---
title: Buttress Roots: The Wide Base of a Big Trunk
url: https://battleborntreeservice.com/glossary/buttress-roots/
business: Battle Born Tree Service
address: 6301 US Highway 50 East, Carson City, NV 89701
phone: 775.232.8243
hours: Office Monday-Friday 8:30 am-5:00 pm; phones answered seven days a week; 24-hour emergency service
credentials: ISA Certified Arborist WE-11728A on staff; Nevada Business License # 20131580674; fully insured
type: Tree service (removal, crane work, pruning, stump grinding, defensible space, snow removal, firewood)
---

- [Home](https://battleborntreeservice.com/)
- [Arborist glossary](https://battleborntreeservice.com/glossary/)
- Buttress roots

# What are buttress roots?

Buttress roots are large, thick roots that swell out from the base of a trunk and run along the ground, giving the tree extra support on the side where the load is greatest. They are part of the [root flare](https://battleborntreeservice.com/glossary/root-flare/).

## How they differ from the flare

The root flare is the general widening where trunk becomes root. Buttress roots are the biggest and most visible members of it, found most clearly on cottonwoods, willows, elms and large old trees. They often show on the windward side or on the side that bears the lean, because trees put extra wood where stress is highest.

They act like the legs of a table. Together with the [structural root zone](https://battleborntreeservice.com/glossary/structural-root-zone/) they set how well the tree stands up to wind.

## Why it matters in Northern Nevada

Large buttress roots meet sidewalks, driveways, curbs and house foundations, and that is where many cases of lifted paving start. Owners are tempted to cut such a root; the risk is to the tree's stability. Cutting a major buttress root can take away a good deal of the tree's anchorage, and the tree can fail in the next big wind. See [tree roots, sidewalks and sewer lines](https://battleborntreeservice.com/guides/tree-roots-sidewalks-sewer-lines/).

Trenching for new utilities close to a trunk is the other threat. Call 811 before digging and keep the trench outside the structural zone where you can.

## What an arborist does about it

Before any root work the arborist looks at how large the root is, where it sits relative to the trunk and what it supports, then talks through options: re-routing a path, bridging pavement over a root, shaving a walk, a [root barrier](https://battleborntreeservice.com/tree-services/root-barriers/) for the future, or, if the root is essential and the damage cannot be avoided, removing the tree. Large roots are not cut casually, and the arborist will say when to leave one alone. Battle Born's certified arborists assess this before any root work is quoted, and the estimate is free.

### Sources

- [International Society of Arboriculture, Trees Are Good: Avoiding Tree Damage During Construction (brochure)](https://www.treesaregood.org/Portals/0/TreesAreGood_Avoid%20Damage%20During%20Construction_0721.pdf) (read October 17, 2026)
- [Call 811: Know what's below](https://www.call811.com/) (read October 1, 2026)

### Talk to the office

[775.232.8243](tel:775.232.8243)

| Monday to Friday | 8:30 am - 5:00 pm |
|---|---|
| Saturday and Sunday | Office closed, phones answered |

Phones answered seven days a week. 24-hour emergency service.

[Free estimate](#quote)

### Keep reading

- [Arborist glossary](https://battleborntreeservice.com/glossary/)
- [Tree roots, sidewalks and sewer lines](https://battleborntreeservice.com/guides/tree-roots-sidewalks-sewer-lines/)
- [Root barriers: when they work](https://battleborntreeservice.com/guides/do-root-barriers-work/)
- [Root barriers](https://battleborntreeservice.com/tree-services/root-barriers/)

## See also

[Root flare](https://battleborntreeservice.com/glossary/root-flare/) [Structural root zone](https://battleborntreeservice.com/glossary/structural-root-zone/) [Root pruning](https://battleborntreeservice.com/glossary/root-pruning/) [Root heave](https://battleborntreeservice.com/glossary/root-heave/)