Tree Service Glossary — A Plain-English Guide to Every Term You'll Hear

Tree service has a lot of jargon. Here is plain English for the 20 terms you will hear when you call McDonald Tree Service or any arborist in Massachusetts. Each definition is short — enough to know what you are buying, not so much that you will glaze over. I have been doing tree work in Middlesex County since 1995, and this glossary is the one I wish customers had before they call. If you need a real estimate, call (978) 375-2272 — free, in-person, no upselling.

(Think of this as the cheat sheet you keep on your phone while the arborist is talking. No judgment. We use words like "hanger" and "deadwood" like everyone knows them. Most people do not.)

The 20 Terms

Arborist

A professional who studies, manages, and cares for individual trees. In Massachusetts, look for ISA Certified Arborist credentials — that means they passed a national exam on tree biology, diagnosis, pruning, and safety. I have been doing this work since 1995, and the certification matters, but thirty years on the truck matters more. Both together is the combination you want. More about Keith McDonald.

Bucket truck

A truck with an aerial lift platform on a hydraulic arm. We use it when climbing is slower or less safe than riding up — usually on removals near power lines, large limb sections over a roof, or trees too compromised to climb. Not every job needs one. We tell you on the phone.

Brush chipper

The machine that turns branches into chips on the spot. The chips go into the chip truck and get hauled away — or left in a pile if you want them for mulch. The chipper is why tree removal costs what it does: hauling debris is half the job.

Canopy thinning

Removing select branches throughout the crown to let more light and air through. Most healthy trees do not need it. A lot of what gets sold as "thinning" is really just cutting branches to look busy. If the tree is healthy and you can see through it, leave it alone.

Climbing arborist

The person who goes up the tree with ropes and a harness to do the cutting. Distinct from the groundsman, who works the chipper and rigging on the ground. A good climber reads the tree — weight distribution, wood integrity, where the cuts go — before the saw starts.

Crane-assisted tree removal

When a tree is too big, too close to a structure, or too compromised to drop conventionally, we bring in a crane. The climber rigs sections to the crane, the crane swings them to the landing zone, and nothing touches your house. This is the "we're gonna need a bigger boat" moment of tree work. Our crane services page has the details.

Crown reduction

Shortening the overall height and spread of the canopy by cutting back to lateral branches. Not the same as topping — topping destroys the tree. Crown reduction, done right, preserves the tree's structure while making it smaller. Usually the last option before removal.

Deadwood

Dead branches still attached to the tree. They fall without warning — especially in ice storms and northeasters. If you have dead limbs over a driveway, a play area, or a roof, call us. Deadwood removal is one of the cheapest safety jobs we do. Think of it as the tree equivalent of fixing a loose shutter before the next storm.

Forestry mulching

A land-clearing method that grinds brush, small trees, and undergrowth into mulch on-site — no hauling, no burning. Faster and cheaper than traditional clearing for overgrown lots. We run mulching heads across Middlesex County for new construction and overgrowth cleanup. Our land clearing page explains when it makes sense.

Hanger

A broken branch stuck up in the canopy after a storm. It has not fallen yet. It will fall eventually — probably when you are standing under it. The most feared word on a tree-service voicemail. Call us before it falls on its own.

Hazardous tree assessment

A professional evaluation of a tree for structural defects that could cause failure. Bark separation, fungal conks at the base, cracks in the trunk, root plate lifting, lean changes — these are the signs. We walk the tree and tell you what we see. Sometimes the answer is removal. Sometimes it is not. More on tree health assessments.

ISA Certified Arborist

A credential from the International Society of Arboriculture. Requires passing a national exam and ongoing education. It is the baseline credential in the trade. The certification on its own is the smaller signal — thirty years of doing the work and 61 Google reviews at 4.7 stars tells you more. But get both if you can.

Land clearing

Removing trees, stumps, brush, and debris from a lot — usually for new construction, septic installation, or property expansion. Methods range from forestry mulching to full excavation. We do both across the 18 towns we cover in Middlesex County. Details on our land clearing service.

MGL Chapter 87

Massachusetts General Laws Chapter 87 — the Shade Tree Act. Governs public shade trees on town ways. Under this law, only the Tree Warden can authorize removal of a public shade tree, and it requires a public hearing. If the tree is on your private property, different rules apply — but the Tree Warden still matters for anything in the right-of-way. Several of our service towns have additional local bylaws on top of this.

Pruning vs. trimming

Pruning is selective — cutting specific branches for tree health, safety, or structure. Trimming is general — shaping a hedge or cutting back growth for appearance. People use the words interchangeably, but the work is different. We do both. We just call them by their names.

Risk assessment

Evaluating the likelihood that a tree or branch will fail and what it could hit. Combines visual inspection, species knowledge, and site conditions. A tree leaning over your bedroom needs a different risk score than the same lean over an empty field. We assess both.

Stump grinding

Using a stump grinder to reduce the stump to chips, 6 to 12 inches below grade. The fastest, cheapest way to deal with a stump after removal. The chips get mixed into the soil or hauled away — your call. We do this on almost every removal job. Our stump guide covers the decision in detail.

Stump removal

Digging the entire stump and root ball out of the ground. More expensive and more disruptive than grinding. Necessary when you are building on the spot or when the roots are damaging a foundation or septic system. For most homeowners, grinding is the better option. Grinding vs. removal — the comparison.

Structural pruning

Training a young tree to grow with a strong central leader and well-spaced branches. Done early, it prevents expensive problems later. A five-minute structural prune at year three saves a twelve-hundred-dollar crown reduction at year thirty. Most homeowners do not know this exists until the tree is already a problem. If you just planted something, call us now — not in fifteen years.

Tree Warden

A town-appointed official in Massachusetts who oversees public shade trees under MGL Chapter 87. Every town in our service area has one. If a tree is on a public way, the Tree Warden decides whether it stays or goes — not the homeowner, not us. We have worked with Tree Wardens in Billerica, Chelmsford, Lexington, and the rest of our 18 towns for decades.

Anything We Missed?

This glossary covers the 20 terms homeowners ask about most. If you heard a word on a job site or in a quote that is not here, call (978) 375-2272 and ask. I would rather explain it once on the phone than have you sign something you do not understand.

Don't Call Us If

You are looking for a textbook definition with Latin names and academic citations. This glossary is written for homeowners, not forestry students. If you need the academic version, the International Society of Arboriculture has a full technical glossary on their website. It is thorough. It is also exactly as exciting as it sounds.

Call Us

McDonald Tree Service, Billerica, since 1995. Tree removal, stump grinding, pruning, emergency work — across Woburn, Chelmsford, Lexington, and 15 other Middlesex County towns.

Call (978) 375-2272. I will come look at whatever you have got. I will tell you what it costs, what you actually need, and what you can skip. Worst case, I explain a word you could have Googled — but at least you got it from someone who has actually climbed the tree.