Scratch test?

JLee9706

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How reliable is the “scratch” test for dying trees? I’ve heard that if you scratch the surface of the tree and it’s green underneath, then the tree is still alive and can be saved.
Thoughts?
 

Orion_metalhead

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I think it depends on the time you scratch the tree. For instance, if you scratch a conifer in fall, even if the tree is dead, it could still have sap and still have living tissue. I think the test is best when use in the early spring as trees are coming out of dormancy, because by that time, a dead tree wouldn't be moving sap anymore.
 

Forsoothe!

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I'll be a contrarian here. A scratch in the bark big enough to reveal something is a wound to a tree which is on the borderline in the first place, and secondly can easily be inconclusive or misleading. I don't pitch a tree until its been dead for six months. I the meantime I treat it the way I would a live tree.
 

Wires_Guy_wires

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Living tissue is no guarantee for survival or succesful rescues.
I think of it pretty binary:

Conifers - if you need a scratch test and the foliage is dead, it's beyond saving.
I find twig dessiccation more reliable in pines, if the twigs go wrinkly it's time to act fast. Recovery might be possible.
In junipers it's the foliage that tells a story. I have trunks that have been sawed bare two years ago and they're still green beneath the bark. But nothing will grow on them. How the foliage declines is a good indicator; if it dries to a crisp while staying green, no need to try. If it goes brown, there is a chance.

Deciduous - if you need a scratch test, and the foliage is dead, it might survive. If all the buds that form immediately abort or dry out, or the foliage drops right after leafing out, then it's a small chance.
But deciduous are a side husstle to me. I rarely kill those because I don't have many.
 

Bnana

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That one is definitely still alive but will be very hard to save with regular means.
Alive and or being able to recover are two very different things.
 

HorseloverFat

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I’m with @Forsoothe! , If I don’t know, for sure (normally by the time I’d consider scratching, it’s ALREADY a “speculative” move), I just leave ‘em be.... I’m normally correct in my “death notice”.. but I HAVE been surprised.
 
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