Warning signs you can check from the ground
- Dead or bare branches over half the crown. No leaves in June on one side, or a top that has died back. A tree that is more than half dead rarely recovers.
- Fungus at the base or on the trunk. Mushrooms, shelf-like conks or soft, punky wood near the root flare usually mean internal decay, often far more than you can see.
- Cracks and splits. A vertical crack in the trunk, or a split running down from a fork, especially a tight V-shaped fork where two trunks press together with bark trapped between them.
- A new or worsening lean. Many trees lean safely for decades. A lean that appeared after a storm, with soil cracked or heaved up on the side away from the lean, means the roots are failing.
- Cavities and missing bark. Large hollows, woodpecker holes in a line, or bark falling off in sheets.
- Hangers. Broken limbs caught in the crown after a storm. These fall without warning and are one of the most common causes of injuries.
- Root damage. Roots cut by a new driveway, foundation, sewer or utility trench within a few feet of the trunk.
Rockland's most common hazard trees right now
Ash. Emerald ash borer has killed most unprotected ash across the lower Hudson Valley. Dead ash dries out and becomes brittle within a couple of years, and crews often cannot safely climb it, so it costs more to remove the longer it stands. Beech. Beech leaf disease has spread through the region's woods; badly affected beeches thin out and decline. Hemlock. Hemlock woolly adelgid has killed many hemlocks in the Highlands and on north-facing slopes. Oaks near new construction. Oaks are sensitive to root damage and often decline two to five years after nearby digging. Norway maple, silver maple and Bradford pear. Weak forks that split in wet snow and nor'easters.
What a professional tree risk assessment covers
Under the industry's standard practice (ANSI A300 Part 9 and the ISA Tree Risk Assessment best management practices), an assessor looks at three things: how likely a part of the tree is to fail, how likely it is to hit something (a house, a driveway, a play area, a road), and how bad the consequences would be. There are three levels:
- Level 1, limited visual: a quick look from the ground for obvious defects, often used across many trees.
- Level 2, basic: a full walk-around of one tree with simple tools (mallet, probe, binoculars), checking the root flare, trunk and crown. This is what most homeowners need.
- Level 3, advanced: extra testing such as resistance drilling, sonic tomography, a climbing inspection or root-collar excavation, to measure decay inside a valuable tree you want to save.
A good assessment ends with options, not just "take it down": removal, crown reduction, removing dead wood, cabling or bracing, or simply monitoring and re-checking in a year.
ISA arborist or tree company?
Most Rockland tree companies will look at a tree and give a free removal quote, and for an obviously dead or storm-damaged tree that is all you need. For a large, healthy-looking tree you would rather keep, or when you need a written opinion, ask for an ISA Certified Arborist, ideally one who holds the ISA Tree Risk Assessment Qualification (TRAQ). A consulting arborist who does not sell removals gives the most independent opinion; a written risk assessment is usually a paid service, so ask the price first. New York State does not license arborists; what Rockland requires is the county home improvement contractor license for the company doing the work.
Why the paperwork matters in Rockland
Several Rockland municipalities exempt dead or dangerous trees from their permit rules only if you can prove the condition: the Town of Clarkstown wants documentary evidence within seven days of removing an imminently dangerous tree, and dead trees verified by the Town or a certified arborist; the Village of Pomona wants a licensed arborist's verification filed within 48 hours of an emergency removal and needs an arborist's finding to approve more than three trees a year; Upper Nyack wants an ISA Certified Arborist's written determination within 48 hours; Nyack allows dead or hazardous trees with an ISA arborist or landscape architect report; Montebello asks for proof such as an arborist's report for dead trees. Take photos before anything is cut, and keep the arborist's letter. Our Rockland permit table has each town's rule.
When it is an emergency
Call for emergency service when a tree or large limb has fallen on a house, car or driveway, is actively cracking or leaning further, or is resting on wires. Stay out of the drop zone, keep people and pets away, and call Orange & Rockland first for anything touching a power line; never let anyone cut a tree that is in contact with a wire before O&R makes it safe. Then see our emergency tree removal page for the first hour. A tree that is merely dead but standing still is urgent, not an emergency: book it before the next storm, not tonight at storm rates.
Hazard tree questions
How do I know if a tree is going to fall?
No one can predict it exactly, but the strongest warning signs are a new lean with cracked or heaved soil, fungus or soft wood at the base, deep trunk cracks or splitting forks, and more than half the crown dead. Any of these near a house is worth a professional look.
What does a tree risk assessment cost?
Most tree companies give removal quotes free. A written risk assessment from a consulting ISA arborist is usually a paid service, and the price depends on the level of assessment; ask before the visit.
Is a leaning tree always dangerous?
No. Many trees grow with a lean and are stable. A lean that is new or getting worse, especially with lifting soil or exposed roots on the opposite side, is a warning sign.
Do I need a permit to remove a hazardous tree in Rockland?
Most Rockland towns exempt dead or imminently dangerous trees, but some require proof afterward, such as photos or an arborist's letter within 48 hours (Pomona, Upper Nyack) or seven days (Clarkstown).
Should I remove a dead ash tree?
If it can hit anything you care about, yes, and sooner is cheaper: dead ash becomes brittle quickly and soon needs a lift or crane instead of a climber.
How it works
- Tell us about the job. Your town, what you need, and a photo if you have one. Takes about a minute.
- We match you with a local tree pro. An independent Rockland County tree care company that holds a Rockland County home improvement contractor license and carries liability insurance, and that actually serves your town.
- Get a free on-site quote. The company contacts you directly, looks at the tree and gives you a written price. No obligation, and you deal with them from there.