Invasive plant species are ranked according to the harm they cause, with category 1 being the most difficult to remove plants, and the ones that have the most negative effect on their new, non-native environment.
Unfortunately, many non-native invasive plants can be found in Henderson Park. You may have some on your property as well. If your landscape contains any of these plants, work to remove as many as possible, starting with category 1 plants.
The easiest way to get rid of invasive plants is never to plant them in the first place! Do NOT add to your landscape any of the plants on the following list of invasive plants. Many nurseries and big box stores still carry invasive plants, so be informed and be on your guard.
Top Non-Native Invasive Plants in Henderson Park
Evergreen:
· Privet (Ligustrum sinense) category 1
· English Ivy (Hedera helix) category 1
· Thorny Olive & Autumn Olive (Elaeagnus pungens & umbellata) category 1
· Periwinkle (Vinca minor) category 2
· Nandina (Nandina domestica) category 2
· Monkey grass (Liriope muscari) category 3
· Leatherleaf mahonia (mahonia bealei) category 3
· Chinese holly (Ilex cornuta) category 4 (isolated specimens in Henderson Park)
Deciduous:
· Chinese wisteria (Wisteria sinensis) category 1
· Japanese honeysuckle (Lonicera japonica) category 1
· Kudzu (Pueraria montana) category 1
· Japanese stilt grass (Microstegium vimineum) category 1
· Mimosa tree (Albizia julibrissin) category 1
· Bradford pear (Pyrus calleryana) category 1 (Isolated specimens in Henderson Park)
· Japanese chaff (Achyranthes japonica) category 1 alert status
· Rose of Sharon (Hibiscus syriacus) category 3
NOTE: As Master Gardeners who volunteer at Henderson Park, we always recommend removing invasive plants with mechanical removal (hand pulling or digging up) rather than chemical removal. Using herbicides should always be a last resort. None of these invasive species are easy to eradicate, regardless of the method used. It could take multiple seasons to completely eliminate these plants from a landscape.
The following section is a catalog of invasive plants found in Henderson Park, with directions for how to remove them, and suggested native alternative plants to replace them.
EVERGREEN NON-NATIVE INVASIVE PLANTS
Privet (Ligustrum sinense)
Privet forms dense thickets which prevent beneficial native plants and trees from growing.
How to remove privet:
Pull out by roots when small or young (easier after rain).
Use a privet puller for large shrubs.
Cut down privet and immediately brush the cut stump with triclopyr (i.e., Stump Out Brush and Stump Killer by Bonide).
ALL CHEMICAL TREATMENTS CAN BE DANGEROUS. READ DIRECTIONS CAREFULLY. THE LABEL IS THE LAW!
Native alternatives to replace privet:
Southern Wax Myrtle Morella cerifera (evergreen, sun to part sun)
Spicebush Lindera benzoin (deciduous, sun to shade)
Arrowwood Viburnum Viburnum dentatum (deciduous, sun to shade)
Blackhaw Viburnum Viburnum prunifolium (deciduous, sun to part sun)
Florida Doghobble Agarista populiforia (evergreen, part sun to shade)
Florida Anise Illicium floridanum (evergreen, shade to part sun)
English Ivy (Hedera helix)
English ivy is an aggressive spreader which climbs tree trunks, killing trees by preventing photosynthesis. The weight of ivy can cause branches to break off or whole trees to blow over in storms. Ivy harbors leaf scorch bacteria, which is harmful to many types of trees. Ivy also covers the ground, preventing beneficial plants from growing. When mature, English ivy produces berries that help it spread.
How to remove English ivy on trees:
Cut ivy vine at chest height and pull vine down from tree trunk. NEVER pull down ivy from higher than chest height!
Discard vines in trash.
How to remove English ivy from ground:
Pull up ivy by the roots and discard in trash.
If possible, mow to the ground new growth as it appears.
(Note: chemical removal is generally ineffective and best left to professionals.)
Native ground covers to replace English ivy:
Creeping Phlox Phlox subulata (evergreen, sun to part sun)
Green and Gold Chrysogonum virginianum (evergreen, part sun)
Foam Flower Tiarella cordifolia (evergreen, part sun to shade)
American Coral Bells Heuchera americana (evergreen, part sun to shade)
Allegheny Spurge Pachysandra procumbens (evergreen, part sun to shade)
Native vines to replace English ivy:
Trumpet Honeysuckle Lonicera sempervirens (deciduous, sun to part shade)
American Wisteria Wisteria frutescens (deciduous, sun to shade)
Crossvine Bignonia capreolata (evergreen, sun to shade)
Autumn Olive & Thorny Olive
(Elaeagnus umbellata & E. pungens)
Elaeagnus varieties are fast-growing shrubs which form dense thickets, crowding out other plants and disrupting wildlife habitats. Autumn Olive is semi-evergreen; Thorny Olive and other varieties of Elaeagnus are evergreen.
How to get rid of Elaeagnus:
Do NOT plant any variety of Elaeagnus.
Pull out by roots when small or young (easier after rain).
Dig up small shrubs.
Cut down large shrubs and immediately brush cut stump with triclopyr or glysophate (i.e., Stump Out Brush and Stump Killer by Bonide or RoundUp, KleenUp, or KillzAll).
ALL CHEMICAL TREATMENTS CAN BE DANGEROUS. READ DIRECTIONS CAREFULLY. THE LABEL IS THE LAW!
Native alternatives to replace Elaeagnus varieties:
Southern Wax Myrtle Morella cerifera (evergreen, sun to part sun)
Spicebush Lindera benzoin (deciduous, sun to shade)
Arrowwood Viburnum Viburnum dentatum (deciduous, sun to shade)
Blackhaw Viburnum Viburnum prunifolium (deciduous, sun to part sun)
Florida Doghobble Agarista populiforia (evergreen, part sun to shade)
Florida Anise Illicium floridanum (evergreen, shade to part sun)
Periwinkle (Vinca minor)
Periwinkle is an evergreen ground cover that spreads aggressively by rooting where stems touch the ground. It crowds out desirable native plants.
How to remove periwinkle:
Pull up vines by the roots and discard into the trash.
Dig up matted roots and discard.
Continue to monitor area and pull up new growth as it appears.
As a last resort on recurring growth, carefully use glysophate (i.e., RoundUp) on new leaves only.
ALL CHEMICAL TREATMENTS CAN BE DANGEROUS. READ DIRECTIONS CAREFULLY. THE LABEL IS THE LAW!
Native ground covers to replace periwinkle:
Creeping Phlox Phlox subulata (evergreen, sun to part sun)
Green and Gold Chrysogonum virginianum (semi-evergreen, part sun)
Foam Flower Tiarella cordifolia (semi-evergreen, part sun to shade)
American Coral Bells Heuchera americana (semi-evergreen, part sun to shade)
Allegheny Spurge Pachysandra procumbens (semi-evergreen, part sun to shade)
Nandina (Nandina domestica)
Birds that feed on winter fruit can be poisoned by the cyanide and alkaloids in nandina berries. Birds also drop the berries which take root and form dense thickets, choking out native plants.
How to remove nandina:
Pull out by roots when small (easiest after rain).
Dig up plants –all roots must be removed or plants will resprout.
Cut down trunks and spray the cuts with imazapyr (i.e., Ortho Groundclear).
Only between August and October, foliage may carefully be sprayed with glysophate (i.e., Round-Up).
ALL CHEMICAL TREATMENTS CAN BE DANGEROUS. READ DIRECTIONS CAREFULLY. THE LABEL IS THE LAW!
Native alternatives to nandina:
Inkberry Ilex glabra (evergreen, sun to part sun)
Yaupon Holly Ilex vomitoria (evergreen, sun to part sun)
Florida Doghobble Agarista populifolia (evergreen, part sun to shade)
Fetterbush Leucothoe fontanesiana (evergreen, part sun to shade)
American Beautyberry Callicarpa americana (deciduous, sun to part shade)
Carolina Allspice Calycanthus floridus (deciduous, sun to part shade)
Strawberry Bush Euonymous americanus (deciduous, part sun)
Oakleaf Hydrangea Hydrangea quercifolia (deciduous, part sun)
Summersweet Clethra alnifolia (deciduous, sun to shade)
Virginia Sweetspire Itea virginica (deciduous, sun to shade)
Monkey Grass aka Lilyturf (Liriope muscari)
Monkey grass spreads tenaciously by rhizomes and by berries. It crowds out desirable native plants.
How to get rid of monkey grass:
Use a shovel to dig up the roots, taking care to get them all. Discard clumps in the trash.
Watch for new sprouts and dig them up as they occur.
As a last resort, use a product containing dicamba 2,4-D herbicide (i.e., Ortho WeedClear) on new sprouts.
ALL CHEMICAL TREATMENTS CAN BE DANGEROUS. READ DIRECTIONS CAREFULLY. THE LABEL IS THE LAW!
Native grass-like groundcovers to replace monkey grass:
Pennsylvania Sedge Carex pennsylvanica (evergreen; shade to part shade)
Cherokee Sedge Carex cherokeensis (semi-evergreen; part shade)
Little Bluestem Schizachyrium scoparium (semi-evergreen; sun to shade)
Blue-eyed Grass Sisyrinchium augustifolium (evergreen; sun to part sun)
Leatherleaf Mahonia (Mahonia bealei)
Mahonia is an evergreen shrub which spreads by suckering and by seed dispersal.
How to get rid of Mahonia:
Pull out by roots when small or young (easier after rain).
Cut down and carefully spray stumps with glysophate (i.e., RoundUp, KleenUp, or KillzAll).
ALL CHEMICAL TREATMENTS CAN BE DANGEROUS. READ DIRECTIONS CAREFULLY. THE LABEL IS THE LAW!
Native alternatives to replace Mahonia:
Anise Illicium parviflorum & I. floridanum (evergreen, part sun to shade)
Florida Leucothoe Agarista populifolia (evergreen, part sun to shade)
Native Viburnums Viburnum dentatum, V. prunifolium, V. nudum (deciduous, part sun)
DECIDUOUS NON-NATIVE INVASIVE PLANTS
Chinese Wisteria (Wisteria sinensis) &
Japanese Wisteria (Wisteria floribunda)
Chinese and Japanese wisterias are nearly indistinguishable. They both grow rapidly, girdling and choking trees. The heavy weight of the vines can pull down tree limbs and any structure (such as an arbor) supporting them. They also smother desirable plants on the ground. Wisterias spread by seeds and by vine runners, rooting where covered by leaves.
How to get rid of Chinese and Japanese wisteria:
Do NOT plant! Wisterias are difficult to control and to remove when out of control.
Pull up new sprouts when small, making sure to get all roots and discard into trash.
Unwind vines from around trees, if possible, and pull out by the roots. NEVER pull down vines from higher than chest height. Discard vines into trash.
Chemical removal is best left to professionals. However, homeowners may try cutting vines and carefully brushing cuts with glysophate (i.e., Round-Up) between the months of May and October. This likely will take repeated treatments.
ALL CHEMICAL TREATMENTS CAN BE DANGEROUS. READ DIRECTIONS CAREFULLY. THE LABEL IS THE LAW!
Native alternatives to Chinese and Japanese wisteria:
American wisteria Wisteria frutescens ‘Amethyst Falls’ (deciduous, sun to shade)
Trumpet honeysuckle Lonicera semperivirens (evergreen, full sun)
Dutchman’s pipe Aristolochia macrophylla (deciduous, sun to part shade)
Crossvine Bignonia capreolata (evergreen, sun to shade)
Japanese honeysuckle (Lonicera japonica)
Japanese honeysuckle spreads aggressively, forming a dense mat along the ground, girdling saplings and climbing trees, forming a canopy which shades desirable native trees and plants.
How to remove Japanese honeysuckle:
Unwind from around trees and pull roots from ground.
Cut at ground level and brush cuts with a product containing triclopyr (i.e., Stump Out Brush and Stump Killer by Bonide).
ALL CHEMICAL TREATMENTS CAN BE DANGEROUS. READ DIRECTIONS CAREFULLY. THE LABEL IS THE LAW!
Native alternatives to replace Japanese honeysuckle:
Carolina Jasmine Gelsemium sempervirens (evergreen, sun to part sun)
Trumpet Honeysuckle Lonicera sempervirens (deciduous, sun to part sun)
Crossvine Bignonia capreolata (evergreen, sun to shade)
Kudzu (Pueraria montana)
Kudzu is a vine that grows rapidly - up to a foot per day - climbing trees and smothering everything in its path. It spreads by seeds and by stems rooting along the ground.
How to get rid of Kudzu:
Cut back vines to the ground as new growth appears. This method will take several seasons to eradicate kudzu.
Vines may be cut and removed, and the area covered with heavy plastic.
For smaller infestations, repeatedly spray foliage over the growing season with an herbicide recommended for removal of poison ivy.
Large vines may be cut at the ground and carefully brushed with an herbicide containing triclopyr (i.e., Stump Out Brush and Stump Killer by Bonide).
ALL CHEMICAL TREATMENTS CAN BE DANGEROUS. READ DIRECTIONS CAREFULLY. THE LABEL IS THE LAW!
Native alternatives to replace kudzu:
Carolina Jasmine Gelsemium sempervirens (evergreen, sun to part sun)
Trumpet Honeysuckle Lonicera sempervirens (deciduous, sun to part sun)
Crossvine Bignonia capreolata (evergreen, sun to shade)
Japanese Stiltgrass aka Nepalese Browntop (Microstegium vimineum)
Stiltgrass is a shade-loving annual grass that aggressively spreads via seeds to blanket the ground, crowding out desirable native plants.
How to get rid of stiltgrass:
Mow it down or pull it up by the roots in the summer before it sets seeds in early fall. This is easily done after rain. Because stiltgrass produces so many seeds that can remain viable in the soil for years, it may take several seasons to completely eradicate it.
Native alternatives to replace stiltgrass:
Pennsylvania Sedge Carex pennsylvanica (evergreen; shade to part shade)
Cherokee Sedge Carex cherokeensis (semi-evergreen; part shade)
Little Bluestem Schizachyrium scoparium (semi-evergreen; sun to shade)
Christmas Fern Polystichum acrostichoides (semi-evergreen; shade)
Native Wood Ferns (NOT Autumn Ferns) Dryopteris varieties (deciduous; shade)
Mimosa Tree (Albizia julibrissin)
Mimosa trees are weak-limbed, disease-prone, aggressive growers which outcompete native plants. They spread by underground roots and numerous seeds. The seeds may remain viable for years.
How to get rid of Mimosa trees:
Cut tree down and immediately brush cut stump with triclopyr (i.e., Stump Out Brush and Stump Killer by Bonide)
ALL CHEMICAL TREATMENTS CAN BE DANGEROUS. READ DIRECTIONS CAREFULLY. THE LABEL IS THE LAW!
Native alternatives to replace Mimosa trees:
Rose Locust Robinia hispida (full sun)
Elderberry Sambucus varieties (full sun)
Buckeye Aesculus varieties (full sun to part sun)
Bradford Pear (Pyrus calleryana)
Bradford pears are rapidly growing trees which colonize as thickets, crowding out desirable trees and plants. They pose hazards to homeowners due to weak limbs prone to breaking, and tough thorns. They have no value to any insect or wildlife.
How to get rid of Bradford pears:
Do NOT plant these trees. (Several states now ban sales of Bradford pear trees.)
Cut the trees down, and either grind up the stump or immediately brush the cut stump with triclopyr (i.e., Stump Out Brush and Stump Killer by Bonide) or glysophate (i.e., RoundUp, KleenUp, or KillzAll).
ALL CHEMICAL TREATMENTS CAN BE DANGEROUS. READ DIRECTIONS CAREFULLY. THE LABEL IS THE LAW!
Native alternatives to replace Bradford pears:
Dogwood Cornus florida (part shade)
Redbud Cercis canadensis (part shade)
Serviceberry Amelanchier varieties (sun to part shade)
Fringetree Chionanthus virginicus (sun to part shade)
Black Cherry Prunus serotina (sun)
Japanese Chaff (Achyranthes japonica)
Japanese chaff is a relatively recent threat to habitats. It spreads rapidly by producing many seeds per plant. Seeds are distributed by flowing water or by traveling on people, pets, or wild animals. Chaff is a shade-loving plant that outcompetes native plants due to its dense growth.
How to get rid of Japanese chaff:
Pull it up by the roots in the summer before it sets seeds in late summer. This is easily done after rain. Bag plants and discard them in the trash. Check your clothes for seeds! Because Japanese chaff produces so many seeds that can remain viable in the soil for years, it may take several seasons to completely eradicate it.
Native alternatives to replace Japanese chaff:
Pennsylvania Sedge Carex pennsylvanica (evergreen; shade to part shade)
Cherokee Sedge Carex cherokeensis (semi-evergreen; part shade)
Little Bluestem Schizachyrium scoparium (semi-evergreen; sun to shade)
Christmas Fern Polystichum acrostichoides (semi-evergreen; shade)
Native Wood Ferns (NOT Autumn Ferns) Dryopteris varieties (deciduous; shade)
Rose of Sharon (Hibiscus syriacus)
Rose of Sharon is an aggressive growing shrub that spreads via seeds and has a deep root system.
How to get rid of Rose of Sharon:
Pull out by roots when small or young (easier after rain).
Dig up small shrubs, taking care to get all of the roots.
New foliage may be carefully sprayed with glysophate (i.e., RoundUp, KleenUp, KillzAll).
ALL CHEMICAL TREATMENTS CAN BE DANGEROUS. READ DIRECTIONS CAREFULLY. THE LABEL IS THE LAW!
Native alternatives to replace Rose of Sharon:
Rose Mallows: Hibiscus moscheutos, H. coccineus, or H. laevis (deciduous, sun to part sun)
References:
https://www.eddmaps.org good general info website
https://www.invasive.org source of ID photos
https://blogs.ifas.ufl.edu/caip/2022/05/10/how-long-until-a-new-species-becomes-invasive-lets-talk-about-the-lag-phase/ explanation of why it takes years for an exotic to become invasive
explanation of difference between invasive and aggressive plants