Poison ivy : copper and sulfur for knockback?

General Gardening
#21

Yup, I mow a fair amount of it too. Last year I learned a painful lesson though. PI oil stays on metal (like mower decks and blades) for quite awhile. I got a heck of a case of PI after changing my mower blades. Be careful

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#22

Full strength is not what you need! Not more then double strength. Full strength kills leaves immediately - they do not have time to send the poison to the roots. And this is what you need to kill it. You need to be patient with PI.

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#23

Iā€™ve sprayed PI with 2oz. 41% gly concentrate per gallon water, 4 oz. 41% gly concentrate per gallon water, and 6 oz. 41% gly concentrate per gallon water. All yielded the same, unsuccessful results. PI died back, appeared dead, then resprouted from the roots and looked perfectly healthy again.

I can spray PI once with Crossbow at 2 oz. per gallon water and it is Dā€¦Eā€¦Aā€¦Dā€¦and it doesnā€™t resprout.

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#24

The poison ivy spray concentrate made by Bayer seems to be the best. Better than straight 2-4-d,

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#25

For a Roundup substitute I prefer the Glyphosate by Bonide.

Works best in a side by side trial I did 2 years agoā€¦with Roundup, Sprectracide, and the Ace Hardware product. And Bonideā€™s product.

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#26

Really? Would not have expected that.
Never know really effects til u look for yrself

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#27

In addition to what others have noted about specific herbicides, there is some information in the UC IPM page on the timing of application.

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#28

Good to know. Thanks Vohd i bookmarked that page

#29

I had a bad problem with poison ivy at my place when I first moved here. What seemed to really help kill it was adding some dollar store dish detergent to the herbicide mix as a surfactant. I think it helped break down the oily coating on the PI leaves and let more of the herbicide get into the plant.

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#30

I forgot to mention CROSSBOW in my postā€¦old age I reckon.
Crossbow works just as well as the Bayer poison ivy product.
Both are way, way, way ahead of Roundup for poison ivy.

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#31

Iā€™ve been using 41% glypshosate 2 oz per gal for the last 10 yrs with success. That may be because Iā€™m only killing PI plants less than 1 yr old that have been seeded by birds.

4 Likes
#32

Oh nice. I like that idea. Thanks

#33

Ideally after i kill the current ocean i have thats where i will be at too.

#34

Ty for the info on comparisons BlueBerry :relaxed: