2,4-D with Clopyralid is absorbed by roots of surrounding plants

[ShiverMinneapolisZ4b]

Looks like the herbicide 2,4-D mixed with Clopyralid can be absorbed by the roots of shallow-rooted trees and shrubs and does affect them.

This picture shows 2 Highbush Cranberry (Viburnum trilobum) 14 days after the ground cover weed Creeping Charlie was sprayed with lawn herbicides 2,4-D and Clopyralid around the base of the shrub in the foreground. Note the curling and spiraling of the leaf stems in the left foreground but relatively straight arc-shaped leaf stems on the shrub in the right background. Weeds were present from a distance of 2 inches to 36 inches from the trunk. The concentration used was 0.4% Clopyralid mixed with ~0.37% 2,4-D Amine – the latter approximately the same as the concentration out of lawn weed and crabgrass killer bottles attaching directly to a garden hose. Highbush Cranberry’s root structure is shallow and spreading.

I found a couple gardening-related posts stating that shallow-rooted shrubs can absorb 2,4-D through their roots, and that the half-life is 10 to 14 days in soil. I also found posts that the combination of Group 4 herbicides (auxin inhibitors) (such as 2,4-D and Clopyralid) has synergistic effects on weeds. Even though Clopyralid is supposed to be the more targeted herbicide that I use in prairie restoration, I see that it can be taken up by shallow rooted shrubs as well, especially if surfactant is used. I had seen my Creeping Charlie be practically unaffected by 2.4-D already, so my notes for that day would suggest I was trying to overcome what I thought was chemical resistance. I use the surfactant because my first treated weed for prairie restoration was Crown Vetch and it needed surfactant.

(Methods Section: 1.25 ounces of 41% Clopyralid and 1.5 ounces of “46.8% Dimethylamine salt of 2,4-D-Dichlorophenoxyacetic acid” was combined and mixed per gallon (128 ounces) water => ~ 0.37% active ingredient, along with a little surfactant “Alcohols, C10-16 ethoxylated; polyethylene glycol”. Application was via narrow fan nozzle from a backpack sprayer, aimed below leaves of the shrubs. Shrub height is ~ 5 feet; image shows top of shrubs. Application date 2026-09-11 during the the last 2 hours of sunlight, daytime temperature ranged 62-86°F, with temperature decreasing from high in hours surrounding application time.)

In prior years while doing prairie restoration, I’ve observed browning and dropping of spruce needles after weed forbs were sprayed around their base using the woody herbicide Triclopyr ester (“Garlon 4”). In that case the spruce trees own natural mulch had prevented forbs from growing within a foot of the trunk; trees were about 10-15’.

[treefrog1]

Yes, that is Triclopyr, and it is VERY effective as a basal spray on trees, woody vines, and brush. Sounds more likely that there may have been a little drift on to the stem or tree trunks.

[ShiverMinneapolisZ4b]

After you posted, I made corrections to my post and added a photo of the products used.

[ShiverMinneapolisZ4b]

I guess it’s back to glyphosate for spraying around shallow-rooted shrubs to control Creeping Charlie.

Pendimethalin is pre-emergent herbicide targeting annuals that germinate. I read it’s safe for use around fruit trees, but Creeping Charlie is not an annual and is established in many areas I would want cleared.

[KPS]

I rarely use 2 4 D anymore. The fumes can kill sensitive adjacent plants, and the herbicidal properties can prevent plants for a year or two in areas that were previously sprayed. This stuff is just too damn nasty.

Off brand glyphosate works perfectly fine for me. Buccaneer.

[treefrog1]

Yah, Creeping Charlie is difficult to control. Ive had best luck with Triclopyr 4, but obviously to have to be extremely careful around your bushes and trees. At the correct mix it shouldnt kill your grass.
Round Up will pretty much be neutralize by contact with soil, but its not real effective on Creeping Charlie.

[KS_razerback]

I bet you just had vapor getting your Vibernum with your temperature in the 80s. I find 24d choline to be the absolute best at not hurting things you didn’t spray while still being extremely effective.

[smsmith]

Back when I fought broadleaf weeds in my lawn, I found a mid to late October application of Triplet herbicide smoked creeping Charlie. A plus when applying herbicide at that time is that many ornamental plants are dormant or on their way to dormancy.

[JAF]

I found using 2-4d products on turf in October is great especially if you have sensitive plants near by. In the spring you are really clean.

The group 4 Auxin type herbicides have a lot of uses and work and targets different species of weeds. Certain 2-4D products are labeled to be sprayed directly over evergreens as a release from weed competition. You have to find the product labeled for it.

I’ve seen nurseries spray over the top of taxus or yews to control broadleaf weeds. Common practice. Seen it done with glyphosate too over spruce and fir when they harden off, but I never had the stomach to do that.

We used Lontrel which is (clopyralid) over the top of yews and boxwoods beds. Like hundreds of thousands of them. It has a narrow targeted species. It’s about as good as it gets to control Canadian thistle and clover. We’d hand spray colonies of thistle. If you had a sensitive plant it would show damage if you applied it heavily. I remember sweetgums looking curly after spraying thistle underneath it. It picked it up from the soil. We also had a big colony of Canadian thistle that glyphosate wasn’t doing the trick, so we sprayed it with Lontrel, probably too much. Thistles died but nothing would grow in that spot for two years as it stayed in the soil. Buckwheat or soybeans wouldn’t germinate.

We had an incident where someone went off label and sprayed fallow ground too heavily and we couldn’t use it for 2 years. Basically Leafy plants wouldn’t grow. It said right on the label not to use prior to planting deciduous shrubs. Some people got a talking to over that.

So they are a diverse group but they need to be used properly. Amines, Esters, Choline, triclopyr and clopyralid all act differently and behave differently. Quinclorac is group 4 and kills broadleaves and certain grasses. It’s a big time crabgrass killer.

There was a HUGE lawsuit about 15 years ago. Imprelis was supposed be the next great thing in turf weed control. They didn’t test it on shallow rooted evergreen trees. I saw norway spruce 40’ tall on golf courses that just up and died. A neighborhood in St Paul Mn. where you could see who used it by their dead landscape evergreens.

I think label rate 2-4d Amine is pretty safe as far as moving in the air or soil.

I used Alion as my pre emergent and creeping Charlie is pretty well controlled as far as seedlings.

I don’t use 2-4d or class 4 herbicides in my orchard. Just glyphosate. I guess I’m gun shy but I would hand spray 2-4 d Amine.

For turf it’s 2-4d Amine and Quinclorac. It rolls Creeping Charlie, clover, dandelion, and most annual crabgrass. I have too many things around to use the more volatile products in the middle of the summer.

[ShiverMinneapolisZ4b]

Updated my post – yet again. My notes for the day say I combined Clopyralid with 2.4-D, presumably because in nearby area of the yard I saw survival of Creeping Charlie when sprayed with 2,4-D alone even though it was late summer and allegedly the foliar spray would be “taken down to the roots” to work quickly. A native plants area is directly behind the affected plant, which is where I was working after passing the Creeping Charlie along the way.

[smsmith]

Clopyralid (tradename Stinger, Sonora, Transline, others)is some really nasty stuff. Your use is likely off label (e.g. illegal). Unless something has changed since the last time I read the label, it is not legal/labeled to use in residential areas

A quick perusal of the label and an internet search shows clopyralid is also ineffective at controlling creeping charlie.

[ShiverMinneapolisZ4b]

Thanks for pointing out the efficacy is available by search. I was heading into the prairie restoration with the tank mix. Of the prairie weeds I was spraying, search says the one I most wanted to target (Yellow Toadflax) is highly resistant to Clopyralid and it is most susceptible to Chlorsulfuron. That explains a lot! I already saw no benefit from spraying Clopyralid by itself. As for the Burdock, it says my mix was the right combination.

Up here the University of Minnesota lists Triclopyr as the most effective against Creeping Charlie, but I’ve already seen that affect my trees.

[smsmith]

I’ve not had issues with triclopyr being soil active/translocating, but I don’t use it around ornamentals. I have used it around fruit trees without issues, always on the lowest recommended concentration and without adding surfactant.

Clopyralid has one and only use for me…killing thistles in brassica foodplots. Even then, I will not use it if that plot is rotating to anything but a small grain or brassicas again the following year. It has a really long residual in some soils. I’d never use it in a residential setting. It can move vertically and horizontally in soil profiles. Just my $.02

[JAF]

How does the clopyralid affect the brassicas?

I rotated my clover food plot to Eagle Soybeans RR because my thistles were so bad. Cleaned them up pretty good with two sprays of Glyphosate.

Im following another two blocks with turnips and Radishes but thistle weren’t too bad. Broadcasted into the eagle beans and it’s a turnip carpet now.

[smsmith]

It does nothing to the brassicas, that’s why I use it. There aren’t many broadleaf killers available in the U.S. that you can use over the top of brassica crops

[JAF]

@smsmith

It does nothing to the brassicas

Do you spray over the top broad ast with a boom sprayer or just hand spot spray.

I good fact to know. Thanks

[smsmith]

I use a boomless sprayer on an ATV

[chinook]

The clue is here “Application date 2026-09-11 during the the last 2 hours of sunlight”
2,4-D is volatile, meaning in can gas off and travel. Late in the day the soil stays warm longer than the air above it. This allows the 2,4-D to rise and travel. Many of the group 4 herbicides have this ability. Always spray them early in the day.

[Quercus]

I try not to use commercial weed killers, usually use 20% solution of vinegar. But I made a big mistake using it in one of my larger greenhouses. I had 200 - 1 gallon conifers, plus blueberries, and maples. Was extremely careful, just spraying the weeds. Vinegar works pretty well at burning down weeds outside when it is hot and dry. In the close confines of the greenhouse with little air circulation, the vinegar fumes burned the needles and leaves. Lesson learned the hard way. I now have covered the ground with cardboard and black plastic. Going to cover that with gravel.

[treefrog1]

Agreed with @chinook , I found the best time to spray 24D for the weeds to take it in, for your grasses not to be effected, and for the least amount of drift is early in the morning, like as soon as its light enough to clearly see what you’re doing.