Poison ivy: Proper glyphosate ratio


Old 05-21-18, 05:05 PM
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Poison ivy: Proper glyphosate ratio

We want to kill poison ivy with glyphosate. Almost all the plants are widespread but in bush form, not thick stemmed vines. My research indicates 1-2% glyphosate is necessary. However, the container of 41% glyphosate says 2.5 ounces per gallon is required. All this gives me a wide range of mix ratios. I'd appreciate advice from someone knowledgeable in how to do this.

1-2% glyphosate means approx. 1.3-2.6 ounces per gallon (128 ounces). Conversely, 2.5 ounces of 41% glyphosate calculates to only 0.8 ounces per gallon. ( 2.5 ounces * 41% = 1 ounce / 128 ounces = .0.8 ounces) So, which is it?

BTW, my guess is 3.125 ounces. ( 3.125 ounces * 41% = 1.28 ounces / 128 ounces = 1%)

Thanks in advance.
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Old 05-21-18, 05:25 PM
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Bottom line, follow label directions with any product you choose to use. Quit doing the math and follow the label parameters.

Imo, having dealt with hard to kill poison ivy over the years, the best thing to use is a specific poison ivy killer that also says it's brush killer. For example: https://www.roundup.com/en-us/produc...ate-poison-ivy

This product recommends 6 oz per gallon. 18% glyposate and other ingredients.
Old 05-22-18, 05:09 AM
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I normally use 2 oz of 38-41% glyphosate per gallon of water but it can be a slow kill and sometimes I follow up with a second treatment a couple weeks later. The product XSleeper linked is good stuff and is more reliable in one application. The triclopyr in it is very good at killing woody and broad leaf plants
Old 06-01-18, 09:48 AM
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a lot of percentages on the bottles is regulated by epa, which for tough plants might not be enough, I use catt plex all the time works great on everything, but when I first started using it wasn't working on some vegetation I called the company they told me they were regulated to a certain percentage they could put on the bottle and to just double amount and I would see a huge difference. they were right
Old 06-01-18, 02:53 PM
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Simply double the recommended ratio for weeds to kill brush.

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