Are all glysophate herbicides basically the same?


#41

Latex paint on the bottom of the tree may help protect the tree from Roundup. I use a backback sprayer when I spray Roundup around my apples or peaches to control where the spray goes. Its a lot more work than spraying from the tractor, but I can’t afford to take any chances. The large growers who spray Roundup with booms are bound to hit some suckers or tree bark.

I have not seen a problem from Roundup use so far, but I cut back when I saw a presentation on Roundup damage on apple trees at a grower meeting a few years ago. I got the impression that the experts are not sure if the damage is caused by hitting the bark, the foliage or build up of the glysophate or other ingredients contained in the spray in the soil

The presentation on Roundup damage caught my attention because most growers thought it was perfectly safe and did not exercise enough caution when they used it


#42

Blueberry, I recall some of the info you’ve shared here on gly. Good info.

I’ve been all over the place in terms of my concern of the trees using glyphosate. As it stands now I’m not too concerned about it. I’ve made enough mistakes, I think I’ve learned what I can and can’t get away with.

I’m using it primary on very vigorous peach trees with loads of organic matter to tie up the glyphosate. I add wood chips every year, so there is no lack of fresh organic matter.

I suspect the dynamic would be considerably different with things like dwarf apples on sandy soil.

I’ve not seen any effects on vigorous adult peach trees even if I hit the trunks or a little low hanging foliage with the boom sprayer, but I still don’t spray glyphosate after July 15th with a boom.

It’s always the young trees which seem extra sensitive to gly though.


#43

the dyes a good idea. got to remember that.


#44

Olpea

Its good that you have determined what you can get by with! I’m not that far along with my thinking, so I cut back on the Roundup.

I’m spraying more pre-emergent from the tractor in place of Roundup from a backback. This year the wet weather washed away the PRE early and I applied a bunch of N applied to make the B9 trees grow better. The weeds and grass were growing like crazy. I sprayed Glufosinate with the backback down the apple rows to get control. It does not control my weeds as well as Roundup but I hope its safer. Who knows for sure whats really safe until its to late?


#45

Tomorrow I plan on spraying Glystar around all my trees and blueberry patch. Long day ahead. :+1::heavy_check_mark:️:100:


#46

Something funny is going on with my peach tree. You can see the nectarine tree in the back in full flush and past the setting fruit stage. I sprayed concentrated glyso around the base last year (bamboo etc), being very careful not to hit the tree and I didn’t see any water sprouts, as the tree had been recently transplanted. It’s not moving past this “winter bud “looking phase. I’m guessing somehow the GS soaked through the roots. Perhaps the moles damage to the roots created an opening?


#47

Glyphosate can move through soil, but supposedly only if it’s very sandy. Of course any holes where roots were exposed would absorb glyphosate and probably kill the tree.

Organic matter doesn’t instantly bind glyphosate. I sprayed glyphosate once, then planted some tomato starts a few days later and the glyphosate killed the tomato starts.

It’s also recommended not to spray glyphosate after midsummer here. After that time the tree will translocate any glyphosate to the roots where it will not be broken down over the winter and continue to kill the roots all winter.

If you do get a little mist (and it only takes a very little mist) on a young peach tree it will kill it, no matter when it is sprayed (Been there done that more than once.)

Glyphosate is a very effective herbicide, but it’s very lethal to young peach trees.


#48

I sprayed glysophate to kill heavy growing grass around all of my trees last year.5 of which are peach. None of my trees have been planted and longer than since late March 2017. I didn’t lose any or have any I’ll effects whatsoever. In fact my trees did better not competing with all the grass for nutrients.


#49

Ok, Sounds like that’s what happened, thanks for the confirmation. I think I also lost a mature Kiwi vine last year from that tiny bit of mist you’re talking about. I was very careful, but it’s the most likely explanation. This is one of the reasons I’ve switched to trying landscape fabric around all my trees this year.


#50

Well dang it!! Quick and hard pop shower for 10 minutes and I hope my spraying from 11-2PM isn’t for not!! Pop up shower came at 330PM so everything had a minimum of 1.5 hours to dry. It was hot today too and only 30% chance for that pop up shower. It was 80 degrees and it looked like the spray was drying quickly and absorbed by the weeds/grass. All it takes is for it to dry right? Dry into the plant and any rain after that doesn’t matter…hopefully. What do you all think? Repeat in 3-4 weeks?


#51

10 minute shower more than an hour after spraying gly on a warm day shouldn’t be a problem. Assuming the gly sprayed also had an added quality surfactant anyway.


#52

Thank you!! Hope so!!

Are you referring to the “liquid dawn” I added in the mixture or another surfactant added in by the manufacturer of Glystar Pro?
The Glystar Plus shows a 14% surfactant added but the Glystar Pro (the one I used) apparently doesn’t have any added surfactant so I added 2 ounces of Dawn liquid detergent per gallon.


#53

Dawn is better than nothing, but it is always best to add a real surfactant designed to be added to gly. I’ve made the mistake of buying straight gly before (great price, probably due to not having a surfactant), I almost always have some type of surfactant around to use with other herbicides so I just used what I had.


#54

This may shed some light on another mystery: Two of my grapevines are severely stunted, and one appears dead. More information here:


These vines were exceedingly vigorous the first two years. Initially I thought the sharp decline was due solely to mole damage and the weakened root systems allowing pests and diseases to take hold. However, I recall spraying concentrated dollar store glysophate around the base of the grapes the same time as the Peachtree mentioned above. In both cases, there were no roots visible on the surface, broken or otherwise. But there were surely broken roots under the surface in the mole tunnels. Is it possible the glyso could have leaked through the soil and been absorbed into the roots that way?


#55

I think it’s possible. I wouldn’t want to give the impression glyphosate shouldn’t be used around trees. I sprayed (with a wand) glyphosate from the tractor seat to clean up some weeds a few weeks ago around some peach trees. I’m just very careful when it comes to young trees not to let them get any mist.

If I’m using a pump-up sprayer, may times I will stand between the little tree and the wand to further shield the tree from mist. Stuff super close to the young tree, I pull by hand.

You’ve mentioned mole tunnels. Maybe this has already been addressed in this thread (it’s so long I haven’t re-read it) but are you certain it’s not voles? Voles will eat the roots of the trees and kill them.


#56

I believe they are moles and the roots are collateral damage. Here’s The only one I caught. There are more in there:

Regarding the glyso concentrate, I just used it with a small hand sprayer and tried to be careful. I don’t know what kind of sticker it has in it, if anything, as it was very cheap. If I recall correctly it recommended to use it at 4x dilution. I used it straight.


#57

Rain that came an hour or so after I sprayed last Sunday appears to have not hindered my spraying effectiveness a bit. After just 4 days the grass/weeds are wilted and yellow. Looks like I a good kill and will save a ton of time this year not having to mow around each tree.


#58

Here in the States, most concentrate glyphosate mixes are 41% active ingredient. With that concentrate, the strongest mix for a pump up sprayer would be about 2% of the concentrate. Or a 1 to 50 dilution rate.

If the concentrate you are using is weaker, it still pretty strong to use it straight. Given that you used it straight, it sounds like that’s what killed the tree. I’m sure the margin of error is much smaller to use the concentrate without dilution.


#59

TSC has it on sale.

Compare-N-Save Grass & Weed Killer Concentrate, 41% Glyphosate, 1 gal.
Compare-N-Save Grass & Weed Killer Concentrate, 41% Glyphosate, 1 gal.
Qty: 1
$14.99 Was $24.99 Save $10.00
SKU#1013655


#60

The spots that I sprayed with mix from concentrate now have an infestation of moss and acid loving weeds that I rarely see. I guess I should be checking and adjusting the pH after mixing? What is the best way to lower the pH?