Raintree Nursery Guide:
How to Perform a Scratch Test
Worried your newly planted tree or shrub hasn't leafed out yet? The scratch test is a simple, reliable method to check if it’s still alive—perfect for new growers.
The Scratch Test is a simple and easy way to check if the wood in your plant is still alive. If you are concerned your plant is failing to wake up from winter dormancy, perform a small scratch test in several different areas to see if the cambium layer is green and water and nutrients are flowing through the plant. Plants wake up from winter dormancy at various times, depending on the length of time spent in storage and your temperatures in the planting location. It is helpful to perform small scratch tests on wood before pruning, or if you suspect a portion of wood might be dead, to get an accurate picture of the health of the wood and whether it needs to be pruned off. As long as there is still green cambium at least 3” above the graft union, your tree can grow and thrive.
What is the Cambium?
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Beneath the bark is a layer of tissue called cambium, responsible for transporting water and nutrients.
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When healthy, cambium is moist and green. If a plant is dead, the layer turns dry and brown
Raintree’s Video Tutorial
We have created a short, helpful video guide that explains how to perform a Scratch Test.
Step-by-Step: How to Scratch Test on Fruit Trees
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Choose the spot
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For trees: select the trunk, about waist-high.
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For shrubs, berries, or vines: pick a cane or stem a few inches above the soil.
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Scratch gently
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Use your thumbnail or a clean, smooth knife.
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Lightly scrape away a small patch (1–2 inches), just through the bark to reveal the cambium layer. Avoid deep cuts!
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Inspect the tissue
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Green, moist cambium = ✅ plant is alive.
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Brown, dry, brittle wood = ❌ that part is dead.
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Interpret the result
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Green cambium on trunk at least 3” above the graft union = plant is viable.
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Dead trunk but sprouts at the base = rootstock alive, grafted part dead. New tree needs to be planted.
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Brown cambium on both trunk and rootstock = tree is completely dead.
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In bushes, vines, canes, or non-grafted seedlings:
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Brown cambium everywhere = the upper portion of the plant likely didn’t survive. Watch the root zone for new shoots from the roots.
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Tip |
Why It Matters |
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Small scratch only |
Prevents large wounds while checking viability |
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Avoid testing on buds/leaves |
Buds may die even if the plant is healthy |
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Wait before concluding |
Some plants stay dormant longer, especially newly planted ones |
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Photo record for warranty |
To submit a claim for store credit, please attach a photo of a scratch test 3” above the graft union that shows brown cambium layer. |
Why It Works
The scratch test looks directly at the key living tissue—the cambium. If it remains green, the pathways for water and nutrients are intact, meaning the plant is alive and capable of growth. It’s more accurate than waiting for buds to sprout or leaves to appear.
Frequent Questions
Q: Can I scratch test young saplings?
Yes—but be extra gentle. Young plants have thinner bark, so you only need a tiny scratch to check for green tissue.
Q: No green but soil sprouts?
Some grafted rootstocks may resprout even if the grafted scionwood above the graft union is dead. If that is the case, the named portion of the tree is dead. Although the rootstock may still be alive, it will not produce fruit of the grafted variety.
Q: Can I perform a scratch test on berries and vines?
Yes, pick a spot on a young cane/vine that is just a few inches above the soil line to scratch. The process is the same. You can also choose to prune back branches to find living tissue. It is not uncommon for individual branches to die back during winter dormancy. If you find no green cambium on any above-ground wood, wait several weeks to see if sprouting happens from the roots. Non-grafted bushes and vines will sprout true to name.
Q: Can I perform a scratch test on tubers, mushrooms, or strawberries?
No, you will want to look for new shoots or runners coming out of the ground to determine if your plant is alive.