Dormant strength LS (the variety I buy defines dormant strength as one cup per gallon) really should be applied with the applier wearing eye goggles, a heavy duty chemical respirator, clothes that can be totally washed (and maybe damaged by the S anyway) and skin protection. LS is what I used to force dormancy because it did kill all the hanger-on leaves. I'm no longer sure that leaf drop is that important and I've seen some signs of sun damage on south and southwest facing year old canes (that the leaves used to be protecting.) Dormant strength LS will cause a change in texture of new leaves that almost makes them look burned by excess heat/wind. Take a look at the new lower buds on your roses. If they are 'just' swelling, it's one thing. But if they are showing leaflets, your decision as to the strength of LS to use.

There seem to be a lot of chemists on this thread, so hopefully one of you can check my thinking here: Peracetic acid is created in large amounts by mixing concentrated H202 with concentrated acetic acid. But in the final dilution, there should be an equilibrium between the three compounds (H202, acetic acid, peracetic acid), in which peracetic acid is only present in small concentrations. However, peracetic acid reacts very rapidly, and the equilibrium provides a constant source of it as it is used up, making it effective even though it's only barely present. If this is case, shouldn't dilute vinegar and dilute hydrogen peroxide provide an almost identical product, if used immediately? The addition of a compatible surfactant, which seems to include common spreader-stickers and SLS, would bring it even closer. As far as I'm aware, acetic acid doesn't have any significant signaling effects on plants. Conveniently, salicylic acid is compatible with hydrogen peroxide - it's used as an aromatic stabilizer in cleaning formulas. I've long used hydrogen peroxide as a foliar "disinfectant" for ectoparasitic fungi and some bacterial diseases. It works - the main downside is the frequency of application, which is reflected in some of the studies linked above. Even full strength drugstore peroxide, 3%, doesn't seem to harm most plants as long as a small amount of spreader-sticker or surfactant is included to keep the drops from collecting/concentrated in small areas. It's pretty much equivalent to dilute bleach in this application, but without the hazards of applying sodium and chloride ions to leaves. I can't see the full paper linked in the original post - for those who have read it, how big was the difference between the treated and control? Often flat effectiveness is reported even when the actual effect size is very small.

For spider mites, I second Diane's advice. I've always heard that you do not need another chemical spray. Instead, water-spray (hard blast) with water-hose the undersides of leaves and repeat every few days. They should soon be gone. Back to your original problem, as seen in photos 1 and 2 (way back at the beginning of this thread)--if that is chili thrip damage, then is it also possible in Kansas? I planted a new rose last spring and by end of the summer, one cane started giving symptoms just like that first picture. I did radical surgery on it, cutting it down way below the strange growth, but then the lower new growth on that same remaining cane started showing the same damage. So I dug down into the soil and cut out that cane as low as I could. I haven't seen anything since, but by the time I did the last surgery, much cooler weather was moving in and none of my roses were doing any more growing, so I don't know if I solved the problem or not. All I know is that there are no signs now--but I keep wondering what will happen in the spring. I guess I'm wondering if chili thrips can survive freezing temperatures? Just in case my problem is chili thrips. We've had 12 degree temps here for a week now. By the way, that one cane was the only thing in my entire garden affected that way. I think the plant came from a California nursery, if that makes a difference. tropical--I'm so glad you have saved your roses! I just hope I don't have the same problem. Will have to review this thread next spring when my roses start growing again. Kate

I'm organizing the info. for future reference ***** Yes to black-peat humus as topping to buffer acidic rain, plus NPK of at least 10-10-10 for pots. Tested black-peat-humus plus horse manure (both alkaline) in 2011 for roses in the ground (clean past Nov), plus black-peat-humus potting soil (mixed with alkaline sand) for roses in pot in 2015 (Perle and Cloudert Soupert, both healthy until snow). Humus can hold the equivalent of 80–90% of its weight in moisture, and therefore increases the soil's capacity to withstand drought conditions.[32][33]The biochemical structure of humus enables it to moderate – or buffer – excessive acid or alkaline soil conditions.[34]https://en.wikipedia.org/wiki/Humus Above pic. is Perle d' Or, own-root in a pot with snow, winterized in my dark & unheated garage. Pic. taken the day before Thanksgiving, Nov. 25, 2015. It's 100% healthy, no pests, no diseases. Things I did right this year: Own-root from a tiny-rooting is wimpy & small. So put a 4" layer of soil mixed with alfalfa pellets ON TOP. That for constant release of nutrients, plus to lock in moisture. This was wet year. To buffer acidic rain, I put 1/4 cup of pea-gravel, for slow-release of calcium & magnesium & trace elements. Advantages: Pea gravel magnifies the fragrance. Pea-gravel scatters out and doesn't block out rain like big-chunk red-lava rock. Pea gravel is alkaline, so it neutralizes acidic rain. It rained so much I didn't bother with SOLUBLE fertilizer. I followed U. of Kentucky success with Omega 6-6-6 (blood meal, bone meal, sulfate of potash). I put high-bone meal fertilizer NPK 4-10-7 in the potting mix. Also topped with 1/2 tablespoon sulfate of potash, 1 tablespoon gypsum, and 2 tablespoon blood meal. This lasted for 2 weeks of constant rain.