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This test probably helps you improve your false positive rate (accidentally identifying a safe plant as poison ivy), but if you just want to avoid it, the "leav

This test probably helps you improve your false positive rate (accidentally identifying a safe plant as poison ivy), but if you just want to avoid it, the "leaves of three, let it be" heuristic works pretty well. It's conservative, there are lots of things with three leaves that aren't poison ivy, but you at least won't get stung

hosh 4y ago
However, if you're intent is to gain skills in foraging or make medicinal uses of plants, then this is well worth the time to run through.
- habitue 4y ago
  Yeah, I really enjoyed it
micahdeath 4y ago
I get it second hand... Someone caries firewood with it, then sits in a chair. Later I sit in the chair and poof, I have it for weeks. For me it usually ends with steroids as it doesn't go away. (Last 5 times I've had it has been this way.)
- noduerme 4y ago
  Hyup. Last time I got it was from the arm of a chair too... no fun.
- bstpierre 4y ago
  I think my last round of it was second hand from myself on a pair of boots. Must have walked somewhere by it and gotten it on the laces, but didn’t actually get it on my skin, or washed well enough. Then on a day where I couldn’t possibly have gone near any ivy I ended up with a couple of spots on my fingers. And then again a week later before I realized it was probably on the boots. Fortunately just a minor inconvenience, but it’s crazy how the oil sticks around.
fsckboy 4y ago
this is more ambiguous than you realize: >This test probably helps you improve your false positive rate (accidentally identifying a safe plant as poison ivy) do you mean I will a priori spot a bunch of false positives but then learn to eliminate them, improving my false positive rating but possibly exposing myself to more actual poison ivy? or do you mean that my tendency to generate false positives will go up but I will be thus safer? I'm writing because I imagine you mean the former, but what happened in my case is the latter. I consider myself very very good at avoiding poison ivy, but this test was showing me varieties that I've never encountered before (the ones with leaves that have a shape with some concavities)
greenie_beans 4y ago
helped me improve my non-poison ivy identification
- pvaldes 4y ago
  Anything with opposite leaves growing in couples (see all maples) is not poison ivy. If all the leaves are simple is not poison ivy. They need to be composed by several leaflets Anything with five or more leaflets in the leaves is not poison ivy but could be poison oak or other poisonous relative. Some other Toxicodendron have 5, 7 or more leaflets. Check for how "soft" and flat is the surface and how the light is absorbed
slacka 4y ago
Yes, unless you are a botanist, you don't need the ability to identify a zoomed individual leaf. After about 10-20 Qs, I identified all 3 of the zoomed out poison ivy plants correctly, but incorrectly labeled 2 zoomed in leaves as poison ivy. In the real world, both of them I am familiar with and know for a fact they do not have leaves of three.

hosh 4y ago

However, if you're intent is to gain skills in foraging or make medicinal uses of plants, then this is well worth the time to run through.

habitue 4y ago
Yeah, I really enjoyed it

micahdeath 4y ago

I get it second hand... Someone caries firewood with it, then sits in a chair. Later I sit in the chair and poof, I have it for weeks. For me it usually ends with steroids as it doesn't go away. (Last 5 times I've had it has been this way.)

noduerme 4y ago
Hyup. Last time I got it was from the arm of a chair too... no fun.
bstpierre 4y ago
I think my last round of it was second hand from myself on a pair of boots. Must have walked somewhere by it and gotten it on the laces, but didn’t actually get it on my skin, or washed well enough. Then on a day where I couldn’t possibly have gone near any ivy I ended up with a couple of spots on my fingers. And then again a week later before I realized it was probably on the boots. Fortunately just a minor inconvenience, but it’s crazy how the oil sticks around.

fsckboy 4y ago

this is more ambiguous than you realize: >This test probably helps you improve your false positive rate (accidentally identifying a safe plant as poison ivy) do you mean I will a priori spot a bunch of false positives but then learn to eliminate them, improving my false positive rating but possibly exposing myself to more actual poison ivy? or do you mean that my tendency to generate false positives will go up but I will be thus safer? I'm writing because I imagine you mean the former, but what happened in my case is the latter. I consider myself very very good at avoiding poison ivy, but this test was showing me varieties that I've never encountered before (the ones with leaves that have a shape with some concavities)

greenie_beans 4y ago

helped me improve my non-poison ivy identification

pvaldes 4y ago
Anything with opposite leaves growing in couples (see all maples) is not poison ivy. If all the leaves are simple is not poison ivy. They need to be composed by several leaflets Anything with five or more leaflets in the leaves is not poison ivy but could be poison oak or other poisonous relative. Some other Toxicodendron have 5, 7 or more leaflets. Check for how "soft" and flat is the surface and how the light is absorbed

slacka 4y ago

Yes, unless you are a botanist, you don't need the ability to identify a zoomed individual leaf. After about 10-20 Qs, I identified all 3 of the zoomed out poison ivy plants correctly, but incorrectly labeled 2 zoomed in leaves as poison ivy. In the real world, both of them I am familiar with and know for a fact they do not have leaves of three.