Plant Identification: Montana’s 1A-2A Species

Noelle Orloff

Montana’s 1A species

Not present or limited presence in MT Eradication if detected Education, prevention key

European Common

Reed (Phragmites

australisssp.

australis)

NEW!

Common reed habitat and distribution

Common Reed Identification

Grows with feet in the water

Usually at least 2m tall

Hairy ligule Inflorescence is

a plumose panicle

Common Reed Identification

Native versus invasive identification difficult

Common Reed Identification

If you suspect you might have the exotic, here is a good resource to help tell the difference. Or call me! http://mnfi.anr.msu.edu/phragmites/phragmites-native-non-native.pdf

Yellow Starthistle

(Centaureasolstitialis)

Similar Species/Critical Diagnostic Features

• Rosettes resemble dandelion and species in mustard family. May need the plant to bolt for positive ID.

• Once bolted, look for winged (flattened) stems, with gray green foliage. Once the plant has bloomed, the yellow flowers with long spiny bracts make it hard to mistake for anything else.

Steve Dewey

Yellow starthistle Tumble mustard

Steve Dewey Matt Lavin

Habitat & DistributionRangelands, pastures, agricultural areas, highways or roads, and in other sunny, disturbed areas

NOTE: Yellow starthistle has been reported in 10 counties in Montana, but all known infestations have been small enough to eradicate. Help to keep it that way by watching vigilantly for this plant and reporting it before it spreads.

Yellow Starthistle(Centaurea solstitialis)

Dyer’s Woad(Isatis

tinctoria)

Dyer’s Woad Identification• Blue green leaves entire, elliptic, prominent white mid-vein • Rosette leaves: petiolate• Stem leaves: sessile and clasping• Corymb of yellow flowers, each with 4 small petals• Grows 1-3’ tall• Pendulous seeds resemble teardrops

Dyer’s Woad Habitat & DistributionGrows in sunny, disturbed areas, thrives in light sandy, gravelly soil.Map below shows all historical records. The Dyer’s woad eradication project has reduced this species to limited populations across Montana

Montana’s 1B species

Limited presence in Montana Eradication or containment Education

Knotweed Complex (Polygonum spp.)

Knotweed Complex: Japanese, Giant, Himalayan & Bohemian Identification

• Herbaceous perennials, 5-19’ tall• Stems hollow• Leaves alternate, membranous sheaths on knobby nodes • Leaf shape generally cordate (heart shaped)• Small greenish-white flowers in sprays, 5 petals (rarely 4)• Spreads rhizomatously, tiny rhizomes fragments can generate into new plants (do not transport soil off-site!). Rarely spreads by seed.

Knotweed habitatCommon near water sources, in low-lying areas, waste places, utility rights-of-way, and around old homesites. Can quickly escape gardens and spread into natural areas.

Dan WilliamsTom Heutte

Dan Williams

Purple Loosestrife (Lythrumsalicaria)

Purple Loosestrife Identification•May be 6-8’ tall •Flowers rose-purple: 5-7 petals•Sepals united/fused: 5-7 lobes•Leaves are opposite, sometime alternate towards tip•Flowers w/out pedicels, meaning inflorescence is a long terminal spike

Elizabeth J. Czarapata dnr.wi.gov

Habitat & DistributionWetlands including freshwater meadows, river and stream banks, pond edges, reservoirs and ditches.

Similar Species/Critical Diagnostic FeaturesPurple LoosestrifeLythrum salicaria

Fireweed (native)Epilobium angustifolium

University of Northern British Columbiaweb.unbc.caBernd Blossey

5-7 petalsSepals fused

4 petals4 distinct linear

sepals

Seeds without any noticeable

appendages

Tufts of hair on seeds for

wind dispersal

Rush Skeletonweed

(Chondrillajuncea)

Rush Skeletonweed Habitat & DistributionCommon along roadsides, in pastures, grain fields and rangelands in well drained, sandy or rocky soils

Rush Skeletonweed Identification• Yellow flowers, all rays• Seeds with dandelion-like plume for wind dispersal• Deeply toothed basal rosette leaves resemble dandelion• Downward bent, coarse hairs on stems

Steve Dewey

Stevens County Weed Board (WA)

Similar Species/Critical Diagnostic FeaturesRush SkeletonweedChondrilla juncea

Skeletonweed (native)Lygodesmia juncea

• 1 to 4’ tall, small linear leaves, basal leaves present

• Up to 18” tall, with small, linear leaves, basal leaves absent

• Ray flowers yellow • Ray flowers pink, purple or white

• Stems with hairs point downwards

• Stems lacking hairs

Scotch Broom (Cytisus scoparius)

Habitat & DistributionCommon in disturbed areas, along roadsides, in pastures, open forests, cultivated fields. Prefers temperate areas, but tolerates very cold conditions.

Scotch Broom (Cytisus scoparius)

Ted Anderson

Scotch Broom Identification• Up to 13’ tall• Yellow pea-shaped flowers• Leaves alternate, egg-shaped

• Upper leaves simple, no petiole• Lower leaves tri-foliate (clover-like)

• Stems angled• Fruit = smooth, flattened pod, ¾-2”long

• Initially green, matures to black

King County Noxious WeedsSteve Dewey Ted Anderson

Montana’s 2A species

Common in isolated areas of Montana Eradication or containment where less

abundant Management prioritized by local weed

districts

(Hang in there, only 9 left!)

Tansy ragwort (Seneciojacobeae)

Tansy ragwort Identification• Grows up to 6’ tall• Biennial, rosette leaves and stem leaves w/blunt toothed lobes, ruffled appearance• Leaves green on top, whitish-green underneath• Composite yellow flowers: ray and disc

King County, WA Noxious Weeds

Michael Shephard

Similar Species/Critical Diagnostic Features

King County, WA Noxious Weeds

Resembles common tansy (Tanacetum vulgare), also with dissected leaves, tall stature, but flowers are discoid, no ray flowers

Many native Senecio species in Montana. Tansy ragwort should have:• No reduction in leaves on the stem (many native Senecio plants

have few stem leaves, mostly basal leaves)• Leaves 2-3 times pinnatifid

Orange hawkweed (Hieracium

aurantiacum)

Orange hawkweed Identification• 20-50 orange flowers in round topped clusters• Ray flowers, square tipped, notched• Densely hairy basal leaves• Milky sap• Stem leaves small to absent (2 or less)

Michael Shephard

Richard Old

Tall hawkweed H. piloselloides

Yellow hawkweed Hieracium floribundum

Meadow hawkweed H. pratense/caespitosum

Meadow Hawkweed Complex Hieracium spp.

Meadow Hawkweed Complex Identification

• Similar to orange hawkweed, except flowers are yellow.

• Flower shape = ray flowers that are square tipped with notches.

• Characteristics such as hairs on bracts and upper & lower leaf surface help identify plants to species.

• Yellow exotic hawkweeds are hard to distinguish from native yellow hawkweeds. Consult a specialist if needed.

• “Hawkweed Identification”, EB 0187, available at: http://msuextension.org/publications/AgandNaturalResources/EB0187.pdf

Tall buttercup (Ranunculus

acris)

Tall Buttercup Identification

• Upright plant, numerous basal leaves, alternate stem leaves• 5 yellow petals, 5 sepals• Leaf blades broadly pentagonal in outline, 3-8 cm. long• Deeply lobed 4-5 times, the lobes incised into pointed segments

Ben Legler

Similar Species/Critical Diagnostic Features

Dave Brink

Tall buttercup Ranunculus acris

Sharpleaf buttercupRanunculs acriformis

Tall buttercup

• Sharpleaf buttercup (Ranunculs acriformis), native, strongly resembles tall buttercup

• Sharpleaf has less than 4 lobes, and lobes are not as deeply indented• Lobes may be wide or narrow, but look for indentation of main lobes nearly to

the base, and at least 4 lobes• Many other native buttercups resemble tall buttercup (yellow, 5-petaled

flowers). Consult a specialist or send a sample to Schutter Diagnostic Lab for a positive ID before initiating control

Perennial pepperweed

(Lepidiumlatifolium)

Perennial pepperweed Identification

• Rhizomatous• Flowers with 4 white petals, in racemes • Silicles ovate, inflated, sparsely hairy • Basal leaves long petioled, serrate margins • Stem leaves smaller, nearly sessile• Stem base semi-woody

Leslie Mehrhoff Steve Dewey

Leslie Mehrhoff

Yellowflagiris (Iris

pseudacorus)

Yellowflag Iris Identification• Only naturalized iris with yellow flowers• Rhizomatous roots have black sap• 4-6’ tall• Reproduces by seed and rhizomes

Similar Species/Critical Diagnostic Features• Only two species of naturalized Iris in Montana: yellowflag iris and

native Rocky Mountain iris (Iris missouriensis).

• Rocky Mountain iris has blue to purple flowers• Not in bloom?

• Leaves of Rocky Mountain iris generally shorter (8 to 16”) • Rocky Mountain iris rhizomes lack black sap

Cheryl Mayer

Rocky Mt Iris

Thayne Tuason

Blueweed (Echiumvulgare)

Blueweed Identification• Basal rosette leaves entire, linear, hairy, 2.5-10” long x ½-3” wide • Stems have stiff hairs with swollen red to black bases• Up to 3’ in height• Five pink or red stamens • Flowers grow in a “helicoid” cyme

Stevens County Noxious Weed Control Board Richard Old

Similar Species/Critical Diagnostic FeaturesBlueweed

Echium vulgareSilverleaf phaceliaPhacelia hastata

Fuzzy basal leaves, prominent mid-rib, no prominent lateral veining

Fuzzy basal leaves, prominent lateral veining

Hairs with swollen red to black bases on stems

Hairs without red to black bases on stems

www.bentler.us

Eurasian watermilfoil

(Myriophyllumspicatum)

Eurasian watermilfoil identification• Aquatic perennial• Compound leaves: >14 paired leaflets• 4 whorled leaves/node• Inconspicuous pink flower spikes rise above water surface• Collapses when removed from water

Alison Fox John HalpopRyan Wersal

Two native milfoils occur in Montana. Can you find the natives below?

So how do you tell the difference?

Whorl-leaf watermilfoilMyriophyllum verticillatum

Native

Eurasian watermilfoilMyriophyllum

spicatumExotic

Shortspike watermilfoilMyriophyllum sibiricum

Native

Frank Koshere, WI DNR

Flowering Rush

(Butomusumbellatus)

Flowering Rush Identification• Pink flowers in an umbel • 3 petals, 3 sepals, nine stamens• Leaves triangular in cross-section• Leaves erect, twist spirally upwards, but limp in depths >10’• Spreads by buoyant rhizomes, fragment easily

Similar Species/Critical Diagnostic Features

• Triangular leaves resemble sedges (Carex spp.), but flowering rush typically much taller.

• Resembles no other native or exotic riparian plants when flowering.

• Unfortunately, does not always flower. Consult a specialist when in doubt.

Jane Larson

Flowering Rush Sedges

Brian Legler Chris Young

For assistance identifying unknown plants, one option is to send samples to the Schutter Diagnostic lab at Montana State University. Please refer to this website for instructions on submitting samples, and to download a form: http://diagnostics.montana.edu/Plant/index2.html

Mailing address: Noelle OrloffSchutter Diagnostic Lab119 Plant BioScience BuildingPO Box 173150Bozeman, MT 59717-3150406-994-6297

Thank you! Questions?