Repeated years of grazing the same buckthorn might kill it

I'd like to deal w/ buckthorn in the winter but I don't think I trust the effectiveness of my Garlon 4 (cut stump treatment) below 28°

Cut it all chest height and in the summer it will be am easy process to remove 6" and treat.

I'd rather only cut it once.

Is anyone battling it this winter? I usually take the winter off. I don't think Garlon 4 works below 28°.

I watched an episode of Ky Afield a couple weeks ago and the KDFWR are using helicopters to spray for bush honeysuckle on wildlife management areas. They are spraying late fall after the trees and other weeds and stuff go dormant but the honeysuckle still has green leaves. They said it is working really well. I believe they said they are even offering services for private land owners

Interesting. I had never heard of a copter being used. We must get creative though to mitigate invasives.

Saw it also. Interesting show. Guess the "project" to bring it in to improve habitat backfired. Eastern Ky is facing same thing with (not sure what it actually is ) but people call it Russian thistle. It was supposed to fill in around strip mines.

Any exposed soil can greatly exaccerbate the potential for problems

Hogs. Hogs will eat the area clean. Keep them grazing over the buckthorn infested area.

I was cutting buckthorn off at ground level and painting it with undiluted Crossroad earlier. But, with the colder temps and all the rain we've had, I don't know how effective it will be. I hate to keep hitting it if it's not going to kill it.

I agree with you. I tend to feel that if the 1st treatment doesn't kill it, then the person trying to eradicate it is doing something wrong. I think buckthorn is easier to kill than honeysuckle, but I use Garlon 4 for buckthorn & try to pull the honeysuckle. I'm interested in a fool proof way to kill honeysuckle, but all I've been able find so far is Tordon. I wuit using Tordon b/c it's too potent in my opinion.

I'd be interested to know the late winter/dormant effectiveness on killing it also. I think the determining factor would be; does honeysuckle have a suckering or non-suckering root system? In the late fall, the herbicide intake is high as the plant is storing root nutrients for the dormant season, I've been successful eradicating it then. If you stump cut it in the winter and spray and/or hack & squirt my concern would be that it comes back with vengeance but I have nothing to base that off of. I bought a new 40 recently and found a mature stand in two locations, I'd love to treat now but I also don't want to create a second effect and have it spread through the root system.

Following

When is the best time to cut and spray?

Around end of October… invasives tend to be the last and first things to green up- they really stand out.

Garlon 4, the oil based version, is very effective at low temperatures during the dormant season. I have dug ash stumps that were cut several weeks previously, out of snow banks, sprayed the outer layer with Garlon 4 (a mix of 25% Garlon, 75% bark oil and a splash of dye) and had zero sprouts the following summer. Temperature when I sprayed was probably 10-20 degrees F. I haven’t followed how effective it is on buckthorn but we use it for buckthorn and honeysuckle and haven’t seen resprouts.

Clark- thanks for the feedback. I found this excerpt authored by, Erika Segerson-Mueller, DNR Invasive Plant Program Specialist, Oshkosh titled: Winter Work: Invasive Honeysuckle Treatment I'm going to try it- as Clark mentioned, as long as it's treated upon cutting- resprouting should be minimal.


"Winter is a great time to treat invasive honeysuckle shrubs on your property since most other plants have gone dormant for the season. Winter herbicide applications are highly successful on freshly cut stumps, provided snow does not cover the cut surface. Basal bark applications may also be used on snow-free surfaces.

Stump cutting should be followed by herbicide treatments, as vigorous resprouting may occur from shrubs cut in winter but not treated with herbicide. Learn more about invasive honeysuckles and how to manage them on the Bush honeysuckles fact sheet from Renz Weed Science at the University of Wisconsin-Extension"

I was wondering about cutting the larger plants off in the winter if it's effective to kill the plant if you paint the stump with undiluted herbicide like Crossbow or Crossroads? I'd like to get back in the woods and start killing the larger plants off with this warmer weather. But, will painting the stump be a waste of time and herbicide?

They seem to claim you should treat the root collar too, not just paint the surface.