There's a good chance you have at least one of these trees on your property — and an equally good chance you've never thought twice about it.

That's not a criticism. These trees didn't earn their reputation as problems overnight, and most of them were actually sold at nurseries and planted intentionally for decades. Some of them are genuinely beautiful. A few of them probably bring back fond memories. But all of them share a common problem: they spread aggressively, crowd out native plants, and can quietly take over a yard — or a whole neighborhood — without anyone noticing until the damage is done.

The Chattanooga area is particularly susceptible to invasive trees because our climate is practically ideal for them — long growing seasons, regular rainfall, mild winters, and plenty of disturbed soil along roadsides and property edges where these species love to get a foothold.

Here's a look at four of the most common invasive trees in our area, how to identify them, what they're doing to your yard and the surrounding ecosystem, and what you can do about them.

Bradford Pear: The Pretty One With a Bad Reputation

If you've been in Chattanooga in late February or early March, you know this tree. It's the one that seems to explode in white blossoms practically overnight, lining roadsides and suburban yards with what looks like a postcard from spring. For a long time, it was considered a nearly perfect landscaping tree.

That assessment has been revised significantly.

Bradford pears — technically Callery pears (Pyrus calleryana) — are now listed as an "established invasive threat" by the Tennessee Invasive Plant Council. The City of Chattanooga stopped planting them in public landscaping back in 2017. Several other states have gone further and banned their sale altogether. Tennessee is actively discussing similar measures.

How to spot one: White blossoms in late winter or very early spring, often before most other trees have leafed out. Glossy oval leaves in summer, reddish-purple fall color. Upright pyramidal shape when young. The flowers have a famously unpleasant smell up close.

Why it's a problem: The original Bradford cultivar was thought to be sterile, which is part of why it became so popular. What wasn't understood at the time is that when different Callery pear cultivars cross-pollinate with each other — which happens easily when multiple trees are planted in proximity — the offspring are very much not sterile. Birds spread those seeds widely, and the resulting wild seedlings revert to a thorny, aggressive form that creates dense thickets in fields and forest edges, crowding out native plants. The trees also have notoriously weak branch structure and tend to split dramatically in storms, which is a separate headache for homeowners.

What to do: If you have a Bradford pear and want to remove it, now is actually a good time — late winter, while it's still dormant. Cut stumps should be treated to prevent resprouting. Good native alternatives with similar spring bloom appeal include flowering dogwood, Eastern redbud, and serviceberry.

Mimosa: The One That Looks Like It Belongs in a Painting

Mimosa trees (Albizia julibrissin) are the kind of tree that makes people nostalgic. Feathery, fern-like leaves. Soft pink powder-puff flowers in summer. A tropical feel that seems almost out of place in a Tennessee yard — which is exactly why people have been planting them here since the 1700s.

Chattanooga's city forester has described the mimosa as "very attractive" with a quality that makes it easy to understand why homeowners love it. But he's also called it "a very invasive tree that takes over native ecosystems."

Both things are true.

How to spot one: Distinctive fern-like compound leaves that fold up at night or when touched. Showy pink, fluffy flowers in early to midsummer. Flat seed pods that look like dried pea pods. Often multi-trunked. Usually 20–40 feet tall.

Why it's a problem: Mimosas spread prolifically by seed, and those seeds can remain viable in the soil for years. They establish quickly in disturbed areas, roadsides, and forest edges — exactly the kinds of spots that are common along property lines and fence rows in suburban Chattanooga. Once established, they outcompete native trees for sunlight and nutrients, and their dense canopy shades out the plants below them for an extended season since they leaf out early and drop their leaves late.

What to do: Smaller mimosas can sometimes be pulled or cut, but the root system is persistent — stumps need to be treated to prevent regrowth. For larger trees, removal is the most reliable option. Native alternatives with similar summer flower appeal include native azaleas and Eastern redbud.

Tree of Heaven: The One That Smells Wrong

Tree of Heaven (Ailanthus altissima) doesn't have the nostalgic charm of a mimosa or the spring beauty of a Bradford pear. What it has is an extraordinary ability to grow absolutely anywhere — sidewalk cracks, fence lines, the back corner of a neglected lot — and a distinctive unpleasant smell that gives it away once you know what to look for.

UT Extension has called it the most prevalent invasive plant problem for trees in the state of Tennessee. It's also the favored host of the Spotted Lanternfly, an invasive pest that Tennessee agriculture officials are actively working to contain.

How to spot one: Large compound leaves — sometimes two feet long — with 10 to 40 leaflets that have a smooth edge except for a small notch near the base. The leaves and crushed stems have a strong, unpleasant smell often described as burnt peanut butter or rancid nuts. Clusters of yellowish-green flowers in summer, followed by papery winged seeds. Grows extremely fast, often in places where nothing else seems to want to grow.

Why it's a problem: Tree of Heaven is remarkably difficult to get rid of once established. It spreads both by seed and by root sprouts, meaning cutting it down without treating the stump and roots often results in an even denser cluster of growth coming back. The root system can damage sewer lines and foundations, and the tree produces chemicals that inhibit the growth of nearby plants. Beyond the property-level concerns, its role as a host for Spotted Lanternfly makes containing its spread a regional agricultural priority.

What to do: This one genuinely benefits from professional removal. Because of its tendency to resprout aggressively, improper removal can make the situation worse. A complete removal with stump grinding and root treatment gives you the best chance of actually being done with it.

Princess Tree: The Fast One Nobody Planted on Purpose

The princess tree (Paulownia tomentosa) is one you may have noticed without knowing its name. It grows startlingly fast — sometimes 10 to 15 feet in a single season — and produces showy purple flowers in spring that make it look like something you'd see in a botanical garden. A single mature tree can produce up to 20 million seeds annually, each one light enough to travel miles on the wind.

That combination of rapid growth and prolific seeding is exactly why it has become such a significant invasive concern across Tennessee and the broader Southeast.

How to spot one: Very large heart-shaped leaves — sometimes a foot or more across on young trees. Showy purple, trumpet-shaped flowers in spring, before the leaves emerge. Rounded, woody seed pods that persist through winter. Grows quickly to 30–60 feet with a broad, spreading canopy.

Why it's a problem: Princess trees establish readily on roadsides, forest edges, and disturbed areas, growing fast enough to outshade native seedlings before they have a chance to establish. Their seeds travel widely, meaning a single tree can generate new infestations far beyond your property line. In some Tennessee counties, property owners can face fines for allowing them to spread.

What to do: Young seedlings can be pulled when the soil is moist. Larger trees warrant professional removal, with stump treatment to prevent resprouting. Native alternatives with similar spring flowering appeal include tulip poplar, native magnolias, and flowering dogwood.

A Note on Timing

If you've recognized any of these trees in your yard, late winter and early spring is actually a useful window to act. Many of these species are easier to identify right now — before everything leafs out — and removal during dormancy tends to be cleaner and less disruptive to the surrounding landscape.

It's also worth mentioning that removing an invasive tree doesn't have to mean losing the shade, the privacy, or the visual appeal that tree was providing. There are excellent native alternatives for all of these species that will serve your yard better in the long run — and won't be quietly spreading into your neighbor's yard or the green space down the road.

Not Sure What You're Looking At?

If you've got a tree you can't identify, or one you suspect might be on this list, we're happy to come take a look. We work in yards across the greater Chattanooga area and North Georgia, and we can give you a straight answer on what you've got and what — if anything — makes sense to do about it.

Give us a call or text at (423) 443-4533 anytime.