Cane borer's larvae eat aphids.
Once Tommy Cairns told me that, I quit worrying about it.

At least that's something to celebrate, Jeri! I'll probably be praying for cane borers when the aphids arrive. :-) I think the borers are only a problem in Feb. and March. Maybe I'll start pruning all my OGRs right after bloom (which probably what I should be doing anyway) instead of late winter/early spring. Would that give them time to heal cuts at the cane ends? Of course, I'll still have to seal the winter dieback canes when I cut to good wood. Grrr! Those darned borers dive 4-6 inches into the canes! They can really take down a smaller rose bush like Francis Dubreuil in record time. Sorry to rant! Borers are making me nuts this year. Carol

The pruning paste I sometimes use seems impervious to rain after a couple of hours.

Choosing cane borers over aphids sounds a bit strange..

I think that there are probably different cane borers in different parts of the country. Baldo said he had never seen a cane borer go below an inch or so into a cane.
I rescued a mature Elizabeth Taylor which had a badly bored cane. When the cane died two years later, I found the bore went eighteen inches down.

Generally when I pruned my HTs in Tennessee, I found damage to go four to five inches down.

What I found, that might be useful for some cane borers, is that they spring bore into freshly cut pith. When I could prune in early January/late December, I found that those canes didn't get bored, because (my interpretation) the pith got hardened. Prune at conventional times (as recommended by locals) and lots of pith damage, some of it at the edges of where I'd put a sealant on the cut surfaces and it hadn't sealed totally.

Cliffnotes: no simple one size fits all answers. Your garden needs your keeping records when things go copacetically right.

Baldo's right. In this part of the country, I've never seen a cane borer go more than an inch down -- and less, in most cases. So, really, ANY excuse was good enough for me not to bother. (I am a lazy gardener).

In more recent years, we don't cut into canes that would attract borers, so the point is moot. If the cane is healthy, we leave it alone. If it's in bad shape, we remove it.

But that's Teas and Chinas and the like, in Southern California. YMMV. :-)

Gee, I wish I lived in California with all those teas and Chinas! Well, okay, I would miss my colder climate OGRs, but the idea is tempting this spring. We are having warmer weather here in Portland, and I wonder if that has affected the borer population. I sure hope my borers are not the ones that get into raspberries. Those buggers are aggressive!

Nik, what kind of paste do you use? I wonder if it's available here. I tried one a few years back, and it washed away like glue does. I got lazy and started using glue again since it's handy. Someone over on another thread on the Rose Forum mentioned carpenters glue/wood glue. That might work better, but I'm now remembering that I tried something like that one year and it also washed off after a short while. Portland is very wet in the spring!

Ann, thank you for the prune time feedback! I may play around with that next year. I've been afraid to prune earlier than mid to late Feb. here in case new growth sprouted, and Portland suffered a cold snap. Have any of your roses suffered because of winter pruning? I wonder how long the borers hang around the area laying eggs. I hope they don't start multiplying and surviving around the year like some critters. I saw a huge garden spider in early Feb. You know, the kind that lays eggs in late fall or early winter and then passes away a la Charlotte's Web. I love garden spiders, but it was weird spotting one during the heart of winter! We seem to have more mosquitoes than ever, too.

Thank you all for the info! If others have ideas or experiences to share, please do chime in. I'm collecting notes and possible solutions. The borers have been an ongoing issue and are now becoming a rather problematic pest!

Gratefully, Carol

My issue too seems to be drilling bees who leave big holes, usually in main basal canes. The glue just drips right down. I would need a bottle of glue to fill it up!

I just hate spring spring pruning and having to keep cutting down and cutting down and ad nauseam. Oh well, there are lots of worse things to deal with. Carol, if you figure it out let me know? How about Vaseline?

Susan

I have absolutely no experience with cane borers, but I do remember reading about a sealant used for Japanese maples. I don't know if it fits in with organic gardening, nor do I know if it would work to deter the cane borers, but it is advertised to "protect wounds from insects". Phytec 50 cut paste

Thank you, Kat! I'll check it out. See below for what I'm resorting to today. Ha! Ha!

Hi, Susan. I'm sending you much commiseration! This is so painful, isn't it? I'm really worried about my Mr. Lincoln and a few other roses I cherish. Someone on your thread mentioned nail polish, so I went to Clemson University's Cooperative Extension site (which came up in a search), and the experts there gave clear nail polish a thumbs up. So, what the heck, right? I happened to have a mostly full bottle of the no formaldehyde kind in my bathroom cabinet, so in sheer desperation, I just weathered a small hail and wind storm and resealed my formerly glued roses.

Am I crazy? Maybe. In the next few days, I'll get to the hardware store and garden store and collect a sampling of the options mentioned by everyone. Today, I'm going for what's handy.

Please do continue to chime in, all. I have a creeping suspicion that my borer plague is NOT going away on its own, and there appear to be a number of us on the forum struggling with these beasts. I never thought I'd despise anything as much as blackspot!

Thank you! Carol

Clear nail polish can lift off of cut surfaces. I found Carpenter's Wood Glue (the browner of the two Borden wood glues) to hold on better than their white glue (and for gosh sakes, don't use a glue made for children because those are water soluble to remove it from places it shouldn't have been dumped by the little darlings.)

Thank you, Ann! You're a fount of knowledge!! Carol

What about Gorilla glue? It hardens when it gets wet. I don't know if it's safe to use though.

I wonder about a glob of Vaseline...it's a petrochemical though isn't it?

Susan

Gorilla Glue. That's an idea, Dingo. Or Liquid Nails. I practically reassembled an old house I used to live in with Liquid Nails. If I try it, I'll post results.

Susan, Vaseline might work well. It would shed the rain, and it shouldn't be too hard on the roses, but maybe the borers could push through it? Or would their wings and legs get all gummy? I have a non petroleum product (Unpetroleum Jelly) in my medicine cabinet, but it might not be as much of a barrier as Vaseline.

I almost want to sacrifice a couple of hybrid teas to test all these suggestions. I could turn rose borer tragedy into a crazy sort of amusement and a laboratory for furthering horticultural science! Carol

Ohhhh....I think liquid nails is a great idea! I'm sure I have something I can sacrifice to experimentation....I may try Vaseline too. Just smear a big ol glob on there. Critters can't get through that...

Susan

Ha! Ha! Don't mess with us, you ittle buggers! I'm going to experiment with a few different suggestions. Let me know if you find particular success, Susan. I just saw that borers got into The Prince in a very bad place, low on a main cane. Ditto on a very small, sentimental Red Pinocchio floribunda. Gorilla Glue is looking VERY attractive! Carol

I used some kind of tree pruning sealant that is apparently tar and very black. I originally got it for an old fruit tree. It worked the best of anything I tried, but eventually they drill right through it, too. Mine drill down really far, and they can hit so many canes! They are awful.

More recently I've just been sticking wires down the holes at intervals later in the season and stabbing any worm inside, lol. That works well and seems quicker than painting all of the cuts. That sealant is messy, so it takes more time.

I may take up your method of direct attack, Meredith! I'm really a pacifist at heart, but going head on with the borers might even feel just a tad bit satisfying. If they only nibbled a bit and moved on, I'd be all about live and let live, but my roses are under assault!

I feel less alone to know that others have shared my experience and survived. I've never spent so much time and energy keeping up a line of defense for the sake of my roses. This degree of damage in a such a short time is unprecedented!

Carol

I wonder if Rubber Cement would work . . .

Ooo, that's a great idea, Jeri! I have a tube around here somewhere. Look out cane borers! He. He. He. He. Carol

unless I am mistaken it sounds like you do your pruning at the same time of the year every year, correct? if you are experiencing borrers every year, then change the time you prune. If you are worried about pruning too early then put up with the winter kill look a little longer and prune later in the spring., I haven't had a problem with cane borers, ever (been growing roses since the mid 90's). up until 2006 my growing experience was in the willamette valley (McMinville and Albany) and now I am in Salem, OR, after living out of state for 9 years.

Hi, Brandon. Thank you for writing from my region! I have also grown roses here since the mid 1990s, and I've never had rose borer problems either until recently. I checked my neighbors' roses today and notice that many also have borers. The buggers seem to have moved in during the last couple of years or so. I can identify old holes from (at least) last year in my rose canes. Things have been rather hectic at my house, so I haven't been paying a lot of attention to my garden over the last two years. This year, the critters seem to be legion! They even bored through the Elmer's Glue and nail polish I just pasted on my Penelope. I really should prune my OGRs after bloom, anyway, so I think that's what I'll start doing. Due to time constraints, I've always pruned all my roses except ramblers in late winter. If my HTs and floribundas survive this spring, I'll seal them with something more durable each year and do what you suggest, prune them a little later in the springtime. Do you know when rose borers are done with the egg laying stage? I'm researching that topic. I'll be curious to hear if my neighborhood is an anomaly or if rose borers are becoming more plentiful in the Willamette Valley. Raspberries have grown in popularity in my area, so I'm checking out raspberry borer sites as well. Thank you again for your local feedback and any new info you discover. Carol

Mine come in the summer, and it seems as if they are active the whole time! I do know that I can take care of every hole in the spring and still have a heck of a time by late summer, even while pruning off the bits I see that have holes starting. They come back to them! It's cut and cut during the summer (part of why I just stab them now). The wood does fine with one hole of a short distance.

I always need to check in the fall and take measures for getting them very dead before winter. I can't swear to it, but I get the impression they burrow deeper over the winter. ??? They're pretty awful and do remind me of a blackberry/raspberry pest I have.

I don't know if you have a different sort of borers than we do, but the sort we have here (Coastal SoCal) tend to nest around decaying wood. For years, we had some old decaying tree trunks (remnants of old, old windrows) and as that material has finally decayed away, we see less borer activity.

OTOH, it may have something to do with the fact that we mostly don't prune -- and even this year are only removing deadwood.

What about bubble gum? Duck tape? :-)

Meredith and Jeri, I'm noting your feedback and thinking that (1) I'll need to continue sealing after cuts throughout the growing season and (2) I should make sure that I've cleared any wood or other similar debris. Jeri, after you mentioned wood debris, I realized that a weird coincidence occurred. My neighbors across the street moved, and the new owners are piling up and clearing out tons of wood and other landscape debris this winter/spring. They even raised the house and ripped out rotted portions of the foundation of their 1890s home and chunked the debris in dumpsters which remained in place for quite some time. Maybe they disturbed an overwintering colony of borers? That probably sounds weird, but really, SOMETHING went kablowy this year! Fortunately, My OGRs don't require as much pruning, deadheading, etc. as my few new fangled models. If I could get away with forgoing pruning, I would be thrilled. Alas, my collection tendencies and postage stamp lot have dictated pruning requirements. Big guys and gals like Madame Alfred Carriere will have to fend off critters after cuts or move along, however. There's no way I can wedge an orchard ladder into my side yard and glue all the cuts as I prune! Thank you both for your continuing info and feedback. The battle continues....

Summersrythmn, ha, ha. You might think you're kidding, but I've considered both! :-)

Carol

I basically live in a field clearing in the woods, lol. I really do get all kinds of borers in all kinds of plants! But the woodpeckers are a plus ;)