⚠️ Zone 6a · Kansas City

Invasive Species

The state-listed noxious weeds you're legally required to control, plus the popular ornamental plants escaping out of KC gardens into our remaining woodlands and prairies. Every one has a better native alternative.

⚠️ Why This Matters

Invasive plants displace natives that feed our pollinators and birds, monopolize woodland understories, and quietly destroy the prairie remnants that surround KC. The worst of them spread from suburban yards into public lands faster than anyone can pull them.

💡 What "invasive" actually means: a non-native plant that spreads aggressively beyond where it was planted, causes ecological harm, and outcompetes native species. Not every non-native plant is invasive — tomatoes and apples are non-native too. The problem is the ones that escape cultivation and take over.

🚨 Kansas State-Listed Noxious Weeds

The official Kansas Department of Agriculture list. State law (K.S.A. 2-1313a) requires all landowners to control and eradicate these on their property. Most show up on rural land, but garden compost and birdseed can introduce them anywhere.

Not widely established — targeted for full eradication.

Present in some areas — controlled to prevent spread.

Widespread — managed to reduce impact over time.

Category A — Eradication Targets

Hoary Cress

Lepidium draba

Perennial mustard-family forb from Eurasia. Spreads aggressively by extensive rhizomes — a single plant can colonize huge areas. White 4-petaled flowers May–July, distinctive flattened heart-shaped seed pods.

Leafy Spurge

Euphorbia virgata

European/Asian perennial. Creeping roots send up new shoots every few inches. Milky sap (skin irritant). Seeds eject explosively up to 20 ft. One of the most economically damaging weeds on Kansas grazing land.

Quackgrass

Elymus repens

Cool-season perennial grass from Eurasia. Pale yellow rhizomes 2–18" deep make it nearly impossible to dig out — every fragment becomes a new plant. Often comes in as contamination in hay or seed.

Russian Knapweed

Rhaponticum repens

Perennial Asian forb. Reproduces by roots, rhizomes, and seed. Rose-to-purple flask-shaped flower heads on grey-hairy stems. Allelopathic — chemically suppresses other plants from growing nearby.

Kudzu

Pueraria montana var. lobata

"The vine that ate the South." Semi-woody vine — climbing stems reach 100 ft. Smothers everything underneath. Not yet widespread in KS, which is why it's a Category A eradication priority. Report any sighting to your county weed department.

Spotted Knapweed & Diffuse Knapweed (added May 2026)

Centaurea stoebe · C. diffusa

Aggressive prairie invaders. Pink-purple thistle-like flowers. Both species secrete allelopathic chemicals that kill surrounding native plants. Major threat to Flint Hills prairie ecosystems.

Category B — Controlled to Prevent Spread

Canada Thistle

Cirsium arvense

European perennial. Creeping white roots send up shoots every 8–12". Pink-to-purple ½–1" flower heads. Spreads by both seed and roots — small infestations become huge fast. Not actually from Canada.

Common Teasel & Cutleaf Teasel (added May 2026)

Dipsacus fullonum · D. laciniatus

Tall European biennials with spiny conical flower heads (the ones dried-flower arrangers love). A single plant can produce 2,000 seeds. Forms dense stands along roadsides and waterways, displacing natives.

Category C — Widespread, Manage Impact

Field Bindweed

Convolvulus arvensis

Eurasian twining perennial. Roots reach 20–30 ft deep — the reason this plant is "manage impact" rather than "eradicate." White or pink funnel-shaped flowers. Every KC gardener will encounter this in their lifetime.

Musk Thistle

Carduus nutans

Eurasian biennial. Large nodding purple flower heads. The earliest blooming thistle in Kansas. Each plant produces 10,000+ wind-dispersed seeds. Hand-pulling rosettes before bolting is the most effective small-scale control.

Sericea Lespedeza

Lespedeza cuneata

Asian shrubby legume, 2–5 ft tall. Was actually planted intentionally for erosion control through the mid-1900s — a serious lesson in unintended consequences. Now dominates many Kansas grasslands.

Johnsongrass

Sorghum halepense

Warm-season perennial grass from Asia/N. Africa. Grows 6–12 ft tall. Spreads by long rhizomes and seed. Major problem in row-crop agriculture; also shows up in disturbed urban land.

Bur Ragweed

Ambrosia grayii

Native (yes, native — but extremely aggressive), 1–2 ft tall. Silvery-grey foliage. Spiny bur-like fruits attach to clothing and animal fur. The exception to the "invasive = non-native" rule.

Amur Honeysuckle (added May 2026)

Lonicera maackii

The big one for KC gardeners. Large bush honeysuckle that leafs out earlier and drops leaves later than natives, shading out the forest floor. Forms dense thickets in Swope Park, Kessler Park, and basically every KC woodlot. See garden-escapees section below for alternatives.

📋 Official source: Kansas Department of Agriculture — Noxious Weed List. Your county may have additional county-option weeds.

🪴 Common KC Garden Escapees

Plants you'll still find at most KC garden centers — and the ones most responsible for the destruction of our remaining woodlands. None of these are state-listed (yet), but all are documented invasive in the KC region.

🌳 Callery / Bradford Pear

Pyrus calleryana

The problem: Sold as "sterile" cultivars (Bradford, Cleveland Select, Chanticleer), but they cross-pollinate with other Callery cultivars and produce thorny wild offspring. The species now grows wild in over half of Kansas counties. Smells like rotting fish in spring.

Legal status: Banned in Missouri (2025). Kansas import/movement ban takes effect Jan 1, 2027.

Plant instead:

Serviceberry (Amelanchier arborea) — white spring blooms, edible summer fruit, gorgeous fall color
Eastern Redbud (Cercis canadensis) — Kansas's state tree, pink spring blooms before leaves
Wild Plum (Prunus americana) — fragrant white blooms, feeds wildlife
Black Haw Viburnum (Viburnum prunifolium) — white flower clusters, dark fruit, red fall color
Ironwood (Ostrya virginiana) — small understory tree, golden fall color

🌿 Bush Honeysuckle

Lonicera maackii, L. tatarica, L. morrowii

The problem: The single most destructive invasive plant in greater KC. Leafs out before everything else, drops leaves last, shades out every native understory plant. Berries are bright red but offer almost no nutrition — birds spread them everywhere but lose weight eating them.

Plant instead:

American Beautyberry (Callicarpa americana) — striking purple fall berries
Ninebark (Physocarpus opulifolius) — peeling bark, white flower clusters, drought-tough
Native Viburnums — arrowwood, black haw, nannyberry — every part valuable to wildlife
Spicebush (Lindera benzoin) — aromatic, host plant for spicebush swallowtail
Gray Dogwood (Cornus racemosa) — white flowers, white berries on red stems, songbird magnet

🌱 Japanese Honeysuckle (vine)

Lonicera japonica

The problem: Vining cousin of bush honeysuckle. Climbs trees, smothers shrubs, drapes over native vegetation and slowly kills it by blocking light. Fragrant flowers don't make up for the damage.

Plant instead:

Coral Honeysuckle (Lonicera sempervirens) — native, non-invasive, hummingbird favorite, gorgeous orange-red tubular flowers
Virgin's Bower (Clematis virginiana) — native clematis with masses of small white flowers
American Wisteria (Wisteria frutescens) — the native one, not the aggressive Asian wisteria

🍁 Burning Bush / Winged Euonymus

Euonymus alatus

The problem: Sold for the brilliant red fall color. Spreads aggressively into woodlands by bird-dispersed seed. Forms dense colonies that suppress native understory plants.

Plant instead:

Red Chokeberry (Aronia arbutifolia) — same brilliant red fall color, plus white spring flowers and red berries
Virginia Sweetspire (Itea virginica) — outstanding crimson fall foliage, fragrant white summer flowers
Fragrant Sumac (Rhus aromatica) — yellow-orange-red fall color, tough as nails
Native Wahoo (Euonymus atropurpureus) — the native cousin: pink-red fall color and showy red fruits

🌿 Wintercreeper

Euonymus fortunei

The problem: Evergreen vine sold as a "tough" ground cover. Climbs trees and smothers them. Birds spread the seeds widely. Major problem in Swope Park, Cave Spring Park, and along KC's wooded greenways.

Plant instead:

Allegheny Spurge (Pachysandra procumbens) — native woodland groundcover
Wild Ginger (Asarum canadense) — heart-shaped leaves, lovely woodland carpet
Foamflower (Tiarella cordifolia) — frothy white spring flowers, semi-evergreen
Pennsylvania Sedge (Carex pensylvanica) — fine-textured native sedge "lawn" alternative

🌱 English Ivy

Hedera helix

The problem: Climbing evergreen vine. Smothers trees, eventually pulling them down with weight. Forms dense ground mats that prevent native plant regeneration. Causes serious skin reactions in some people.

Plant instead:

Wild Ginger, Allegheny Spurge, Pennsylvania Sedge — same options as wintercreeper
Partridge Berry (Mitchella repens) — tiny evergreen groundcover with red winter berries

💜 Periwinkle / Vinca

Vinca minor, V. major

The problem: Sold as a "deer-resistant evergreen ground cover." Escapes garden borders aggressively, smothers woodland wildflowers, and provides almost no value to native wildlife.

Plant instead:

Wild Geranium (Geranium maculatum) — pink-purple spring flowers
Creeping Phlox (Phlox stolonifera) — native evergreen mat with spring flowers
Foamflower & Wild Ginger — same as wintercreeper alternatives

🌳 Japanese Barberry

Berberis thunbergii

The problem: Thorny shrub sold for purple foliage. Escapes into woodlands, raises forest-floor humidity, and dramatically increases tick populations — peer-reviewed research links barberry thickets to higher Lyme disease rates.

Plant instead:

Ninebark (Physocarpus opulifolius 'Summer Wine') — same dark purple foliage, native, no thorns
Black Chokeberry (Aronia melanocarpa) — white spring flowers, dark berries, red fall color
Native Sumacs — fragrant sumac, smooth sumac — tough and brilliant fall color

🌳 Tree of Heaven

Ailanthus altissima

The problem: Fast-growing Asian tree (the one from A Tree Grows in Brooklyn). Sprouts aggressively from roots — cutting it down causes dozens of new sprouts. Produces chemicals that poison surrounding plants. Primary host for spotted lanternfly, which threatens KS vineyards and orchards.

Plant instead:

Smooth Sumac (Rhus glabra) — similar growth habit, brilliant red fall color, native
Hackberry (Celtis occidentalis) — tough KC native that thrives in clay and disturbed soils
Kentucky Coffeetree (Gymnocladus dioicus) — Kansas-native large shade tree

🫒 Autumn Olive

Elaeagnus umbellata

The problem: Was planted intentionally by USDA for "wildlife habitat" through the 1970s — another lesson in unintended consequences. Silvery foliage, fragrant flowers, abundant red berries that birds spread everywhere. Nitrogen-fixing roots change soil chemistry, favoring more invasives.

Plant instead:

American Plum (Prunus americana) — fragrant white spring flowers, edible fruit, thicket-forming native
Native Crabapples (Malus ioensis, M. coronaria) — true natives, not the Asian cultivars
Serviceberry (Amelanchier arborea) — same wildlife value, far better behavior

📞 If You Find a Category A Invasive

Kudzu, knapweeds, and other Category A weeds are rare in Kansas — but spreading. Reporting a sighting helps land managers eradicate them before they get established.

Report to your County Weed Department

Wyandotte County — through the Unified Government: wycokck.org
Johnson County — Public Works Noxious Weeds: jocogov.org
Statewide — Kansas Department of Agriculture: 785-564-6700

💡 Photograph before reporting. A clear photo of the leaves, flowers, and overall habit (whole-plant view) makes identification far easier. iNaturalist's plant ID feature is shockingly good — second opinion before calling.

📝 The takeaway: when you're planning a planting, ask "what does this feed?" A serviceberry feeds 80+ species of caterpillars and a dozen birds. A Bradford pear feeds nothing. The native alternatives here aren't just "less harmful" — they're actively better for what makes a garden feel alive. For more on building native landscapes, see the Native Plants guide.