All I could say after seeing this was (less than scientifically) Yecchh! The poor thing has a tumor. I'll let someone else explain it but I'm glad you separated it from the plant. That cain't be good!

Thanks to your advice Ingrid, I was able to transfer these photos directly from iphoto to this post and they didn't contaminate my Houzz "idea book". You are right. This is disgusting. I did prune the top off, did "dip n grow" and will try to root the top of the cane which looked slightly wilted in a flower bud but otherwise OK. I rehydrated it first. This is insidious. I just noted the wilted bud and horrors! I should have recommended anti nausea meds before looking at the photo, and avoided mealtimes posting.

That is so interesting and helpful,roseseek. I dug into the cane and did find brown powder under the sunburned section. I scraped most of it off before the new photos. The "lumps" had white more normal looking plant tissue. I did not find actual maggots but can imagine they could have emerged already. This would surely explain this. Again, thank you because I had not heard of or considered this.

Sending borer sympathy, Sheila! I've gardened a long time, and my impression is that various borers have multiplied over the years. Good luck with the (now double) challenge! Carol

You're welcome, Sheila. Unfortunately, the only insecticide that can help with them is no longer available for home use. Lindane used to be available OTC from KMart! $9 a pint. You're likely familiar with the toxicity labels on products, where Caution is the least dangerous; Warning being the next and Danger being the worst. Lindane carried a Danger label with the first line being, "Causes blindness." It's the systemic stored in the wood, rather than in the foliage and fruit (supposedly). It's still available for State licensed commercial sprayers. I understand it is frequently used in commercial stone fruit orchards to prevent critters like these from attacking the trees. The best defense we seem to have against them at home is to maintain the densest, healthiest foliage cover possible to reduce the sun scald of canes. White washing the wood as has traditionally been done in citrus orchards for decades may also offer some help as the white wash (or light colored latex paint) reflects the intense sun rays, preventing them from cooking the bark and cambium, which attracts the insects and kills the tissues in the scald and above those areas due to lack of sap flow to them. The truly unfortunate part is, most often, there are more sun scalded areas with more of the maggots, so just when you think you've found them all, you likely haven't. Once found, you have to continue cutting into healthy cane to make sure you don't find any evidence of their downward travel under the bark. They keep eating downward until they hit the bud union or crown of the plant, where they will girdle it and kill it outright. I've seen evidence of old budded plants where the scions have died because of the borers but the stocks have continued flourishing because of their established root systems. It's very likely many of the old Ragged Robin, Odorata and Huey plants (among others) found in abandoned gardens remained after these and other insects took out the scalded wood of the roses budded to them. They AREN'T fun.

The first I learned of them was easily twenty years ago. I had watered my old Newhall garden very well, then traveled north to San Jose for several days as I was permitted to take cuttings of the imported roses for the Heritage to thank me for my efforts to gain them entry to gardens around Los Angeles. I returned home after four or five days to find my very old, own root, White Wings appearing as if it had been watered with gasoline. I grabbed the main cane and moved it to see if perhaps it was gopher activity and the cane snapped off in my hand. The borers had girdled it and the whole thing friend. Baldo Villegas, our now retired State Entomologist, diagnosed it as these borers and advised to maintain the thickest foliage cover possible to prevent the scald.

I will really work on the foliage protective aspect of this, roseseek. I'm sure you are right. Happily so far I think I got it all on this plant before it got to the crown. I had a few plants sunburn such that I thought to add a shade of dove weed to the base of the plant. Danae and Buff Beauty were particularly vulnerable. This is definitely worth avoiding. Better, lusher foliage will be my goal. Again, many thanks.

You're welcome, Sheila. Good luck!