Download Invasive Species Field Aid - Deer Grove East | Friends of Deer

Invasive Species Field Aid
Invasive Shrubs
Rhamnus cathartica-European Buckthorn
Forms wall-like thickets. When cutting, the stumps MUST BE brushed with herbicide as soon as possible to prevent re-sprouts.
Buckthorn has a unique leaf veination where the side veins curve out from the bottom of the midvein. If you hold the leaf horizontal, the veins form the shape of a closed eye. If you scrape off the bark on a buckthorn shrub, either on the trunk or a branch it has a bright orange color. The buckthorn fruit ripens in late summer and turns a very dark purple.
Single and multiple buckthorn seedlings. Lonicera sp. - Bush honeysuckles (Japanese, Tartarian, Amur)
Sometimes can be vines. When cutting, the stumps MUST BE brushed with herbicide as soon as possible to prevent re-sprouts.
Flowers are mostly white. Honeysuckle form large tangled patches. Most honeysuckles have tan bark with striped texture. The older stems are hollow. Honeysuckles produce red fruit.
Similar species: There are some native honeysuckles in the region. Because they are all very conservative species, they will most likely not be
found in invasive thickets of exotic species. The most common native honeysuckle (yellow honeysuckle) has yellow flowers.
Lonicera canadensis‐ American Fly Honeysuckle (native) End leaves are round, flowers yellow. Stem is not hollow‐pith is solid and white.
Flowers are bell‐like. Shrubs less dense. Rosa multiflora (Multiflora rose)
Similar to all rose bushes but forms thick, tangled patches. When cutting, the stumps MUST BE brushed with herbicide as soon as possible to
prevent re-sprouts.
Has white flowers. Has seven‐leaf pattern on branches. Stipule of multiflora rose is hairy, while it is usually smooth on native roses. Produces red rose hips. Berberis thunbergii (Japanese Barberry)
Small leaves. Berries turn from orange to red. Barberry seedling Has thorns. Cornus racemosa (Gray Dogwood)
A native shrub that occupies a variety of habitats,including woodlands and edges of prairie. Due to fire suppression, large thickets have formed
in some prairie remnents and therefore need thinning to improve biodiversity.
Mature shrub with white flowers. Leaves opposite and twigs gray. White fruits. Similar species: There are several native dogwoods that are conservative species found in various wooded habitats. Gray dogwood has gray
twigs, while the other species usually have yellowish, greenish or reddish twigs depending on the species.
Cornus rugosa Round‐leaved Dogwood Cornus alternifolia Pagoda Dogwood Cornus stolonifera Red‐Osier Dogwood Invasive Herbaceous
Alliaria petiolata (Garlic Mustard)-Biennial that invades the understories of woodlands. Had a distinctive garlic smell. MUST BE pulled before
going to seed.
Rosette‐Year 1 Flowering‐Year 2
Group of year 2 plants. Similar species-rosettes can be confused with leaves of native violets. Flowers look slightly like native white avens.
Viola papilionacea Common Blue Violet Viola pensylvanica Smooth Yellow Violet Geum canadense White Avens Phalaris arundinacea (Reed Canary Grass)-Invades wet areas.
Seedling. Notice three‐blade pattern Young plant. Notice alternate blades and blades at the top. Mature stem with blades. Flowering spikelets Seeding spikelets Notice distinctive white ligule. Similar species- Can be confused with native Calamagrostis canadensis (Blue-joint grass)
Note “more open” flower heads Note blue stem joint and no white ligule
Clump of Calamagrostis
Lythrum salicaria (Purple Loosestrife) Invades wet areas. Has extensive roots
Flowering Leaves attach to stem without leaf stalk
Sprouting from fall dieback stems.
Similar species-native Lythrum alatum ( winged loosestrife) looks similar but has smaller, winged, alternate leaves. Purple loosestrife flowers
are similar in color and slightly in shape to native Liatris spicata (blazing star)
Lythrum alatum Liatris spicata Phragmites australis (Phragmites)
Invades wet areas.
Mature stems and blades. Sprouting from horizontal stem.
Feathery seed head.
Large invading patch Cirsium vulgare-(Bull Thistle) Biennial that invades grassy areas and wood edges.
Rosette‐year 1 Mature plant with thorns‐year 2 Flowering Seeding Cirsium arvense (Canada Thistle)- Biennial that invades grassy areas and wood edges.
Rosette‐year 1 Mature plant with flowers and thorns‐year 2
Seeding
Similar species-Native thistles are rare. Cirsium hilli has a single bloom. The underside of the leaves of Cirsium discolor are white.
Cirsium discolor‐Pasture Thistle Cirsium hillii –Prairie Thistle Euphorbia esula (Leafy Spurge)
Mature plant with flowers‐notice flat flowers. Mature plant with flowers Mature plant with flowers Similar species-Flat top flowers slightly resemble some native goldernrods, but spurge flowers are larger and rounder.
Solidago gramnifolia Solidago ohiensis Solidago rigida Melilotus alba and Melilotus officianalis-( White and Yellow Sweet Clover)
Invades grassy areas.
White sweet clover flower and leaves. Yellow sweet clover flower and leaves. Yellow and white sweet clover invading Similar species-has typical legume three-leafed pattern but prairie clover flowers are round, not spiked.
Lespedeza capitata‐Round headed Bush Clover Lespedeza hirta‐Hairy Bush Clover Dipsacus sp. (Cut-leaf and common teasel)
Biennial that invades grassy areas. VERY thorny.
Rosette‐year 1 Mature plant‐year 2 Flowering Seeding Dry seed head Ranunculus ficaria (Lesser Celandine)
Invades wet woodlands,woodlands with sandy soil and floodplains. Very aggressive and displaces spring ephemerals.
Flowers usually have 8‐12 petals Kidney‐shaped leaves
Invasion
Bulbets at bottom of stem.
Similar species- It is often mistaken for Caltha palustris (Marsh marigold) because flowers and leaves look similar. Also, both marsh marigold
and lesser celandine grow in wet habitats
Has sepals, not petals: usually 5‐9. Leaves are more heart shaped than kidney shaped. Grows in single clumps, not like a carpet as lesser celandine does. Has no bulbets. Marsh marigold can be up to 2 ft. tall, while lesser celandine is shorter. Coronilla varia (Crown Vetch)
Brought from Europe as an erosion control plant. Forms large monocultures.
Group of crown vetch plants. Notice typical legume leaf pattern.
Clover‐like purple flower
Similar species-legumes have similar leaves so crown vetch can be confused with various native legumes. However, the pattern of monoculture
growth and the degraded habitat crown vetch is found in serves as a strong indication that it is not a native legume, which are usually
conservative species.
Astragalus neglectus Cooper’s Milk Vetch
Cassia nicitans Wild Sensitive Plant
Lathyrus ochroleucus Pale Vetchling Lathyrus palustris Marsh Vetchling Lathyrus venosus Veiny Pea Invasive Vines
Celastrus orbiculatus (Oriental Bittersweet)- Invades by climbing over trees in woody areas
Leaves and distinctive yellow fruit. Invading. Invading. Similar species-Native bittersweet (Celastrus scandens) leaves are much longer than wide and flowers are at the end of branches while
invasive bittersweet has leaves only slightly longer than wide and flowers are in the axils.
Celastrus scandens
Invasive Trees-When removing native invasives take great care to identify correct habitat in determining invasiveness. Proper identification of species is imperative.
Ailanthus altissima (Tree of Heaven)-invades all types of areas. Can grow in concrete cracks. Has an unpleasant odor.
Leaves and seeds Notch at base of leaf
Bark
Similar species-resembles native honey locust (Gleditsia triacanthos) but honeysuckle has thorns and rounder leaf tips
Gleditsia triacanthos-Honey Locust Populus alba (White Poplar)-invades grassy areas and wetter wooded areas. Forms extensive clones
Distinctive spotted, white bark. Leaves with silvery underside Similar species-resembles native cottonwood (Populus deltoides) but cottonwood does not have white bark, but grayish and very furrowed.
Populus deltoides- Cottonwood
Robinia pseudoacacia (Black Locust)-Invades woodlands. Forms extensive clones.
Leaves and flowers Mature bark
Similar species-slightly resembles native Kentucky coffee tree ( Gymnocladus diocia)
Gymnocladus diocia-Kentucky Coffee
Sapling
Fraxinus pennsylvanica-Green Ash -Native floodplain and upland forest understory species. Due to lack of fire, saplings can be invasive in
oak woodlands/prairies
Leaf Opposite branching Smooth gray bark in sapling Similar species-Sapling bark can resemble other saplings such as oaks, maples and elms.
Acer negundo ( Box elder)- Native floodplain and upland forest understory species. Due to lack of fire, saplings can be invasive in oak
woodlands/prairies
Leaf Sapling Similar species-Leaves resemble poison ivy. Bark can resemble other species such as oaks, maples and elms.
Mature bark Prunus serotina (Black Cherry)- Native floodplain and upland forest understory species. Due to lack of fire, saplings can be invasive in oak
woodlands/prairies. NOTE-Black cherry has a high amount of cyanide in it. Don’t eat it!
Leaves and fruit Glands on leaf base Bark of sapling Mature “potato chip” bark Similar species-Sapling bark can resemble other saplings such as oaks, maples and elms. Mature bark is distinctive.
Acer saccharum (Sugar maple) -)- Native floodplain and upland forest species. Due to lack of fire, saplings can be invasive in oak
woodlands/prairies
Leaf Similar species-Bark can resemble other species such as oaks, maples and elms.
Young tree bark
Acer saccharinum (Silver maple) -Native floodplain and upland forest species. Due to lack of fire, saplings can be invasive in oak
woodlands/prairies
Leaves‐notice silver underside Saplings
Similar species-Bark can resemble other species such as oaks, maples and elms.
Tilia americana (Basswood)- Native floodplain and upland forest species. Due to lack of fire, saplings can be invasive in oak
woodlands/prairies
Leaves‐notice uneven leaf base Bark of sapling
Mature bark
Similar species-Bark can resemble other species such as oaks, maples and elms.
Quercus alba‐White Oak
Quercus macrocarpa‐Bur Oak Quercus rubra‐Red Oak