Tree problems · Insect
Spider mites: signs and what to do
Spider mites is an insect pest, often seen on spruces, honeylocust, hemlock. Look for: stippled (speckled) yellow or brown needles on spruce.
General information, not a diagnosis. A certified arborist or your county extension office can confirm.
- Insect
- Spruces (spruce spider mite)
- Honeylocust (honeylocust spider mite)
- Hemlock
- Arborvitae
- Other drought-stressed trees
Signs to look for
Tick what you see. More ticks make it more likely, but only an on-site look can confirm.
0 of 6 signs ticked. Ticks stay in this browser only.
Season
Spruce spider mites are cool-season mites. Eggs overwinter, larvae hatch in spring, and feeding is usually heaviest in spring and fall, often easing in hot summer weather. Honeylocust spider mite females overwinter on bark or buds, lay eggs in late spring, and numbers often peak through July.
How it spreads
Mites are tiny and spread on the wind, on branches that touch, and on people, pets and tools. Outbreaks are most common on trees stressed by drought.
Where it is found
Spider mites occur across the United States. Check your state official map and your county extension office; ranges change.
Official sources
What to do
- 1
Hold a sheet of white paper under a branch and tap it. Look for tiny moving specks.
- 2
Check the underside of leaves or the lower, older needles for stippling and webbing.
- 3
Water the tree deeply during dry periods. Drought-stressed trees are the most open to outbreaks.
- 4
Try a strong stream of water on the foliage to knock mites off, as extension sources suggest.
- 5
Ask your extension office before using any spray. Extension sources warn that ordinary insecticides are often not effective and can even make mite numbers worse. Miticides are made for this job.
- 6
Take photos and ask a certified arborist if a valuable tree is losing many needles or leaves.
Safety first: do not climb, do not cut near power lines and do not use a chainsaw on storm-loaded wood. Call the utility for downed lines and 911 if anyone is in danger.
Prevention
Keep trees watered in dry weather, mulch the root zone and avoid root damage. Pick the right species for the site. Check spruces and honeylocusts at the times of year when mites are active so you can act early.
When to call a pro
Call a certified arborist if a spruce or honeylocust is losing needles or leaves, if you cannot tell mites from another problem, or before using a miticide on a large tree. Spraying tall trees needs the right equipment and licensing.
Not sure who to call? Read how to hire a tree service or check is my tree dangerous?
Trees it affects
Usually seen on: Spruces (spruce spider mite), Honeylocust (honeylocust spider mite), Hemlock, Arborvitae, Other drought-stressed trees.
See all species in our tree library, or pick a tougher tree with the tree picker.
For tree companies
How to explain spider mites to a customer
Explain that mites often follow stress, so watering and site care matter as much as a spray. Say plainly that general insecticides can backfire. Offer a simple plan: confirm, water, then treat only if needed.
Send this page to the customer after your visit so they can read the signs in plain words. See also selling plant health care and the job photo checklist.
Questions
What are spider mites?
They are tiny sap-feeding pests related to spiders. They feed on needles and leaves, and heavy feeding can turn foliage yellow, brown or bronze.
How can I check for them?
Tap a branch over a sheet of white paper. If mites are present, tiny specks will fall and may start to move.
Why do my spruce needles look speckled?
Stippling on older needles low in the tree is a common sign of spruce spider mites. Other problems can look similar, so ask your extension office to confirm.
Will water help?
A strong stream of water can knock mites off, and deep watering in dry spells helps trees cope. Ask your extension office what is best for your tree.
Should I use an insecticide?
Not without advice. Extension sources say insecticides are often not effective against mites and can increase their numbers. Ask about a product made for mites.
Will my tree die?
Healthy trees often survive. Repeated heavy feeding on a stressed tree can cause serious needle or leaf loss. A certified arborist can judge your tree.
Can Lirevon diagnose spider mites on my tree?
No. Lirevon is a remote marketing team for tree service companies and does not do tree work. This page is general information, not a diagnosis. A certified arborist or your county extension office can confirm what is wrong with your tree.
How do I find a good local pro for this?
Search Google Maps for certified arborists or tree services near you, read their reviews and ask for proof of insurance. Get two or three written quotes. Our guide on how to hire a tree service lists the questions to ask.
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