United States Department of Agriculture INVASIVE PLANTS of the Plumas National Forest

A Comparison Guide to Non-native Invasive Plants and Common Look-alikes

Forest Plumas Publication June Service National Forest R5-TP-036 2014 Invasive Plants Non-native invasive plants are aggressive plants that have been introduced into an environment outside of their of the Plumas National Forest native range. Sometimes referred to as alien species, these invasive weeds have been separated from the natural A Comparison Guide to enemies that help control them in their homeland. Non-native Invasive Plants and Common Look-alikes

They grow rapidly, reproduce profusely, and compete with native plants for water, light and nutrients. Some of these invasive weeds have been designated as noxious by California law, requiring control efforts by property owners.

Non-native invasive plants tend to outcompete native plants, especially where lands have been disturbed. When they Graphic Design displace native plants and animals, they lower diversity, Annaliese Miller reduce hunting and fishing potential, change the aesthetics Illustrations © Annaliese Miller of a habitat, inhibit recreational activities and tourism, crowd out endangered species, and reduce forage value. For Photography courtesy of: example, tall whitetop, which grows along the Wild and Jim Belsher-Howe, Robin Breckenridge, Scenic Middle Fork of the Feather River, outcompetes Beth Brenneman, Karen Callahan, Michael Charters, other riparian species, creating dense monocultures. Tall Joe DiTomaso, Susan Donaldson, Tim Hanson, whitetop also has extensive but easily-broken root systems, Japhia Huhndorf, Lawrence Janeway, Annaliese Miller, which cause soil destabilization, streambank erosion, and Gary Monroe, Keir Morse, Susi Urie, Kathy VanZuuk, can threaten water quality. Charles Webber, Kathy Welch, Melanie Williams

If you find an invasive weed, please report the infestation Text to the appropriate Plumas National Forest Ranger District Susan Donaldson, Susi Urie, Japhia Huhndorf office or County Agriculture Department. (See contact information on back page.) United States Forest Service Publication R5-TP-036, 2014 Plumas National Forest

Produced in cooperation with the USDA Forest Service, which is an equal opportunity service provider and employer. Adapted with permission from “Invasive Weeds of the Lake Tahoe Basin”, S. Donaldson, University of Nevada Cooperative Extension SP-09-06 copyright 2009.

1 1 Preventing the Spread of Weeds How to Use the Guidebook Prevention is the least expensive and most effective way to This guidebook will help you identify the invasive plant halt the spread of noxious and invasive weeds. species threatening the Plumas National Forest. Compare This requires: invasive plants with common “look-alikes” to help you dif- • Educating workers and the public about the ferentiate between desirable native plants and non-native importance of managing weeds on an ongoing basis invasive plants. • Properly identifying weed species Look for these face icons at the top of the page. • Avoiding or treating existing weed populations • Preventing weed seeds or other plant parts from  = Non-native invasive plants establishing new or bigger populations  = Desirable look-alikes (native and non-invasive) Steps you can take:  = Plants that could potentially become invasive. 1. Use this book to identify invasive weeds in your area. (You may choose to avoid planting species that 2. Inspect your work or play area. Identify any invasive weeds; may become invasive on your property.) map the location of the weeds. The California Invasive Plant Council (Cal IPC) has assigned 3. Clean vehicles, shovels and other soil-disturbing equipment overall threat rankings to weed species: High, Moderate, prior to entering a site to avoid introducing weeds. and Limited. These rankings, as well as California’s state 4. Don’t introduce weed-contaminated soil, fill, or other noxious weed ratings below, are provided for each species. materials to new sites. Use certified weed-free products. “A” rated: very invasive, but have a limited distribution 5. Check shoes, clothing, bicycles and vehicles regularly throughout the state and are considered top priority for weed seeds or other plant parts. Carefully remove for control before they become widespread. and dispose of weedy materials. “B” rated: very invasive and more widespread. Priority 6. Pressure-wash vehicles and equipment after driving of “B” rated weed treatment is decided on a in weedy areas. Periodically monitor and treat areas case- by-case basis depending on the local value of to prevent weedy plants from establishing. resource being compromised, local distribution, and 7. Establish a decontamination area such as a tarp for funds available. cleaning clothing and equipment. “C” rated: generally spread beyond the point where the 8. Don’t walk, ride or drive through infestations. When state of California can justify spending limited operating vehicles, stay on established roads or trails. resources, but the private citizen may control them 9. If dogs accompany you, check their paws and coats on their own. for weed seeds and other plant parts and remove them. Relative abundance of each species is also provided. 10. Don’t plant invasive weeds in your garden or landscape. Common: Found at numerous locations in the area 11. Get advice for treatment on private property from your Moderate: Found at several locations; large local county agriculture department. (See contact information populations may occur at a few locations on back page.) Infrequent: Only at one or a few locations; no large populations 2 3 INDEX COMMON NAME Scientific Name CODE Page INDEX COMMON NAME Scientific Name CODE Page

THISTLES AND LOOK-ALIKES MUSTARDS AND LOOK-ALIKES  Invasive  Invasive BULL THISTLE Cirsium vulgare CIVU 10-11 DYER’S WOAD Isatis tinctoria ISTI 46-47 CANADA THISTLE Cirsium arvense CIAR4 12-13 HOARY CRESS Lepidium draba LEDR 48-49 ITALIAN THISTLE Carduus pycnocephalus CAPY2 14-15 TALL WHITETOP Lepidium latifolium LELA2 50-51 MUSK THISTLE Carduus nutans CANU4 16-17  Look-alike SCOTCH THISTLE Onopordum acanthium ONAC 18-19 YARROW Achillea millefolium ACMI2 52-53  Look-alike TOADFLAXES AND LOOK-ALIKES ANDERSON’S THISTLE Cirsium andersonii CIAN 20-21 Invasive SNOWY THISTLE CIOCC 22-23 

Cirsium occidentale var. candidissimum DALMATIAN TOADFLAX LIDAD 54-55 Linaria dalmatica ssp. dalmatica KNAPWEEDS AND LOOK-ALIKES YELLOW TOADFLAX Linaria vulgaris LIVU2 56-57  Invasive  Look-alike DIFFUSE KNAPWEED Centaurea diffusa CEDI3 24-25 SNAPDRAGON Antirrhinum majus ANMA3 58-59 RUSSIAN KNAPWEED Acroptilon repens ACRE 26-27 BROOMS SPOTTED KNAPWEED CESTM 28-29 Centaurea stoebe ssp. micranthos  Invasive FRENCH BROOM Genista monspessulana GEMO3 60-61  Look-alike SCOTCH BROOM Cytisus scoparius CYSC4 62-63 AMERICAN-ASTER Symphyotrichum spp. 30-31 SPANISH BROOM Spartium junceum SPJU2 64-65 YELLOW ASTERS  Invasive GRASSES MALTA STARTHISTLE Centaurea melitensis CEME2 32-33  Invasive BARBED GOATGRASS Aegilops triuncialis AETR 66-67 YELLOW STARTHISTLE Centaurea solstitialis CESO3 34-35 JOINTED GOATGRASS Aegilops cylindrica AECY 68-69 RUSH SKELETONWEED Chondrilla juncea CHJU 36-37 MEDUSAHEAD Elymus caput-medusae ELCA13 70-71 STINKWORT Dittrichia graveolens DIGR3 38-39 Look-alike  Look-alike  SQUIRRELTAIL Elymus elymoides ELEL5 72-73 TARWEED Madia spp. 40-41 OTHERS

BLACKBERRIES  Invasive  Invasive TREE OF HEAVEN Ailanthus altissima AIAL 74-75 HIMALAYAN BLACKBERRY Rubus armeniacus RUAR9 42-43 SULFUR CINQUEFOIL Potentilla recta PORE5 76-77  Look-alike  Look-alike CALIFORNIA BLACKBERRY Rubus ursinus RUUR 44-45 SLENDER CINQUEFOIL Potentilla gracilis POGR9 78-79 4 5 QUICK REFERENCE ID QUICK REFERENCE ID

THISTLES Flower Head Leaves KNAPWEEDS Bracts Lower Leaves

Bull Thistle Diffuse rough, Knapweed deeply vase prominent spiny combs lobed veins

Canada Thistle Russian lobed, Knapweed similar to Italian thistle, spiny lobed bracts without spines drop papery

Italian Thistle Spotted lobed, similar to Canada thistle, Knapweed deeply elliptical spiny spots lobed bracts with spines hairy underneath

Musk Thistle midrib, American-aster spp. disk hairless (look-alike) narrow, no spines, entire yellow disk

Scotch Thistle cobwebby oval hairy

Anderson’s Thistle (look-alike) small cylinder flat hairs

Snowy Thistle (look-alike) wooly reflexed bracts hairs

6 7 QUICK REFERENCE ID QUICK REFERENCE ID

YELLOW ASTERS Bracts Stems BROOMS Seed Pods Leaves Stems

Malta French Starthistle Broom lateral short, weak spines spines winged 3 leaflets, round purple tipped midway stem hairy evergreen 8 - 10 ridged

Yellow Starthistle Scotch lateral Broom long, stout spines spines winged straw colored at base stem only 3 leaflets, sharply margins sometimes 5 angled hairy simple YELLOW ASTERS Flowers/Plant Stems

bottom Rush of stem Spanish Skeletonweed with stiff downward Broom mostly smooth, pointing hairless hairs round hairy simple finely ribbed

Stinkwort

sticky-glandular, densely smells of camphor branched

Tarweed (look-alike) open, less dense sticky-glandular branches

8 9 BULL THISTLE Cirsium vulgare CIVU Non-native Invasive

Tops of leaves rough, sandpaper texture

Underside of leaf cottony, prominently raised main vein

1 - 1.5 in

Plant, Brenneman; Flower, Donaldson Plant, Brenneman; Flower, Flower head vase-shaped

Rosette leaves rough, prominent veins Also Known As Common thistle Habitat Meadows, roadsides, disturbed sites  Height: 1 - 6 ft Life Cycle Biennial commonly 2 - 3 ft Flowering Time Mid-July to fall n Stems: spiny and winged Relative Abundance Common n Leaves: sandpaper texture, Plumas NF Distribution Throughout; all ranger districts prominent veins Noxious Weed List California C-rated; Cal IPC: Moderate n Flowers: in clusters at ends of branches n Flower color: pink to purple

10 11 CANADA THISTLE Cirsium arvense CIAR4 Non-native Invasive

Bracts small and flat against head, tips weak

0.5 in Flower head drop-shaped Donaldson

Leaves deeply lobed

 Height: 1.5 - 4 ft, commonly 2 - 3 ft Also Known As Field thistle Habitat Roadsides, rangelands, forests, lawns, n Stems: smooth and ridged gardens, moist and disturbed sites with no spines Life Cycle Perennial n Leaves: smooth and sessile Flowering Time Mid-July to fall n Flowers: multiple Relative Abundance Common small flower heads in Plumas NF Distribution Widespread, most abundant in north; clusters on each stem also in Little Grass Valley Reservoir area n Flower color: Noxious Weed List California B-rated; Cal IPC: Moderate light purple to white

12 13 ITALIAN THISTLE Carduus pycnocephalus CAPY2 Non-native Invasive

Heads cobwebby at base of spines

Bracts with narrow, flat spines T. Hanson T. .5 in Flower head elliptical-shaped Lower surface of leaves Stems narrowly tomentose spiny-winged

 Height: 1 - 6 ft Also Known As C. pycnocephalus ssp. pycnocephalus n Stems: narrowly spiny-winged Habitat Roadsides, rangelands, forests, lawns, gardens, disturbed sites n Leaves: deeply lobed, Life Cycle Annual spine-tipped; upper leaves hairless, lower Flowering Time March to July leaves tomentose/flatly Relative Abundance Infrequent hairy Plumas NF Distribution Feather River Ranger District, lower n Flowers: 2 - 5 flower heads elevations on west side per stem Noxious Weed List California B-rated; Cal IPC: Moderate n Flower color: pink to purple

14 15 MUSK THISTLE Carduus nutans CANU4 Non-native Invasive

Bracts large and spiny; purplish in color

2 - 3.5 in

Flower head disk-shaped

Light-green Rosette leaves hairless, midrib Plant, Miller; Flower, Donaldson Plant, Miller; Flower, light-green midrib, whitish margins

 Height: 1 - 6 ft Also Known As Nodding thistle commonly 3 - 4 ft Habitat Pastures, forest, rangelands, roadsides, waste areas, ditches n Stems: spiny and winged Life Cycle Biennial n Leaves: hairless, prominent light-green midrib Flowering Time Mid-July to fall n Flowers: single, very large Relative Abundance Infrequent flower at end of bent, Plumas NF Distribution Limited east of Lee Summit on naked stem Beckwourth Ranger District n Flower color: deep pink Noxious Weed List California A-rated; Cal IPC: Moderate to purple

16 17 SCOTCH THISTLE Onopordum acanthium ONAC Non-native Invasive

Many spiny, needle-like bracts

Leaves hairy, giving a grayish appearance 1-2 in Flower head flattened globe

Donaldson Stems spiny and winged

Also Known As Winged thistle  Height: up to 10 ft, Habitat Waste areas, roadsides, disturbed commonly 5+ ft soils (the tallest of the thistles) Life Cycle Biennial; rarely annual  Stems: spiny, Mid-July to fall prominently winged Flowering Time Relative Abundance Infrequent  Leaves: hairy and sessile Plumas NF Distribution Beckwourth Ranger District;  Flowers: in groups of 2 or 3 extreme east side on branched tips Noxious Weed List California A-rated; Cal IPC: High  Flower color: purple

18 19 ANDERSON’S THISTLE Cirsium andersonii CIAN Native Look-alike

0.75 - 1.5 in

Brenneman Flower head cylinder-shaped Leaf margins wavy and spiny

Rosette leaves not prominently veined, small flat hairs

Also Known As Rose thistle  Height: 2 - 4 ft Habitat Open places, woodlands, forests n Stems: purplish and Life Cycle Biennial thornless Flowering Time July to fall n Leaves: divided and wavy Relative Abundance Common with spiny margin Plumas NF Distribution Throughout; above 3000 ft elevation n Flowers: single flower at end of stem n Flower color: rose red to reddish purple

20 21 Cirsium occidentale SNOWY THISTLE var. candidissimum CIOCC Native Look-alike

Large reflexed bracts, wooly hairs Plant, Urie; Flower, Monroe Calphotos Plant, Urie; Flower,

3/4 - 2 in

Densely white wooly hairs

Height: 1.5 to 6.5 ft Also Known As None  Habitat Disturbed areas, shrubby areas, n Stems: densely open woodlands white wooly hairs Life Cycle Biennial n Leaves: densely white wooly hairs on both Flowering Time July to September surfaces Relative Abundance Common in Northern California n Flowers: single or in Plumas NF Distribution Throughout; below 6000 ft elevation clusters at the end of branches n Flower color: pink to red

22 23 DIFFUSE KNAPWEED Centaurea diffusa CEDI3 Non-native Invasive

Bract tips spiny; margins divided like teeth of comb

Upper leaves narrow and entire

(Squarrose knapweed, a similar noxious weed, has recurved bract spines.) Donaldson

Stems stiff and widely branching

Lower leaves deeply lobed Also Known As Tumble knapweed  Height: 1 - 2.5 ft Habitat Roadsides, waste areas, dry rangelands, disturbed sites n Stems: rough to touch Life Cycle Annual to short-lived perennial n Leaves: upper, entire; lower, deeply lobed Flowering Time June to August n Growth form: maintains Relative Abundance Infrequent bush shape; after frost, Plumas NF Distribution Not currently known on PNF lands, can break off and tumble but occurs nearby and may invade n Flower color: white to Noxious Weed List California A-rated; Cal IPC: Moderate pale pink

24 25 RUSSIAN KNAPWEED Acroptilon repens ACRE Non-native Invasive

Bract margins papery, NOT spiny

Upper leaves narrow and entire Donaldson

Stems openly branched

Lower leaves lobed

Also Known As Creeping knapweed  Height: 1 - 3 ft, Habitat Roadsides, riverbanks, ditches, generally 2 - 3 ft pastures, waste places n Stems: erect, cobwebby Life Cycle Rhizomatous perennial n Leaves: upper, entire; July to fall Flowering Time lower and rosette, lobed Relative Abundance Infrequent n Growth form: thick Plumas NF Distribution Not currently known on PNF lands, rounded clumps with but occurs adjacent to the extreme drooping branches east side n Root: black below crown Noxious Weed List California B-rated; Cal IPC: Moderate n Flower color: pink to purple

26 27 Centaurea stoebe SPOTTED KNAPWEED ssp. micranthos CESTM Non-native Invasive

Bract tips dark, finely fringed, spineless

Upper leaves narrow and entire Plant, Breckenridge CDFA; Flower, Donaldson Flower, Plant, Breckenridge CDFA;

Lower leaves deeply lobed Stems openly and smooth branched Note leaf placement Also Known As Centaurea maculosa Habitat Disturbed soil, rangelands, pastures, meadows, roadsides, areas with summer rainfall  Height: 1 - 5 ft; generally closer to 3 ft Life Cycle Perennial; sometimes biennial n Stems: erect and rough Flowering Time July to early September n Leaves: upper, linear; Relative Abundance Moderate lower, divided Plumas NF Distribution Throughout; scattered sites on all ranger districts. n Growth form: tall with open branching Noxious Weed List California A-rated; Cal IPC: High n Flower color: pink to purple

28 29 AMERICAN-ASTER Symphyotrichum spp. Native Look-alike

Bracts do not have spines

Donaldson Leaves narrow and entire

Also Known As Most species formerly in the  Height: variable, genus Aster often 1 - 2 ft Habitat Meadows, gardens n Stems: smooth to hairy Life Cycle Annual or perennial n Leaves: upper and lower leaves narrow and entire Flowering Time Late July to fall n Growth form: ranges from Relative Abundance Common short to tall Plumas NF Distribution Different species found throughout area n Flower color: variable, often pink to purple with yellow center

30 31 MALTA STARTHISTLE Centaurea melitensis CEME2 Non-native Invasive

Upper spines and bracts Lateral spines at reddish purple base and middle of main spine

Short, weak spines (Difficult to distinguish from CESO3 when vegetative) T. Hanson T.

Also Known As Tocalote Habitat Roadsides, disturbed areas, grasslands  Height: 0.5 - 3 ft, commonly 2 ft Life Cycle Annual Flowering Time April to August n Stems: winged Relative Abundance Infrequent n Leaves: gray and hairy; upper, entire; Plumas NF Distribution Known from western side of Feather lower, deeply lobed River Ranger District; could be more widespread, but misidentified as n Growth form: stiffly yellow starthistle branching Noxious Weed List California C-rated; Cal IPC: Moderate n Flower color: yellow 32 33 YELLOW STARTHISTLE Centaurea solstitialis CESO3 Non-native Invasive

Lateral spines only at base of main spine

Long, stout, straw-colored spines at tips of bracts (up to 1 in. long) Donaldson

Upper leaves Lower leaves entire deeply lobed

Also Known As None  Height: 0.5 - 5 ft, Habitat Roadsides, waste areas, grasslands commonly 2 ft Life Cycle Annual n Stems: winged Late June to September Flowering Time n Leaves: gray and hairy; Relative Abundance Common upper, entire; Plumas NF Distribution Throughout, especially abundant lower, deeply lobed along highways and near development n Growth form: stiffly Noxious Weed List California C-rated; Cal IPC: High branching n Flower color: yellow

34 35 RUSH SKELETONWEED Chondrilla juncea CHJU Non-native Invasive

Lower 4 - 6 inches of stem has downwardly bent coarse hairs DiTomaso

Rosette leaves sharply toothed

Milky juice in stems and leaves Stems smooth above Also Known As Skeleton weed, hogbite Habitat Roadsides, rangelands, pastures, disturbed soils  Height: 1 - 4 ft Life Cycle Perennial with extensive, deep root n Stems: rigid and wiry; system highly branched; cut Flowering Time Mid-July through frost surfaces exude milky sap Relative Abundance Infrequent n Leaves: upper, narrow Plumas NF Distribution Widely scattered but increasing on and entire, inconspicuous; west side of Feather River Ranger stems often lack leaves District. Also known near Lee n Growth form: bushy Summit and town of Graeagle. n Flower color: yellow Noxious Weed List California A-rated; Cal IPC: Moderate 36 37 STINKWORT Dittrichia graveolens DIGR3 Non-native Invasive

Bracts in Single flower several heads grow at overlapping ends of branches; rows and in leaf axils

Plant sticky-glandular; smells strongly of camphor

(Can cause allergic contact dermatitis; recommend gloves if handling!) Williams

Seed ~ 1/8 in. long

 Height: 0.5 - 3 ft None Also Known As n Stems: many-branched, Habitat Meadows, roadsides, waste places, sticky-glandular gardens n Leaves: narrow, alternate, Life Cycle Annual reduced upwards, and Flowering Time September to November sticky-glandular Relative Abundance Moderate n Flower heads: single flower heads grow at Increasing in the North Fork Feather Plumas NF Distribution ends of branches; and in River canyon, also scattered on west leaf axils side of Feather River Ranger District n Flower color: yellow Noxious Weed List California-NO; Cal IPC: Moderate 38 39 TARWEED Madia spp. Native Look-alike

M. gracilis M. glomerata Flowers small, spaced widely or in tight clusters, depending on species

bracts in single row Plant sticky-glandular

Seed M. gracilis , Huhndorf; glomerata Janeway

Madia gracilis

 Height: M. gracilis: 0.2 - 3 ft M. glomerata: 0.2 - 4 ft M. gracilis n Stems: lower/inner stems Also Known As Madia (several common species) hairy; upper/outer stems Habitat Meadows, open and disturbed places sticky glandular (both spp.) Life Cycle Annual n Leaves: narrow to linear, Flowering Time M. gracilis: April - July sticky-glandular M. glomerata: June - August n Flower heads: Relative Abundance Common M. gracilis: in open clusters, M. glomerata: tightly Plumas NF Distribution Throughout; common on all clustered ranger districts n Flower color: yellow

40 41 HIMALAYAN BLACKBERRY Rubus armeniacus RUAR9 Non-native Invasive

3 - 5 leaflets

Stems 5-angled Huhndorf

Stout, recurved spines

Also Known As Rubus discolor  Height: up to 8 ft, Habitat Roadsides, riparian areas, especially when mounded and disturbed sites on old canes Life Cycle Perennial, each cane lives 2 years n Stems: 5-angled, with stout, recurved spines Flowering Time April to July n Leaves: 3 - 5 leaflets, Relative Abundance Common white underneath Plumas NF Distribution Throughout, very common along the North Fork Feather River, its n Flowers: large clusters at tributaries, and Portola area the end of branches Noxious Weed List California B-rated; Cal IPC: High n Flower color: pink 42 43 CALIFORNIA BLACKBERRY Rubus ursinus RUUR Native Look-alike

Usually 3 leaflets

Many slender, straight prickles

Stems round Plant, Huhndorf; Flower, Callahan; Leaf Huhndorf Plant, Huhndorf; Flower,

Height: generally up to 1 ft; Also Known As Pacific blackberry  stems longer but Habitat Forests, openings, disturbed areas low-growing Life Cycle Perennial, each cane lives 2 years n Stems: round, with many Flowering Time March to July slender, straight prickles Relative Abundance Common n Leaves: Usually 3 leaflets, Plumas NF Distribution Throughout; all ranger districts green underneath n Flowers: 1 - 5 flowers per cluster n Flower color: white

44 45 DYER’S WOAD Isatis tinctoria ISTI Non-native Invasive

Mature fruits black to dark purple; hang like pendants from stem

Tiny 4-petaled flowers in dense clusters near ends of branches Plant, Welch; Flower, Belsher-Howe Flower, Plant, Welch; Lobes clasp stem on upper leaves

Long petiole on Rosette leaves rosette leaves oblanceolate with weakly rounded tips Also Known As Marlahan mustard Habitat Meadows, roadsides,  Height: up to 4 ft streambanks, rangelands n Stems: single stem gives Life Cycle Biennial to short lived perennial rise to multiple branches Flowering Time June to July with multiple flower clusters Relative Abundance Infrequent n Leaves: blue-green foliage Plumas NF Distribution Mt Hough and Beckwourth Ranger with cream-colored midrib; Districts. Known from near Cooks upper leaves clasp stem, Creek, Indicator Peak, Doyle Crossing, arrowhead-shaped; and occasional along Hwy 70. lower leaves petiolate Noxious Weed List California B-rated; Cal IPC: Moderate n Flower color: yellow 46 47 HOARY CRESS Lepidium draba LEDR Non-native Invasive

One branch

Tiny 4-petaled flowers in dense clusters near ends of branches 2 lobes Donaldson Note: There are three very similar clasp stem on noxious weed species that can only be distinguished in fruit. upper leaves L. draba = heart pod L. appelianum = globe pod L. chalepense = lens pod Leaves lance-shaped

Also Known As Whitetop, short whitetop, Cardaria draba  Height: up to 2 ft Habitat Meadows, fields, roadsides, ditches, commonly 1 ft streambanks, rangelands n Stems: many stems give Life Cycle Rhizomatous perennial rise to multiple branches with one flower cluster Flowering Time May to June Leaves: blue-green foliage; Relative Abundance Infrequent n upper leaves clasp stem; Plumas NF Distribution Scattered on Mount Hough Ranger lower leaves petiolate District and around Portola, but not on Beckwourth Ranger District n Seed shape: round Noxious Weed List California B-rated; Cal IPC: Moderate n Flower color: white 48 49 TALL WHITETOP Lepidium latifolium LELA2 Non-native Invasive

Multiple branches

Tiny 4-petaled flowers in dense clusters near ends of branches Donaldson Stems branch from junction of leaf with main stem Leaves lance-shaped; leaf margins smooth or toothed

 Height: 1 - 6 ft Also Known As Perennial pepperweed commonly 3+ ft Habitat Riparian areas, floodplains, meadows,  Stems: each stem gives seasonally wet areas, roadsides rise to multiple branches with multiple flower clusters Life Cycle Rhizomatous perennial  Leaves: upper leaves, sessile; Flowering Time Late June to August lower leaves, petiolate; Relative Abundance Moderate basal leaves, much larger Plumas NF Distribution Throughout; scattered on all than upper leaves ranger districts n Seed shape: round Noxious Weed List California B-rated; Cal IPC: High n Flower color: white 50 51 YARROW Achillea millefolium ACMI2 Native Look-alike

Flower heads flattened, dome-shaped corymbs

Leaves hairy and very finely pinnately

Plant, Brenneman; Flower, Donaldson Plant, Brenneman; Flower, divided, appearing feather-like

Also Known As Common yarrow, milfoil Habitat Gardens, meadows, grasslands, forests

Life Cycle Perennial  Height: 2 - 3 ft Flowering Time June to September n Stems: hairy-wooly Relative Abundance Common n Leaves: feather-like; evenly Plumas NF Distribution Throughout; common on all distributed along stem; ranger districts lower leaves larger n Flower color: white or pink

52 53 Linaria dalmatica DALMATIAN TOADFLAX ssp. dalmatica LIDAD Non-native Invasive

Leaves ovate, Spurs long, tips pointed somewhat curved or straight Donaldson

Flowers borne in axils of upper leaves and bracts

Leaves clasp stem Also Known As Wild snapdragon, Linaria genistifolia ssp. dalmatica  Height: up to 3 ft Habitat Roadsides, pastures, rangelands,  Stems: erect and branched cultivated fields  Leaves: ovate, alternate Life Cycle Perennial and entire; succulent and Flowering Time July to fall waxy Relative Abundance Infrequent  Growth form: more Plumas NF Distribution Known from Murdock Crossing on scattered than yellow Beckwourth Ranger District and near toadflax Wolf Creek on Mt Hough Ranger District  Flower color: yellow, with Noxious Weed List California A-rated; Cal IPC: Moderate orange, bearded throat

54 55 YELLOW TOADFLAX Linaria vulgaris LIVU2 Non-native Invasive

Spur Plant, Brenneman; Flower, Charles Webber © CA Academy Charles Webber Plant, Brenneman; Flower, of Sciences

Leaves linear, pointed at both ends Leaves alternate, crowded close together

Also Known As Butter and eggs  Height: 1 - 2 ft; shorter than dalmatian Habitat Rangelands, roadsides, waste places, cultivated fields toadflax Life Cycle Perennial  Leaves: linear, smooth to sparsely hairy; succulent Flowering Time July to fall and waxy Relative Abundance Moderate  Growth form: tends to Plumas NF Distribution Not currently known on PNF lands grow in crowded patches Noxious Weed List California-NO; Cal IPC: Moderate  Flower color: yellow, with orange, bearded throat

56 57 SNAPDRAGON Antirrhinum majus ANMA3 Non-native Look-alike

Flowers in terminal racemes

No spur Plant, Brenneman; Flower, Donaldson Plant, Brenneman; Flower,

Upper leaves long and narrow Lower leaves lanceolate

Also Known As None Habitat Ornamental gardens Life Cycle Annual to perennial  Height: 0.5 - 3 ft June to fall Flowering Time n Leaves: upper, long and Relative Abundance Occasionally escaped from cultivation narrow; lower, lanceolate; Plumas NF Distribution Not naturalized on PNF lands; soft, not waxy common garden flower n Flowers: fuzzy-hairy

n Flower color: yellow, but other colors are available

58 59 FRENCH BROOM Genista monspessulana GEMO3 Non-native Invasive

Flowers 4 -10 in clusters at ends of short branchlets

Small pea flowers

Upper lip 2-lobed to near middle Plant, Huhndorf; Flower, Belsher-Howe Plant, Huhndorf; Flower, Seed pods slightly flattened, densely covered with long hairs Calyx 2-lipped, hairy 3 leaflets, Lower lip shallow, hairy 1 - 3 lobed Also Known As Soft broom, canary broom, Montpelier broom  Height: woody shrub, Habitat Roadsides, forests and rangelands up to 8 ft Life Cycle Long lived perennial n Stems: 8 - 10 ridges; round cross-section Flowering Time May to July Relative Abundance Infrequent n Branches: dark green, twigs silvery-silky-hairy Plumas NF Distribution Feather River and Mt Hough Ranger Districts; abundant on far west side n Leaves: 3 leaflets, usually and occurs in North Fork Feather dense; evergreen River canyon n Flower color: yellow; Noxious Weed List California C-rated; Cal IPC: High slight fragrance 60 61 SCOTCH BROOM Cytisus scoparius CYSC4 Non-native Invasive

Flowers single or paired in leaf axils

Numerous showy pea flowers

Seed pods flattened, only margins hairy

Plant, VanZuuk; Flower, Morse Flower, Plant, VanZuuk; Top lip minutely toothed

Calyx 2-lipped, 3 leaflets, smooth sometimes simple

Stems 5-angled Also Known As Common broom, English broom  Height: woody shrub Habitat Pastures, forests, disturbed areas up to 8 ft Life Cycle Long lived perennial n Stems: 5-angled; star-shaped cross-section Flowering Time May to July n Branches: dark green; Relative Abundance Moderate more-or-less erect Plumas NF Distribution Known on all ranger districts; abundant on far west side, occurs n Leaves: 3 leaflets, in North Fork Feather River canyon, sometimes simple on scattered on far east side new twigs, deciduous Noxious Weed List California C-rated; Cal IPC: High n Flower color: deep yellow; slight to no fragrance

62 63 SPANISH BROOM Spartium junceum SPJU2 Non-native Invasive

Flowers in open racemes at stem tips

Numerous showy pea flowers Seed pods slightly flattened, densely covered with long hairs Donaldson

Stems round in cross-section Calyx 1-lipped, smooth Leaves simple

Also Known As Weaver’s broom Habitat Roadsides, forests and rangelands  Height: woody shrub up to 8 ft Life Cycle Long lived perennial n Stems: smooth or finely Flowering Time May to July ribbed; round cross-section Relative Abundance Infrequent n Branches: dark green; Plumas NF Distribution Occasional on western edge of more-or-less erect Feather River Ranger District  Leaves: simple, entire; Noxious Weed List California C-rated; Cal IPC: High sparse and deciduous n Flower color: yellow; strong fragrance

64 65 BARBED GOATGRASS Aegilops triuncialis AETR Non-native Invasive

3 long, straight awns

Huhndorf Spikelet

Seed head

Fertile spikelets Spikelet occur at base of plant in addition to seed heads Also Known As None Habitat Rangelands, roadsides, disturbed places  Height: 1 - 2 ft Life Cycle Annual  Seed head: spikelets fall Flowering Time May to July from plant intact, not Relative Abundance Moderate leaving a central axis Plumas NF Distribution Feather River and Mount Hough  Awns: each spikelet has Ranger Districts; roadsides; North 3 long straight awns Fork Feather River canyon and  Growth form: ranges from occasional on far west side a single stem to a bunch Noxious Weed List California-NO; Cal IPC: High with many stems 66 67 JOINTED GOATGRASS Aegilops cylindrica AECY Non-native Invasive

Short awns

Each spikelet Spikelet will fall separately

Seed head narrow, cylindrical Spikelet Huhndorf

Spikelets at base of plant less common than in barbed goatgrass

Spikelet Also Known As None Habitat Roadsides, disturbed, dry places, cultivated fields  Height: 1 - 2 ft Life Cycle Annual  Seed head: spikelets fall Flowering Time May to July from plant intact, not Relative Abundance Infrequent leaving a central axis Plumas NF Distribution Mount Hough and Feather River  Awns: very short except Ranger Districts; known along Hwy 70 for on the top spikelet corridor and suspected in Sierra  Growth form: ranges from Valley near Beckwourth Ranger District a single stem to a bunch Noxious Weed List California-NO; Cal IPC: None with many stems 68 69 MEDUSAHEAD Elymus caput-medusae ELCA13 Non-native Invasive

Upper awns

Lower Seed awns head Huhndorf

Awn

When mature, seeds fall from the head, leaving long awns in place

Central axis Seeds

Also Known As Taeniatherum caput-medusae  Height: 1 - 2 ft Habitat Rangelands, roadsides,  Seed head: central axis with disturbed places awns persists into winter Life Cycle Annual  Awns: upper are long and Flowering Time April to July wavy; lower are shorter Relative Abundance Common  Growth form: ranges from a single stem to a bunch Plumas NF Distribution Throughout; common in disturbed areas of all ranger districts with many stems Noxious Weed List California-NO; Cal IPC: High  Key feature: very long, upward-pointing, wavy awns 70 71 SQUIRRELTAIL Elymus elymoides ELEL5 Native Look-alike

Seed head When mature, seed heads break Many awns, apart into sections,

Huhndorf approximate not leaving a central equal length axis behind

Young Awn seed head

 Height: 1 - 2 ft  Seed head: spikelets fall Also Known As Bottlebrush from plant intact, not Habitat Forests, grasslands, most plant leaving a central axis communities  Awns: approx. equal length; Life Cycle Perennial often reddish when young, Flowering Time June to August straw-colored when mature Relative Abundance Common  Growth form: generally in bunches with several to Plumas NF Distribution Throughout; common in all ranger districts many stems  Key feature: awns bent to nearly horizontal when mature 72 73 TREE OF HEAVEN Ailanthus altissima AIAL Non-native Invasive Plant, Williams; Flower, T. Hanson T. Plant, Williams; Flower, Teeth Top of leaflet Underside Opposite leaflets Gland-tipped teeth at the base of each leaflet Leaf distinguish from sumac, which looks similar when young Fruit with seed near middle, clusters of 1 - 5 Sapling Also Known As Stink tree Habitat Disturbed areas, riparian areas,  Height: tree up to 60 ft often near old habitations n Bark: smooth and pale gray

Life Cycle Tree; perennial n Leaves: up to 3 ft long, Flowering Time June with 11 - 25 leaflets; Relative Abundance Infrequent foul-smelling when crushed Plumas NF Distribution Feather River and Mount Hough n Flower color: greenish Ranger Districts; occasional in the n Fruits: clusters of North Fork Feather River canyon reddish-brown winged Noxious Weed List California C-rated; Cal IPC: Moderate fruits in September 74 75 SULFUR CINQUEFOIL Potentilla recta PORE5 Non-native Invasive

Flowers 5 petals

Stems branch only in the inflorescence Bud

Both long spreading and very short hairs DiTomaso

Leaves palmately compound with 5 - 7 divisions (6 - 7 common)  Height: 2 ft Also Known As Roughfruit cinquefoil n Stems: hairs glandular, Habitat Roadsides, pastures, rangeland, (Difficult to ID, almost appearing shiny wildlands, disturbed areas consult an expert) n Leaves: upper and lower Life Cycle Tap-rooted perennial surfaces stiff-hairy; Flowering Time May to July undersides green (not silvery like most potentillas); Relative Abundance Infrequent hairs glandular, almost Plumas NF Distribution Occasional throughout but not well appearing shiny documented n Growth form: shrub Noxious Weed List California-NO; Cal IPC: None n Flower color: light yellow 76 77 SLENDER CINQUEFOIL Potentilla gracilis POGR9 Native Look-Alike

Flowers 5 petals

Bud

Hairs of only one

Plant, Charters, CalPhotos; Flower, DiTomaso Plant, Charters, CalPhotos; Flower, length

Leaves palmately compound with 5 - 7 divisions

Also Known As Graceful cinquefoil, western cinquefoil  Height: up to 2.5 ft Habitat High mountain meadows, open forests  Stems: have hairs of only one length Life Cycle Perennial Flowering Time June to August  Leaves: hairy, especially below; undersides Relative Abundance Common gray-green, silvery; leaf Plumas NF Distribution Throughout; all ranger districts margins evenly toothed  Flower color: yellow

78 79 GLOSSARY GLOSSARY Alternate: Borne singly and changing sides at each node, Ovate Leaf: Egg-shaped leaf that is attached at the broad end. such as leaves. Palmate: Having three or more veins or lobes radiating Awn: A thin, bristle-like extension, often part of a grass from a central point, similar to the fingers on a hand. seed head. Panicle: A branched inflorescence in which the flowers Axil: The angle formed between the stem and any part, bloom from the bottom up. such as a leaf, attached to it. Petiole: The stalk of a leaf. Bract: A modified leaf at the base of a flower. Pinnate: A compound leaf with leaflets arranged on op- Corymb: A flat-topped or round-topped arrangement of posite sides of the axis. flowers where the lower flower stalks are longer than the Raceme: A simple, elongated arrangement of flowers. upper stalks. Ray flower: Long, narrow flower that radiates outward Cyme: A branched inflorescence in which the terminal from central disk flowers in the Asteraceae family. Each flower blooms first. ray flower resembles a single petal. Disk flower: The tiny, tubular flower of the Asteraceae Rhizomatous: Having rhizomes, or horizontal underground that forms the center disk of the flowerhead. stems that produce shoots above and roots below. Divided: Deeply lobed leaf in which lobes are indented to Rosette: A dense, basal cluster of leaves arranged in a the base or the midrib. circular fashion around one point, usually at ground level. Elliptic: Shaped like an ellipse or a narrow oval, broadest Serrate: With sharp teeth directed forward; generally in the middle. refers to leaf edges. Entire: The margins are smooth, without teeth or lobes. Sessile: Without a stalk of any kind; for example, a leaf Inflorescence: A flower cluster. directly attached to a stem. Linear: Narrow and flat with sides or edges parallel, as Spike: An unbranched, long flower stalk in which the in a leaf. flowers attach directly to the stem and mature from the Lobed: Bearing lobes cut less than halfway to base or midvein. bottom upwards. Margin: The outer edge of the leaf, which may be Spikelet: in grasses, the basic unit of the seed head, smooth, serrated, lobed, etc. sometimes falling intact from plant. Midrib: The middle vein of a leaf. Toothed: Having sharp points or lobes along a margin, as on a leaf. Oblanceolate: leaf shape in which the length is at least Tomentose: Covered with dense, generally flattened and 3x longer than wide, but broadest above middle. matted hairs. Oblong: Leaf shape in which the leaf is two to four times Umbel: A flat-topped flower cluster with all branches longer than it is wide, with nearly parallel sides. attached at the same point. Opposite: Leaves or other structures borne across from Winged stem: A stem with one or more thin, flat each other at the same node. margins protruding along the length of the stem. 80 81 WEED MAPPING CONTACT INFORMATION

The Plumas-Sierra Weed Management Group and the For weed information and mapping on the Plumas Plumas National Forest have been mapping weeds since National Forest, contact District Botanists: 2001. Regular mapping and inventory helps us determine Beckwourth Ranger District (Blairsden): which species are present in the area, what management (530) 836-7167 methods are appropriate, and whether management has Mount Hough Ranger District (Quincy): been a success. We can also track patterns of spread and (530) 283-7657 plan preventive practices. Feather River Ranger District (Oroville): We welcome your mapping information, for the species (530) 532-7417 in this guide and/or any other species rated as “High” by Cal-IPC or “A” by California. For weed control information on private land contact: Please include: Butte County Agriculture Department (530) 538-7381 • the date surveyed Plumas/Sierra County Agriculture Department • the weed name and code (preferably the (530) 283-6365 scientific name) • the location of the observation using UTMs Funded by: if available. If using a global positioning system (GPS) unit, set your meter to datum NAD83. • a thorough description of the location • the size of the infestation in square feet or acres

• the density of the infestation (number of plants Adapted with permission from “Invasive Weeds of the or estimated percent cover) Lake Tahoe Basin”, S. Donaldson, University of Nevada • any control methods you employed Cooperative Extension, SP-09-06, copyright 2009.

Please do not take any management actions or remove plants until they have been positively identified. Consult your county or Plumas National Forest weed contact for assistance.

Forward the data to the appropriate contact. See listings Illustrations © 2013, Annaliese Miller Contact her at: [email protected], aninau.com on next page.

Printed on Recycled Paper

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