Non native plant id wrkshp Asteraceae Brassicaceae

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NON-NATIVE PLANTS OF ALASKA: Sunflower Family (Asteraceae), Pea Family (Fabaceae), and Mustard Family (Brassicaceae): 

NON-NATIVE PLANTS OF ALASKA: Sunflower Family (Asteraceae), Pea Family (Fabaceae), and Mustard Family (Brassicaceae) Matt Carlson, Irina Lapina, & Helen Cortes-Burns

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Sunflower Family (Asteraceae) Introduction flower head flower head sunflower, artichoke, lettuce hundreds of ornamental species ray flower disk flower

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heads with both disk flowers and ray flowers Senecio jacobea Bellis perennis Achillea spp. Anthemis spp. Leucanthemum Tripleurospermum inodorum Heads with only disk flowers Cirsium arvense Cirsium vulgare Cotula coronopifolia Matricaria discoidea Centaurea biebersteinii Tanacetum vulgare Heads with only ray flowers Taraxacum officinalis & T. officinalis ssp. ceratophorum Crepis tectorum Hieracium aurantiacum Hieracium caespitosum H. pilosella H. umbellatum Hypochaeris radicata Leontodon autumnalis Sonchus arvensis Tragopogon dubious Sunflower Family (Asteraceae) Introduction

Common dandelion Taraxacum officinalis ssp. officinale: 

Common dandelion Taraxacum officinalis ssp. officinale Yellowflowered Asteraceae Heads with only ray flowers perennial flowering stalk leafless and hollow all leaves basal and lobed Arctic-Alpine Interior Boreal South Coastal ecogeographic regions roadsides, railroads, waste places, lawns, cultivated fields meadows in Glacier Bay National Park and Preserve Nenana and Stikine Rivers bars burned areas in Kenai Peninsular Horned dandelion Taraxacum officinalis ssp. ceratophorum Sunflower Family (Asteraceae) Hultén 1968, Royer & Dickinson 1999, Whitson et al. 2000

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Yellowflowered Asteraceae Heads with only ray flowers Narrowleaved hawkweed Hieracium umbellatum perennial, 1 ½ to 4 feet tall from a short woody rhizome flower head up to 1 inch across no basal rosette of leaves involucral bracts multiple lengths, dark green to black without stolons roadsides, forest edges and openings in Interior Boreal and South Coastal ecogeographic regions Narrowleaved hawksbeard (Annual hawksbeard) Crepis tectorum Sunflower Family (Asteraceae) annual or winter annual, erect, 1 to 3 feet tall flower head ½ to 5/8 inches across involucral bracts in two rows winter annual with basal rosette of leaves roadsides, disturbed areas Arctic-Alpine Interior Boreal South Coastal ecogeographic regions Gubanov et al. 2004, Hultén 1968, Royer & Dickinson 1999, Whitson et al. 2000

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Yellowflowered Asteraceae Heads with only ray flowers Meadow hawkweed Hieracium caespitosum perennial, up to 3 feet tall short, stout rhizome and long, leafy stolons basal rosette of leaves stem and leaves with numerous hairs heads 7 or more on branched stems milky juice roadsides, disturbed areas, and waste places South Coastal ecogeographic regions (collected in Juneau and Valdez) perennial, about 1 feet tall mat-forming stolons basal rosette of leaves stem and leaves with sticky hairs heads solitary on unbranched stems outer ray flowers often with a reddish lines on the outer surface milky juice roadsides, lawns, and waste places in lowland, and montane zones Collected in Kenai Peninsula Sunflower Family (Asteraceae) Douglas et al. 1998 Mouseear hawkweed Hieracium pilosella

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Yellowflowered Asteraceae Heads with only ray flowers Hieracium triste Alaska native hawkweed species all native hawkweed species lack stolons basal leaves are present by flowering time no or very few small stem leaves involucral bracts with dark black or grayish-black hairs forest, meadows, streambanks, and snowbeds in the subalpine to alpine zones Exotic and native hawkweed species hybridize freely Hieracium gracile Sunflower Family (Asteraceae) Hultén 1968

Hairy cats-ear Hypochaeris radicata: 

Yellowflowered Asteraceae Heads with only ray flowers Hairy cats-ear Hypochaeris radicata perennial, ½ to 2 feet tall rosette of basal leaves stem branched with scalelike bracts stem leaves lacking flower head is 1 to 1½ inches across milky juice receptacle chaffy (bracted) achenes with long, slender beak roadsides, lawns, pastures, and waste places in lowland zone South Coastal ecogeographic regions Fall dandelion Leontodon autumnalis perennial rosette of basal deeply toothed leaves stem leaves lacking scalelike bracts on the stem milky juice receptacle naked achenes beackless roadsides, pastures, and disturbed sites in the lowland and montane zones Interior Boreal South Coastal ecogeographic regions Sunflower Family (Asteraceae) Douglas et al. 1998, Pojar & Mackinnon 1994

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Yellowflowered Asteraceae Heads with only ray flowers Perennial sow thistle Sonchus arvensis looks like giant dandelion perennial, succulent, 2 to 4 feet tall extensive rhizomes leaves have a clasping base upper leaves are much smaller flower heads are big 1 to 2 inch across yellow gland-tipped hairs on the stems below flower heads milky juice roadsides, gardens, cultivated fields, and waste areas It may occur on disturbed sites of prairies, woods, meadows, lawns, streams, and lake shores Interior Boreal South Coastal ecogeographic regions S. arvensis ssp. uliginosus commonly up to 6 feet tall has a waxy bloom on the stem does not have yellow hairs on the floral bracts or stem floral bracts are green with white margins Sunflower Family (Asteraceae) Douglas et al. 1998, Gubanov et al. 2004, Hultén 1968, Royer & Dickinson 1999, Whitson et al. 2000

Annual sowthistle (Common sowthistle) Sonchus oleraceus: 

Yellowflowered Asteraceae Heads with only ray flowers Annual sowthistle (Common sowthistle) Sonchus oleraceus annual, 1 to 4 feet tall leaves are lobed upper leaves with sharply pointed lobes, clasping the stem flower heads relatively small less than 1 inch across roadsides, cultivated fields, gardens Interior Boreal South Coastal ecogeographic regions Spiny sowthistle (also called annual sowthistle) Sonchus asper annual, 1 to 5 feet tall leaves entire with sharp, stiff prickles large rounded lobes at the stem flower heads relatively small less than 1 inch across roadsides, waste areas, gardens, and cultivated fields Interior Boreal South Coastal ecogeographic regions Douglas et al. 1998, Gubanov et al. 2004, Hultén 1968, Royer & Dickinson 1999, Whitson et al. 2000 Sunflower Family (Asteraceae)

Goat’s beard (Yellow salsify) Tragopogon dubius: 

Yellowflowered Asteraceae Heads with only ray flowers biennial or perennial, 1-3 feet tall leaves grass-like, 12” long floral bracts are longer than the flowers (up to 1½ inch long) stem is hollow and swollen below the flower head fruiting head is globe-shaped, 2½ to 4 inches arcoss milky juice roadsides, waste areas steep slopes and slides are susceptible to invasion has been collected along the Turnagain Arm Sunflower Family (Asteraceae) Goat’s beard (Yellow salsify) Tragopogon dubius Douglas et al. 1998, Royer & Dickinson 1999

Native yellowflowered Asteraceae: 

Native yellowflowered Asteraceae Several native yellowflowered Asteraceae species with narrow grass-like leaves (Microseris borealis, Agoseris glauca e.g.) can be found in wet meadows or wet rocky slopes along the coast. They usually have solitary unbranched and leaveless flower stem MICROSERIS BOREALIS Hultén 1968, Pojar & Mackinnon 1994 Yellowflowered Asteraceae Heads with only ray flowers Sunflower Family (Asteraceae)

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orangeflowered Asteraceae Heads with only ray flowers Orange hawkweed Hieracium aurantiacum perennial flowers orange basal leaves form rosette rhizomes and above-ground stolons forming dens mats milky juice No other composite species in Alaska has dark orange to red flower heads roadsides, disturbed areas and waste places it invades forbs-fern meadows in Kodiak Hultén 1968, Royer & Dickinson 1999 Sunflower Family (Asteraceae)

Yellowflowered Asteraceae Heads with only ray flowers: 

Yellowflowered Asteraceae Heads with only ray flowers plant with leafless stem plant with leafy stem flowering stalk hollow with no scalelike bracts no horns on the bracts under the flower heads flowering stalk with scalelike bracts horns on the bracts under the flower heads Taraxacum officinale ssp. officinale Taraxacum officinale ssp. ceratophorum Hypochaeris radicata Leontodon autumnalis Hieracium pillosella Hieracium caespitosa winter annual Crepis tectorum annual Crepis tectorum Hieracium umbellatum Sonchus oleraceus Sonchus asper Sonchus arvensis Sonchus arvensis ssp. uliginosus Tragopogon dubius Hieracium triste achens with long beak achenes without beak single flower head heads 7 or more on stalk involucral bracts in two rows involucral bracts multiple lengths leaves grasslike parallel-veined Leaves soft lobed with sharp-pointed lobed at stem leaves stiff with spiny margins rounded lobes at the stem gland-tipped hairs on flower stalk and bracts lack of gland-tipped hairs on flower stalk and bracts plant has leafy stolons stem leaves broad with prickly margins involucre onion shape at fruit stem leaves lanceolate to narrowly oblong usually less than 1/2” involucla cilindrical at fruit plant without stolons annual (biennial) with short root heads small (<1”) plant with rosette of basal leaves at flowering time plant with no rosette of basal leaves at flowering time involucral bracts in two rows involucral bracts multiple lengths Hieracium gracile stem leaves broad, wide (not grasslike) perennial with deep root and rhizomes heads large (up to 2”) Key to yellowflowered aster of disturbed habitats

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annual small, less than 1 feet tall cone-shaped flower heads plant gives off a scent when crushed leaves are divided several times into narrow segments on compacted soil of roadsides, farmyards, waste areas throughout Alaska yellowflowered Asteraceae Heads with only disk flowers Pineappleweed Matricaria discoidea Hultén 1968, Pojar & Mackinnon 1994, Royer & Dickinson 1999 Common groundsel Senecio vulgaris annual or biennial hollow stem, 4 to 12 inches tall leaves fleshy, wavy-margined, deeply lobed cylindrical flower heads roadsides, gardens, cultivated crops throughout Alaska Sunflower Family (Asteraceae)

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yellowflowered Asteraceae Heads with only disk flowers Common brassbuttons Cotula coronopifolia perennial 2 to 12” tall stems trailing and rooting at the nodes leaves narrowly oblong, entire or with few teeth head solitary at ends of branches beaches, tidal mudflats and marshes in southeast Alaska Hultén 1968, Pojar & Mackinnon 1994, Royer & Dickinson 1999 Common tancy Tanacetum vulgare perennial, grow up to 4 feet tall stem woody, purplish red leaves are twice-divided into narrow, toothed segments leaves have strong odor when crushed numerous button-like flower heads roadsides, can be found along ditches and streams it invades beach meadows in Haines, SE Sunflower Family (Asteraceae)

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Fernleaf yarrow Achillea filipendulina Tansy ragwort Senecio jacobaea biennial or short-lived perennial 4 to 6 feet tall lower leaves soon deciduous leaves deeply pinnately dissected leave segments are wider than long numerous flowerheads with light brown centers ray flowers up to ½” long roadsides, disturbed places in Anchorage, and Southeast Alaska yellowflowered Asteraceae Heads with both disk flowers and ray flowers Bossard et al. 2000, Pojar & Mackinnon 1994 ray flowers short, 2-4mm long roadsides in Anchorage Sunflower Family (Asteraceae)

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Heads with white ray flowers and yellow disk flowers Oxeye daisy Leucanthemum vulgare (Chrysanthemum leucanthemum) Arctic daisy Dendranthema arcticum (Leucanthemum arcticum, Chrysanthemum arcticum) perennial, 1 to 3 feet tall flowerheads with white ray flowers and yellow disc florets leaves spoon-shaped, with rounded teeth and lobes leaves usually withered by flowering time roadsides, meadows, clearcuts, disturbed places Interior Boreal and South Coastal ecogeographic regions Bossard et al. 2000, Hultén 1968, Royer & Dickinson 1999, Pojar & Mackinnon 1994, Welsh 1974, Whiston et al. 2000 native perennial, maritime species of rocky or gravelly beaches and salt marshes often less than 1 feet tall leaves wedge-shaped with 3-7 blunt lobes leaves usually present at flowering time along the seashore throughout coastal Alaska Sunflower Family (Asteraceae)

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Scentless chamomile Tripleurospermum perforata Heads with white ray flowers and yellow disk flowers Stinking mayweed Anthemis cotula receptacles naked involucral bracts with dark-brown, broad, scarious margin annual or biennial flowerheads with white ray flowers and yellow disc flowers leaves divided into narrow segments roadsides, cultivated crops, waste places in Arctic Alpine, Interior Boreal and South Coastal ecogeographic regions False mayweed Tripleurospermum maritima receptacles papery or bristly on the middle plant ill-scented Sunflower Family (Asteraceae) receptacles naked leaves are odorless when crushed involucral bracts with light-brown, narrow, scarious margin

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Yarrow Achillea millefolium complex Common yarrow Achillea millefolium var. millefolium Yarrow Achillea millefolium var. occidentalis Yarrow Achillea millefolium var. borealis Heads with both ray flowers and disk flowers probably introduced involucral bracts with light-brown to yellowish margin perennial, aromatic plant, 1 to 2 feet tall, rarely branched with woolly hairs leaves divided 2-3 times into narrow segments flowerheads small (3/8” across) with 5 white to pink ray flowers and cream colored disc flowers numerous flowerheads in round, flat-topped clusters roadsides, waste places, meadows, open forests, rocky slopes, gravel bars throughout Alaska native involuclal bracts with dark-brown margin native involucral bracts with light-brown to yellowish margin leaves narrow Hitchcock et al. 1955, Hultén 1968, USDA Plants Database 2003, ITIS 2003 New FNA treatment will not recognize A. borealis. Achillea millefolium = a complex of native and introduced genotypes that are impossible to distinguish morphologically or cytologically (D. Trock) Sunflower Family (Asteraceae)

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Sneezewort (Sneezeweed) Achillea ptarmica Yarrow Achillea sibirica Heads with both ray flowers and disk flowers introduced, escaped from cultivation perennial leaves lanceolate, toothed ray flowers white, disk flowers greenish-white ray flowers 1/4 “ long roadsides, forest edges, Interior Boreal and South Coastal ecogeographic regions` native, cultivated perennial leaves lanceolate, lobed roadsides, meadows and foods, Interior Boreal ecogeographic region Sunflower Family (Asteraceae) Hultén 1968, USDA Plants Database 2003, ITIS 2003

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purplish pink flowered Asteraceae Heads with only disk flowers Canada thistle Cirsium arvense Bull thistle Cirsium vulgare perennial, 1 to 4 feet tall forms colonies through extensive creeping rhizome prickly stems and leaves without spiny wings leaves are glabrous above and glabrous or hairy below purplish pink flowers flowerheads up to 3/4” across bracts under the flowerhead are spineless roadsides, forest edges, forest openings, Interior Boreal and South Coastal ecogeographic regions` biennial, 2 to 5 feet tall deep, fleshy taproot spiny-winged stems leaves are prickly hairy above and cottony below dark purple flowers large head (up to 1 1/2”) bracts under the flowerhead are spine-tipped roadsides, disturbed sites, Interior Boreal and South Coastal ecogeographic regions` Royer & Dickinson 1999, Whitson et al. 2000 Sunflower Family (Asteraceae)

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Spotten knapweed Centaurea biebersteinii (C. maculosa) biennial or short-lived perennial stem and leaves have sandpapery texture lower leaves irregularly lobed, upper leaves entire flowers purple bracts under the flowerhead black-tipped, not spiny purplish pink flowered Asteraceae Heads with only disk flowers No native species of knapweed are present in Alaska Native thistles are restricted to western Aleutians, southern tip of SE AK, and potentially Haines & Skagway area Sunflower Family (Asteraceae) Royer & Dickinson 1999, Whitson et al. 2000

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herbs, shrubs, vines, trees roots with nitrogen-fixing bacterial nodules leaves alternate compound flower composed of 5 sepals, 5 petals, 10 stamens, one style fruit a legume peanuts, beans, peas, lentils, alfalfa Legume Family (Fabaceae) Introduction Standard – upper petal of the flower Wings – two side petals Keel – lower 2 petals, fused to form a keel

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Legume Family (Fabaceae) Introduction compound leaves trifoliate palmate pinnate with tendrils pinnate

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Legume Family (Fabaceae) White sweetclover Melilotus alba Yellow sweetclover Melilotus officinalis biennial, 2 to 5 feet tal leaves compound with 3 leaflets flowers white, fragrant roadsides, waste areas sand dunes and gravel bars along the Stikine River (Tongass National Forest), Nenena and Matanushka river in south central Alaska annual or biennial, 2 to 5 feet tall leaves compound with 3 leaflets flowers yellow roadsides, waste places much less common Royer & Dickinson 1999, Whitson et al. 2000

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White clover Trifolium repens Red cliover Trifolium pratense Alsike clover Trifolium hybridum perennial creeping stems, rooting at the nodes leaves with 3 leaflets each usually ½ to 1 ½ “ long leaflets often have V marks flowers white to pinkish white in long-stalked heads up to 1” in diameter roadsides, lawns, waste areas in Arctic-Alpine, Interior Boreal, and South Coastal ecogeographic regions reddish pink flowers in a globe-shaped clusters leaves immediately below head leaflets each 1-2” long leaflets often have V marks roadsides, lawns, waste areas in Interior Boreal, and South Coastal ecogeographic regions Legume Family (Fabaceae) upright stems not rooting at the nodes pinker flower roadsides, lawns, waste areas in Arctic-Alpine, Interior Boreal, and South Coastal ecogeographic regions Several more clover species have been recorded in Alaska. All clovers in Alaska are introduced Hultén 1968, Royer & Dickinson 1999

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Black medic Medicago lupulina Yellow alfalfa Medicago sativa ssp. falcata Alfalfa Medicago sativa annual to perennial, 3 feet tall erect or ascending stem leaves compound with 3 leaflets flowers up to 1/2” long, blue to purple, in globe-shaped or ovate clusters pods spirally coiled loosely 2-3 times pods 10-20 seeded roadsides, disturbed sites, near cultivated fields in Interior Boreal and South Coastal ecogeographic regions annual, 1 feet tall stem hairy, low trailing leaves compound with 3 hairy leaflets flowers yellow, small 2/8” long clusters of flowers globe-shaped about 5/8” across pods kidney-shaped pods 1-seeded, black when ripe roadsides, lawns, cultivated crops Arctic Alpine, Interior Boreal, and South Coastal ecogeographic regions Legume Family (Fabaceae) perennial in cultivation escaped behaves as an annual up to 3 feet tall stem decumbent or erect leaves compound with 3 leaflets flowers yellow, 3/8-1/2” long pods falcate or nearly straight pods 2-5 seeded roadsides, waste places, near cultivated fields in Fairbanks area and Matanuska Susitna Valley Hultén 1968, Royer & Dickinson 1999, Pojar & Mackinnon 1994, Welsh 1974, Whitson et al. 2000

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Bird vetch Vicia cracca Winter vetch (Hairy vetch) Vicia villosa annual or biennial very hairy plant stem not winged leaves with 7-9 pairs of leaflets flowers are two-colored (purple and white, or red and white) disturbed soil, one location in Anchorage perennial with climbing or trailing stems to 6 feet tall stem not winged leaves with 8-10 pairs of leaflets and branched tendrils flowers bluish violet in dense, one-sided clusters of 20-50 flowers roadsides, forest edges and openings, thickets in Interior Boreal and South Coastal ecogeographic regions Legume Family (Fabaceae) Hultén 1968, Pojar & Mackinnon 1994

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stem winged 2-3 pairs of leaflets wet meadows Interior Boreal and South Coastal ecogeographic regions Native Lathyrus, Hedysarum, Astragalus, and Vicia species leaflets broadly ovate without tendrils sandy shores along the coast stem erect, not climbing or trailing leaves odd pinnate inflorescence long leaflets broad lanceolate or oblong roadsides, Alaska Pipeline right-off-way rocky slopes, river bars, spruce forest, gravel bars Interior Boreal and South Coastal ecogeographic regions MARCH PEA (LATHYRUS PALUSTRIS) BEACH PEA (LATHYRUS JAPONICUS) HEDYSARUM ALPINUM Legume Family (Fabaceae) Hultén 1968, Pojar & Mackinnon 1994

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perennial up to 5 feet tall from woody rhizome, stem erect, hollow at least at the base leaves palmately compound, 10-18 leaflets basal leaves 6-8” in diameter, long-stalked lowers blue to violet in dense long clusters to 16” tall hairy pods to 2” long roadsides, open woods, often near habitations, cultivated, extremely abundant on burned areas from vicinity of Fairbanks to southern Alaska Legume Family (Fabaceae) Arctic lupine (Lupinus arcticus), and Nootka lupine (Lupinus nootkatensis) leaves smaller leaflets fewer (5-8) dry and damp slopes, gravel bars, roadsides, Hultén 1968, Pojar & Mackinnon 1994

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Scotch broom Cytisus scoparius Siberian pea-shrub Caragana arborescens shrub up to 10 feet tall leaves with 8-12 leaflets, oblong to eliptic spiny stipules flowers yellow, borne singly ornamental, planted in Anchorage and Fairbanks (“should be more widely planted” Welsh 1974) shrub, 6-10 feet tall branches green and strongly 5-angled with 5 ridges unarmed leaves with 3 leaflets, pressed close to the branches flowers bright-yellow, single roadsides, meadows, open woods, forest clearcuts South Coastal (Ketchikan, Prince of Wales Island) Legume Family (Fabaceae) Bossard et al. 2000, Pojar & Mackinnon 1994, Welsh 1974

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annual or perennial herbs alternate simple leaves, lobed often with basal rosette plant often with hairs flowers in racemes flowers with 4 petals and 4 sepals arranged in cross fruit is pod-like, open from the base toward the apex silique (longer than broad) or silicle (wider than long) with membranous partition shepherd’s purse, mustards, flixweeds, peppergrass Mustard Family (Brassicaceae) introduction silicles siliques

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Mustard Family (Brassicaceae) introduction star-shaped hairs forked hairs simple glandular hairs plants often with hairs simple hairs

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Shepherd’s purse Capsella bursa-pastoris Mustard Family (Brassicaceae) annual or winter annual flowers white pods triangular, 2/8-3/8” long leaves from slightly to deeply lobed rosette of leaves stem leaves are stalkless, clasping roadsides, cultivated fields, waste areas Interior Boreal and South Coastal ecogeographic regions Hultén 1968, Royer & Dickinson 1999 Lyrate rockcress Arabis lyrata fruit is up to 1 ½” long sandy and rocky slopes, open areas Interior Boreal and South Coastal ecogeographic regions, common along the coast

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annual or winter annual flowers are small, inconspicuous, less than 1/8” wide flowers densely arranged along the stem leaves basal, toothed or deeply lobed fruit heart-shaped to round, about 1/8” long, contains 2 seeds roadsides, cultivated fields, waste areas Interior Boreal and South Coastal ecogeographic regions Hultén 1968, Royer & Dickinson 1999, Pojar & Mackinnon 1994 Mustard Family (Brassicaceae)

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Dame’s rocket Hesperis matronalis Mustard Family (Brassicaceae) perennial, ornamental flowers purple about 1” across, fragrant leaves alternate and hairy, fruit ¾ to 6” long roadsides, ditches, gardens Interior Boreal and South Coastal ecogeographic regions one only mustard species in Alaska with such a big showy purple or pink flowers

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Garlic Mustard Alliaria petiolata Mustard Family (Brassicaceae) biennial up to 3 feet tall plant has a strong garlic odor when crushed flowers white stem unbranched basal leaves kidney-shaped, stem leaves are heart-shaped 2-4” wide roadsides, abandoned field, open forest, clearcuts Juneau There are a number of white flowered mustards in Alaska, but none have large, well-developed and toothed stem leaves, or are garlic-scented.

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Erysimum cheiranthoides Mustard Family (Brassicaceae) annual or winter annual up to 3 feet tall, occasionally branched flowers yellow leaves not lobed plant covered with short hairs that have 2 to 3 branches fruit 1 ¼” long, 4-angled pods are held erect and parallel to the stem roadsides, forest edges, shrubs throughout Alaska Hultén 1968, Royer & Dickinson 1999, Pojar & Mackinnon 1994

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Field mustard Brassica rapa Mustard Family (Brassicaceae) winter annual or biennial growing 1-4 feet tall stem and foliage usually smooth lower leaves to 1 foot long, with large terminal lobe and smaller lateral lobes upper leaves are small and non-lobed, clasping flowers yellow pods lack hairs, 1½-2½” long on long pedicels pod has a conspicuous beak, 2/4-3/4” long, round in cross section roadsides, cultivated fields, waste areas in Interior Boreal and South Coastal ecogeographic regions Whitson et al. 2000 Charlock Sinapis arvensis leaves obovate, divided or entire flowers yellow fruit with scarcely compressed beak

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Tumbling mustard Sisymbrium altissimum Mustard Family (Brassicaceae) annual, winter annual, or biennial up to 4 feet tall pale-green plant with numerous branches flowers pale yellow leaves 12” long, divided into thread-like segments pods 2-4” long roadsides, waste ground, back yards Interior Boreal and South Coastal ecogeographic regions Hultén 1968, Royer & Dickinson 1999, Pojar & Mackinnon 1994

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Descurainia sophia Mustard Family (Brassicaceae) annual, winter annual, or biennial up to 3 feet tall with numerous branches plant greyish green hairs grey, star-shaped flowers yellow leaves divided into narrow segments roadsides, crops Arctic Alpine and Interior Boreal ecogeographic regions Descurainia sophioides very similar to D. shophia hairs simple, glandular gravel bars, disturbed soil, roadsides throughout the Arctic Alpine and Interior Boreal ecogeographic regions

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fruit silicle (3-4 times as long as broad) Mustard Family (Brassicaceae) Key to Mustards of disturbed habitats, part 1 (consult Hultén (1968) or Welsh (1974) for more information about mustards in Alaska) flowers white or small and inconpicuous plant without hairs flowers yellow all hairs simple plant with hairs star-shaped hairs, sometimes mixed with simple all hairs simple star-shaped hairs, sometimes mixed with simple Thlaspi arvense Lepidium spp. Capsella bursa-pastoris Rorippa Neslia paniculata Adapted from Hultén (1968)

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fruit silique (more than 4 times as long as broad) Mustard Family (Brassicaceae) flowers white, pink, or purplish plant without hairs flowers yellow all hairs simple plant with hairs hairs forked, branched, or star-shaped, sometimes mixed with simple hairs all hairs simple Arabis (6 native spp.) Raphanus sativus Descurainia sophioides Sinapis arvensis Sisymbrium altissimum basal leaves simple, entire, toothed basal leaves lyrate or pinnate stem leaves pinnate stem leaves entire Arabis Hesperis matronalis Sisymbrium officinale Brassica (3 introduced spp.) Erysimum cherianthoides or E. canescens Rorippa (2 yellowflowered spp.) flowers small (2 -9mm across) flowers large (1” across) lower leaves divided 2 or 3 times into narrow segments lower leaves, as well as other, neither 2 or 3 divided siliques with stout beak, seeds globular siliques beakless, seeds oblong beak of silique flat, sepals spreading horisontally beak of silique round in cross section, sepals not spreading siliques not awl-shaped, not appressed to rachis, much <2½” long siliques awl-shaped, appressed to rachis, leaves with large apical lobe siliques not awl-shaped, not appressed to rachis, siliques 2 ½-4” long, leaves with long linear segments hairs forked, branched, or star-shaped, sometimes mixed with simple hairs hairs forked, closely appressed, straight, 2-3 pronged, attached near the middle hairs star-shaped, branched Descurainia Adapted from Hultén (1968) Key to Mustards of disturbed habitats, part 2 (consult Hultén (1968) or Welsh (1974) for more information about mustards in Alaska)