating it as zone 7.