The 10 Worst Invasive Plants in Michigan (and How to Actually Get Rid of Them)
The Gibson Environmental Services crew
More than 10 years clearing land, cutting trails, and running forestry equipment in Southeast Michigan.
Walk the edge of almost any lot in Oakland, Macomb, Livingston, or Lapeer County and you will find the same handful of plants doing the damage: buckthorn walling off the woods, honeysuckle under every tree, autumn olive taking the old field, and a vine or two pulling down the fence line. They came from nurseries and windbreaks decades ago, birds spread the seed, and nothing here eats them.
This guide covers the ten invasive plants we clear most often in Southeast Michigan, how to tell them apart, and what it actually takes to get rid of each one. Gibson Environmental Services does the mechanical part: a tracked forestry mulcher that grinds the whole stand, roots left in place, in a day. The follow-up is where most people lose, so each entry says what to expect the season after.
The Ten, Roughly in the Order We See Them
1. Common Buckthorn and Glossy Buckthorn
Rhamnus cathartica, Frangula alnus
How to spot it: A shrub or small tree to 20 feet with dark, oval, finely toothed leaves that stay green into November after everything else has dropped. Black berries in clusters, a thorn at the tip of many twigs on common buckthorn, and a shiny, untoothed leaf on glossy buckthorn, which prefers wet ground.
Why it is a problem: It leafs out first and holds on last, so nothing grows under it. In ten years it turns an open woodlot into a dark thicket with bare dirt below, and the berries feed a seed bank that keeps producing seedlings for years.
How to get rid of it: Mulch the stand to the ground. Buckthorn resprouts from the stump, so plan on a cut-stump treatment or two seasons of mowing on the resprouts, and expect seedlings from the seed bank that the mulch layer will smother most of. Our buckthorn and autumn olive guide goes deeper.
2. Autumn Olive
Elaeagnus umbellata
How to spot it: A sprawling shrub to 20 feet with silvery, scaly undersides on the leaves, small thorns, and speckled red berries in September and October. Loves old fields, fencerows, and the sandy ground of Lapeer County and northern Oakland.
Why it is a problem: It makes its own nitrogen, so it thrives on poor soil where nothing else will, and one shrub becomes an acre in a few years of bird traffic.
How to get rid of it: Mulching handles even the biggest thickets in a pass. It resprouts hard, so the stumps need a cut-stump treatment or repeated mowing the following year.
3. Bush Honeysuckle
Lonicera maackii, L. morrowii, L. tatarica
How to spot it: A multi-stemmed shrub 6 to 15 feet tall with opposite leaves, hollow older stems, white to pink flowers in May, and red or orange berries by late summer. The first shrub to leaf out in spring and the understory in most Metro Detroit woodlots.
Why it is a problem: It shades out every wildflower and tree seedling below it and gives birds a poor-nutrition berry that does not carry them through winter.
How to get rid of it: Easy, as invasives go. Shallow roots mean small plants pull, and a mulcher takes out the wall of it in one pass. Resprouting is lighter than buckthorn, but check the stumps the next summer.
4. Multiflora Rose
Rosa multiflora
How to spot it: Long, arching, thorny canes to 15 feet that root wherever the tip touches the ground, clusters of small white flowers in June, and red hips in fall. Old pastures, fence lines, and trail edges.
Why it is a problem: It builds thickets nothing can walk through, ties up fence lines, and spreads by both seed and rooting canes, so it advances on two fronts.
How to get rid of it: Mulch the thicket, then mow the regrowth the following season so the rooted cane tips do not restart it. Brush hogging works on the open-field portions once the big canes are gone.
5. Oriental Bittersweet
Celastrus orbiculatus
How to spot it: A woody vine with round, glossy leaves, orange roots, and yellow capsules that split to show red berries in fall. It climbs 60 feet and can grow thicker than your wrist.
Why it is a problem: It strangles the trunk it climbs and loads the crown until the tree comes down. Fence lines and woodlot edges go first.
How to get rid of it: Cut the vines at chest height and at the ground, mulch the ground layer, and treat the cut stumps, because the roots resprout. Any vine left attached to a tree will keep growing.
6. Japanese Barberry
Berberis thunbergii
How to spot it: A low, spiny shrub, usually two to four feet, with small spoon-shaped leaves, single thorns at each leaf node, and bright red berries that hang on through winter. Escaped from landscaping into shaded woods.
Why it is a problem: It tolerates deep shade, so it fills the woods floor, and dense barberry holds humidity that ticks love. Properties with barberry carry more ticks.
How to get rid of it: Shallow roots. Small plants pull, big stands mulch or mow, and the mulch layer keeps most of the seedlings down. Wear leather gloves.
7. Callery (Bradford) Pear
Pyrus calleryana
How to spot it: The white-flowering street tree, now growing wild along roads, in old fields, and on new-construction edges. Wild seedlings carry long thorns, and the flowers in April smell like something died.
Why it is a problem: Escaped pears form dense thorny thickets in a few years, crowd out everything, and feed almost nothing.
How to get rid of it: Mulch the thicket, then treat or mow the resprouts, because it comes back from the stump.
8. Tree of Heaven
Ailanthus altissima
How to spot it: A fast, smooth-barked tree to 70 feet with long compound leaves, a peanut-butter smell when crushed, and tan seed clusters on the female trees. Road edges, rail lines, and disturbed ground.
Why it is a problem: It suckers from the roots across a whole lot, and it is the preferred host of the spotted lanternfly, which has been confirmed in Michigan.
How to get rid of it: Cutting it alone makes it worse; each cut stump throws up dozens of root suckers. Treat it while it is standing, wait for the top to die, then mulch the dead stems and suckers. This one is a planned two-step job, not a single pass.
9. Japanese Knotweed
Reynoutria japonica
How to spot it: Bamboo-like hollow stems 8 to 15 feet tall with heart-shaped leaves and sprays of tiny white flowers in late summer. Stream banks, ditches, and the edges of older neighborhoods.
Why it is a problem: The rhizomes run deep and wide, push through pavement and foundations, and a piece the size of a fingernail starts a new stand.
How to get rid of it: No machine kills knotweed in a day. Mowing or mulching the stand in late summer knocks it down and thins it, but the rhizome comes back, so it is the first step of a multi-year plan with treatment on the regrowth. Every bit of cut material stays on site, never hauled, never chipped into the fill pile.
10. Phragmites (Common Reed)
Phragmites australis
How to spot it: Reeds 10 to 15 feet tall with feathery purple-brown plumes, in stands so thick you cannot see through them. Pond shores, ditches, retention basins, and wet corners of fields.
Why it is a problem: It replaces every other wetland plant, dries into a fire hazard, and blocks the view of and access to the water.
How to get rid of it: Mow or mulch the stand in late summer or on frozen ground in winter to remove the thatch, then treat the regrowth. Like knotweed, one cut is a start, not a finish, and the second year is where you win.
Honorable Mentions
- Garlic mustard. The knee-high herb with the white flowers and garlic smell; hand-pull before it seeds, no machine needed.
- Purple loosestrife. The magenta spikes in every wet ditch; a wetland problem, not a brush-clearing one.
- Black locust. Thorny, fast, and it suckers like tree of heaven; treat first, then mulch.
- Norway maple. The yard tree that seeds the woods with a canopy nothing grows under; the seedlings and saplings it throws mulch easily.
- Privet. Old hedge plants gone wild along fence lines; mulches easily, resprouts lightly.
Which Method for Which Plant
| Plant | First step | Follow-up | Seasons to finish |
|---|---|---|---|
| Buckthorn | Mulch the stand | Cut-stump treatment or mowing on resprouts | 2 to 3 |
| Autumn olive | Mulch the stand | Treat or mow resprouts | 2 |
| Bush honeysuckle | Mulch; pull small plants | Check stumps next summer | 1 to 2 |
| Multiflora rose | Mulch the thicket | Mow regrowth | 2 |
| Oriental bittersweet | Cut vines high and low, mulch ground layer | Treat stumps | 2 |
| Japanese barberry | Mulch or mow; pull small plants | Mulch layer handles most seedlings | 1 to 2 |
| Callery pear | Mulch the thicket | Treat or mow resprouts | 2 |
| Tree of heaven | Treat standing, then mulch | Watch for suckers | 2 to 3 |
| Japanese knotweed | Mow or mulch late summer | Treat regrowth every year | 3 or more |
| Phragmites | Mow or mulch late summer or on frozen ground | Treat regrowth | 2 to 3 |
The pattern is the same for all ten: the machine removes years of growth in a day, the mulch layer smothers the seedlings, and a light follow-up on the resprouts the next season finishes what the first pass started. Skipping the follow-up is how a cleared lot becomes a thicket again.
When to Clear Invasives in Michigan
October and November are the best months for buckthorn, honeysuckle, and autumn olive. They hold their leaves weeks after the native trees drop theirs, so the invasive brush is the only green in the woods and the natives are easy to leave standing.
Winter on frozen ground is the time for phragmites, wet edges, and pond shores that would rut in summer, and for vines, which are easy to trace with the leaves down.
Spring and summer are fine for fields, fence lines, and dry woods. The only thing we avoid is the wettest ground in April.
If the lot is also a hunting property, the same fall visit can open the trails and shooting lanes and clear ground for a food plot; the invasives at the edges are usually what has been closing them in.
What Clearing Invasives Costs
We quote a fixed project price based on acreage and how dense the growth is. A woodlot understory of honeysuckle and barberry is the light end of the work; a wall of mature buckthorn and autumn olive with everything tangled in bittersweet is the heavy end, and our pricing guide explains what moves the number. Either way the number is final before we start, and the invasive growth removal page covers what the day on site looks like.
Common Questions
Will the invasives grow back after mulching?
Some will try. Buckthorn, autumn olive, and honeysuckle resprout from the stump, and there is a seed bank in the soil from years of berries. The mulch layer smothers most of the seedlings, and one or two seasons of mowing or a cut-stump treatment on the resprouts finishes the job. What does not come back is the six-foot wall of brush, because the roots never get the chance to rebuild it.
Can you tell me what I have from photos?
Usually, yes. Leaf shape, thorns, berries, and the stem all give it away, and a few phone photos are enough to price the job. If you are not sure, take one of the leaves, one of the berries or flowers, and one of the whole plant with something for scale.
Is mulching better than spraying?
They do different jobs. Mulching removes the standing brush, saplings, and thatch in a day and leaves the ground covered, which is the part no sprayer can do. Spot-treating the resprouts afterward is how you keep it from coming back. On most properties the two together beat either one alone.
What is the best time of year to clear invasives?
Fall. Buckthorn and honeysuckle hold their leaves weeks after the native trees drop theirs, so in October and November the invasive brush is the only green in the woods and easy to take out cleanly. Frozen ground in winter is the time for wet edges and phragmites, and spring is fine for everything except the wettest ground.
Where We Do This Work
The work in this guide is done across eight Southeast Michigan counties from our base in Royal Oak. Every county page lists the townships we work in most, with a page for each.
Losing Ground to Buckthorn, Honeysuckle, or Autumn Olive?
Send a few photos of the growth and the address. We will tell you what it is, quote the clearing as one project, and tell you what to expect the season after.