By the way, I’m using concentrated glysophate from the dollar store, mixed to a fairly strong solution.
Would not count on info from manufacturer or studies conducted by the manufacturer
How about the EPA?
Registration was renewed.
Worth noting that most grower seminars I have attended over the past 5 years mentioned that Roundup use was discouraged after a certain calendar date on tree fruit like Apples and Peaches after seeing damage in commercial orchards most likely from Roundup. I believe the max recommended use on tree fruit in my area was 2 times a year and not after June and use special care not to spray the suckers.
Not sure about the correct answer to the question but I sprayed a row or dense rye with Roundup and stuck elderberry cuttings in the ground in about 2 weeks after all of the rye was dead. Had 100% survival on the elders.
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No it only works on leaf surfaces it only harms roots if absorbed through the leaves. So it can stay active in the soil but it will not harm any plants.
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Glyphosate isn’t supposed to be very mobile in the soil. It binds tightly to cations in the soil. It’s basically a chelator.
That said, we’ve had lots of plant accidents and plant injury with gyphosate. For many seeds, the replant interval after using glyphosate is only 3 days. But we’ve found glyphosate stays active in the soil for much longer periods. We now wait a month before planting seeds after using glyphosate.
Our latest plant accident involved peach pits. Every year we plant several hundred peach pits for rootstocks. We always get high germination rates of these peach pits. Last summer, we planted several hundred peach pits, like normal. We covered the peach pits with soil in late summer. Some weeds emerged in the fall, so we lightly sprayed them with glyphosate.
As mentioned, we had already experienced several replant interval accidents in the past. But I thought the stone would protect the seed from any residual glyphosate which washed through the soil. Not so. Out of several hundred peach pits planted, only about 25 emerged. Some emerged with clear herbicide damage.
If it were me, I would avoid putting vines back on the sprayed grass, until after a good rain and some time.
It takes a very small amount of glyphosate to kill some plants. Last year we accidentally killed about a dozen one year old peach trees because of overspray. This wasn’t the first time this has happened. I’ve decided we are no longer spraying glyphosate around young trees.
A few days ago, I ordered a wiper to use glyphosate around young trees. I don’t know how well it will work. Certainly it will be slower than spraying, but tree mortality should be minimized.
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I accidentally sprayed some crab apple suckers a few feet from the main tree and it killed the tree.
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My exact thought initially.
Glyphosate/Roundup when applied to trees I cut down have been killing surounding trees in large #'s. I’m having 2-6 trees in vicinity completely die. It didn’t take long either… like a year after I put 100% Roundup on stumps with a paintbrush…
and its’ not the same-species, always… I may cut down a Poplar (which spreads via suckers) and have other Genus/species near it, dying.
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Thanks very much!
I used it to kill a large tree, about 16 inch diameter with no problems. I used 2 to 3 ounces drilled into the tree.
It’s happening to any size here. 16", 24", 12", 6" something near it turns crisp the following year.
Did you use brand Roundup? Some of their products contain other active ingredients in addition to glyphosate.
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No, I buy a gallon at a time when they go on sale for like 35 bucks from a Farm Store. It’s called Blain’s Farm & Fleet.
It’s all the same stuff. I shop for Glysophate never Roundup when online looking at stores, Dax.
Triclopyr 4 works better in my experience. It contains a penetrant - you’ll immediately smell it when the bottle is opened.
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If I do anymore trees again, I’ll try that.
Thanks.
Waited a bit and some rain, it looks like everything worked out well…
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Glyphosate news-
Many people continue to use glysophate for killing brush. As long as people use straight roundup or half and half it will some things nearby
Government researchers getting government desired outcomes. When roundup first came out,it was so expensive that farmers tried to be creative in lowering costs. Recirculating sprayers were developed to spray a horizontal stream across crop rows and catch all the stream that did not hit something above crop canopy in a container. to drain back to a pump to be sprayed again. A brilliant idea but a failure because dust that got into the stream neutralized the chemical and after a few hours they might as well be spraying water.
Another vote for triclopyr from me for controlling woody brush and trees. As with any herbicide, read the label and figure out what is safe and what is not. I’m using it to clear a bunch of brush from the area where I have pecan trees planted.
I’ve used glyphosate to kill trees in the past. It takes a very heavy dose and repeated spraying to do the job. Triclopyr is much more effective on woody plants.
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I have used glyphosate as brushed onto stumps at 20% concentration and it seems to work well like that. I have only done this for autumn olive (and one other tree - see below) so it may not work as well on other trees. But I have killed 100s of autumn olive at this point. It was recommended to me by extension as a way to get rid of autumn olive.
As a small aside, there was an extremely thorny bradford pear about 10 feet away from some pear trees I have. It was huge: 30’ tall and 1’ diameter trunk. I had trimmed it so the branches weren’t poking me, but then it had a million suckers coming up and was in the way and I was constantly getting stabbed by it. I had not yet joined this site (now I’d probably try to graft over it!) and also didn’t know about rootstock.
I cut it down and very very carefully spread some 20% glyphosate on the cut stump. The pear tree 10 feet away died.
Now, I’m supposing either it was an off shoot of rootstock somehow or the roots were touching underground or something.
I read this about Tordon and maybe something like that happened.
As another aside, I noted that @clarkinks had some autumn olive with good fruit. Maybe I should try grafting some of my autumn olive. Thought I’ve cut down 100s it barely made a dent in the amount I have - that just cleared my driveway and the area near my septic field.
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