Download SPOTTER`S NETWORK Aboriginal People and Invasive Plants Plant

SPOTTER’S NETWORK
Aboriginal People and Invasive Plants
Plant Notes
ASPARAGUS (Asparagus officinalis)
Identification:
• ID KEY: Stems covered in stiff hairs with swollen reddish to black bases where
attached to stem that form noticeable flecks. Hairs are painful to the touch.
• Perennial
• Fleshy and unbranched stems when young, freely branching and fern-like with
age
• Leaves are short and scaly
• Growing to 1 to 1.5 m tall
• Flowers are small, greenish white and bell-shaped
• Flowers hang downwards on slender stalks
• Red hanging berries
Habitat: Asparagus grows in moist disturbed sites near settled areas.
Origin: Europe/Asia
Distribution: Asparagus is scattered and is locally common, mostly at low elevations in
Thompson and Okanagan plateaus and basins and southern Rocky Mountain Trench.
Spread: Asparagus is an escapee from cultivation.
Impacts/Uses: Used in the treatment of rheumatism and as a food source.
(GREAT) MULLEIN (Vebascum thapsus)
Identification:
• ID KEY: Large, soft, very hairy leaves.
• Biennial, deep taprooted, lives for two years
• Basal rosette to 60 cm in diameter in first year
• Growing to 2 metres tall
• Flowers are yellow and are in large terminal spikes (second year)
Habitat: Common mullein grows in disturbed, often gravelly sites, fields and pastures at
low to mid elevations in British Columbia.
Origin: Europe/Asia
Distribution: Common Mullein is in the central and south central areas of the province,
including the coastal region.
Other: It is a very minor problem for most agricultural crops, since it is not a very
competitive species, being intolerant of shade from other plants and unable to survive
tilling.
1 Spread: Spread by seed, usually no further than 1m. Common Mullein seed bank is
persistent. Some research shows that seeds have germinated after 100 years or more in
the soil.
Impacts/Uses: May have traditionally been used as a medicinal herb used to treat a
variety of ailments ranging from coughs to earaches.
PURPLE LOOSESTRIFE (Lythrum salicaria)
Identification:
• ID KEY: Has stiff, four-sided stems ending in spikes of showy purple flowers
• Perennial or woody half-shrub growing 1-3 m tall
• Woody taproot with fibrous branching root system
• Short, narrow leaves that are stalkless
• Plants become taller and bushier over the years with a maturing rootstock
• Sometimes confused with fireweed (Epilobium angustifolium)
Habitat: Purple loosestrife grows in wetlands, stream banks, ditches, irrigation canals,
marshes, stream and lake shorelines and shallow ponds at low to mid elevation in BC.
Origin: Europe – escaped ornamental
Distribution: Purple loosestrife occurs in the Fraser Valley and in isolated infestations on
Vancouver Island, Okanagan, Cariboo and East and West Kootenay regions.
Other: It can form dense stands that reduce plant and animal diversity in wetland
ecosystems.
Spread: Purple loosestrife reproduces by seed (one plant can produce over 300,000
seeds) which are mainly distributed by water; however, they can also be dispersed by
animals and humans.
Impacts/Uses: It affects fish habitat, by increasing sediment into stream and rivers.
Reduces wetlands areas where many medicinal plants are harvested. Also reduces
wetland forge sites for moose that graze along wetlands banks; may have been used
for medicinal purposes.
RUSH SKELETONWEED (Chondrilla juncea)
Identification:
• ID KEY: Stems are covered with stiff hairs that are downward pointing
• Taprooted perennial growing to 1.3 m in height
• Branched wiry stems covered with stiff, reddish-brown downward pointing hairs
at the base
• Stems have a milky juice
• Very small leaves give plant a "skeleton-like” appearance
• Small yellow flowers
• Early growth is a rosette of dandelion-like leaves that wither once the plant
flowers
2 Habitat: Rush skeletonweed occupies rangelands, roadsides, and disturbed habitats at
mid-elevations in the dry grassland zone.
Origin: Europe/Asia/North Africa
Distribution: Infestations occur in the Vernon area, Crescent Valley, Kimberley,
Windermere, and Creston. It is a major concern in the Kootenay and Okanagan
regions.
Other: Infestations of Rush Skeletonweed can reduce livestock and wildlife forage and
the latex in the stems causes serious problems with harvest machinery.
Spread: New plants arise from lateral root buds in upper 0.6 m of soil. A single plant may
produce as many as 20,000 parachute-like seeds which are dispersed by wind, water,
animals, and humans.
Impacts/Uses: Can infest forging sites for deer, elk and moose. With reduced forage,
wildlife are forced to feed further away from traditional hunting and trapping sites.
DIFFUSE KNAPWEED (Centaurea diffusa)
Identification:
• ID KEY: Flower-heads with small, sharp, rigid spines Thought to be hybridizing with
spotted knapweed making identification difficult at times, but can be identified
from other knapweed spp. by the terminal spine on the floral bract, occasionally
has pink flowers
• Biennial to short-lived perennial, first year in a basal rosette, see top left of slide
• Heavily branched, taprooted
• Grows to 0.6 to 1 m in height
• Divided leaves grayish-green in colour, hairy
Habitat: Diffuse knapweed occurs on dry and disturbed sites, over grazed areas, and
areas with poor soil quality.
Origin: Europe
Distribution: Diffuse knapweed is well established in many regions of southern BC
Other: Diffuse Knapweed is one of 13 "knapweed" species in British Columbia.
Spread: By seeds.
Impacts/Uses: Diffuse knapweed is highly competitive, it reduces productivity of
rangeland and quickly invades disturbed native plant communities thus reducing
biodiversity, and increasing soil erosion. It emits a toxin called catechin into the soil,
which can kill native plants.
SPOTTED KNAPWEED (Centaurea biebersteinni)
Identification:
• ID KEY: Flower-head bracts have a black-tipped fringe that gives a spotted
appearance
• Biennial or short-lived perennial
• Grows to a height of 1.5 m and has a stout taproot
3 •
Hairy, deeply-cut leaves and purple (or occasionally white) flowers on one or
more upright stems
Habitat:
Spotted knapweed is widespread at low to mid-elevation grasslands and dry open
forests.
It has adapted to well-drained soils and can survive in very dry climates such as those of
Ashcroft and Osoyoos, shade intolerant.
Origin: Europe
Distribution: Spotted knapweed occurs frequently in southern British Columbia east of
the Coast-Cascade Mountains and is present on Vancouver Island and the mainland. It
is a major concern in the Kootenay, Okanagan, Thompson, Cariboo, Omineca, and
Peace River regions.
Other: Diffuse Knapweed is one of 13 "knapweed" species in British Columbia.
Spread: This species is prolific, with individual plants producing up to 140,000 seeds per
square metre. Although seeds are shed in the immediate area around the parent plant,
they are often spread much more widely in hay and on vehicle undercarriages.
Impacts/Uses: Spotted knapweed is a highly competitive weed that reduces or
displaces desirable forage in disturbed areas, and sometimes invades adjacent areas
that are relatively undisturbed. It forms near monocultures in some areas of British
Columbia. Spotted knapweed is allelopathic; it releases a chemical (catechin) in the
soil preventing other plants from growing. Contact with this plant can cause skin
irritation.
SULPHUR CINQUEFOIL (Potentilla recta)
Description:
• ID KEY: It has distinctive hairy leaves divided into five to seven separate, toothed
leaflets growing on one or several stems
• Perennial member of the Rose family
• Flowers have five, sulphur-coloured, heart-shaped petals
• Mature plants grow 0.3 to 0.8 m in height
• Sulphur cinquefoil is most often confused with graceful cinquefoil, a native
species which has wooly white hairs on the underside of leaves, more basal
leaves, bright yellow flowers, and is shorter in stature
Habitat: Adapted to a wide range of soils and climates, but currently is mostly restricted
to the grasslands and dry forest zones in BC.
Origin: Europe/Asia
Distribution: It is common in southern BC, and considered a major concern in the
Kootenay, Okanagan, and Thompson agricultural areas.
Spread: Seeds are dispersed by birds, animals, and livestock, either through digestion or
by being picked up on hooves or in hair. Plants also spread through roots.
Impacts/Uses: Sulphur cinquefoil is unpalatable to grazing animals and very
competitive with native plants, resulting in reduced forage for livestock and wildlife on
rangelands and pastures.
4 DALMATIAN TOADFLAX (Linaria genistifolia spp. dalmatica)
Identification:
• ID KEY: Flowers are bright yellow and resemble snapdragons.
• Common (Yellow) toadflax is similar but has more linear, pointed leaves that do
not clasp the stem.
• Broad, waxy leaves that clasp the stem
• Grows up to 1.2 m tall
Habitat: Grows in grasslands, forest-grasslands, and disturbed areas
Origin: Europe
Distribution: Grows throughout BC.
Other: Introduced as a garden ornamental.
Spread: By seeds and vegetatively from roots; a mature plant can produce up to
500,000 seeds annually. Seeds remain viable for up to 10 years. Dispersal probably
occurs as seed pass through the gut or are caught in the hair of animals, as well as by
birds and water.
Impacts/Uses:
May have been used to treat boils, as an insecticide, as a yellow dye
May have been used for religious and magical attributes
Toadflax can invade healthy native vegetation and thereby alter the species
composition of natural and desirable plant communities. Easily out-competes Sage –
often used for smudging and cleansing ceremonies as well as for treatment of colds.
COMMON TANSY (Tanacetum vulgare)
Identification:
• ID KEY: Common tansy is often confused with tansy ragwort, common tansy has
no ray flowers whereas tansy ragwort does
• Aromatic perennial growing to 0.4 to 1.5 m in height
• Upright stems are often purplish red and dotted with glands
• Deeply divided dark green leaves; almost fern-like in appearance
• Yellow "disc" flowers in cluster at top of plant; no ray flowers
Habitat: Common tansy grows at low to mid-elevations along roadsides, stream banks,
in disturbed habitats, and pastures; it grows best in full sun and in fertile, well-drained
soil.
Origin: Europe/Asia
Distribution: Common tansy is found in the following regions: Bulkley-Nechako, Central
Kootenay, Columbia-Shuswap, East Kootenay, and North Okanagan Regional Districts,
and within Greater Vancouver, Fraser Valley, southeast coast of Vancouver Island, Gulf
Islands, Sunshine Coast, and Squamish/Pemberton. It is considered a major concern in
the Kootenay, Okanagan, and Omineca regions.
Other: Undesirable forage and may be toxic to livestock, it can be toxic to humans if
large quantities are consumed
5 Spread: By seed and roots. Seed can be transported on animals, clothing and vehicles.
Seeds can remain viable for up to 25 years; therefore, stopping seed spread is a main
concern.
Impacts/Uses: May have been traditionally used as an insecticide or insect repellent.
FIELD SCABIOUS (Knautia arvense)
Identification:
• ID KEY: large violet to pink, clover-like flowers at the ends of long leafless stalks
• Perennial
• Stems are upright and hairy with coarsely toothed, feather-shaped leaves
• Well developed, woody taproot
Habitat: Found on roadsides, pastures, and fields at mid-elevations.
Origin: Europe – escaped ornamental
Distribution: Present the Cariboo and Peace agricultural regions and is most
troublesome in the Kootenays, Okanagan, Thompson, and Omineca regions.
Other It is sometimes planted as an ornamental and to attract butterflies.
Spread: Each plant can produce up to 2000 seeds that mostly fall near the parent plant
but seeds can also be spread by birds and human activities. The seeds remain viable in
the soil for many years.
Impacts/Uses: It competes with forage stands and native pastures and is capable of
invading undisturbed plant communities. Once established, it is difficult to eradicate.
GIANT HOGWEED (Heracleum mantegazzianum)
Identification:
• ID KEY: Perennial member of the Parsley or Carrot family, resembles our native
plant, cow parsnip, grows up to 6 m or more
• Stem is stout, dark reddish in colour, 5-10 cm in diameter
• Leaf stalks are spotted and produce a compound leaf that can expand to 1.5 m
across, each leaflet is deeply grooved or divided
• Stems and stalks are hollow and produce coarse hairs around a blister like
pustule
• Tuberous root-stalks form long-lived buds
• Small white flowers form together to make an umbrella shaped inflorescence compound umble
• The flower head can grow to 1 m in diameter
Habitat: Giant hogweed will grow in a variety of habitats but is most frequently found
adjacent to streams, creeks, roads, in vacant lots or in rights of ways. It is frequently
found in areas that are considered moist to wet.
Origin: Asia – escaped ornamental
Distribution: In BC it is known from southern Vancouver Island, the Gulf Islands, and
Vancouver.
6 Other: A plant takes several years from the time it germinates until it develops a
flowering stem. After flowering it sets seed and dies. Additional crowns may form on
individual plants that continue to flower and develop seed.
Spread: Giant Hogweed reproduces through seed and perennial buds. Viability of seed
can exceed more than seven years.
WARNING: The greatest concern from giant hogweed is human health. The blister like
pustules on stems and stalks exude a clear watery sap that sensitizes skin to ultraviolet
radiation. Affected areas are subject to severe burns that usually result in blistering and
painful dermatitis. Blisters often result in purplish to blackened scars.
Impacts/Uses: Giant Hogweed's tenacious and invasive nature allows it to readily
occupy and crowd out native vegetation. In riparian areas it forms a dense canopy,
out-competing native species and causing stream bank erosion.
LEAFY SPURGE (Euphorbia esula)
Identification:
• ID KEY: Inconspicuous greenish yellow flowers
• Perennial with creeping root system
• Grows to 0.7m tall
• Leaves spirally arranged up the stalk
Habitat: Leafy spurge grows in areas of full sunlight and dry soil but can tolerate a
variety of habitats, such as roadsides. It occurs in agricultural areas, natural forests,
range/grasslands, rural/disturbed, scrub/shrublands, urban areas.
Origin: Europe/Asia
Distribution: There are solated infestations of leafy spurge throughout southern and
central BC.
Other: Ranked as one of the 100 most invasive species in the world – World
Conservation Union.
Spread: Leafy spurge develops an extensive root system that can reach 4.5 m below
the soil surface and up to 10 m laterally. By midsummer, leafy spurge produces high
yields of pollen and seed, up to 3,400 pounds of seed per acre.
Impacts/Uses: The stems contain white milky latex, an irritant to skin and grazing
animals. An infestation of leafy spurge eliminates forage-worthy grasses while providing
no nutritional value. It out-competes native vegetation by consuming available water
and nutrients, sprouting new plants out of the existing root system, and by shading
sunlight and excreting toxins that inhibit growth of surrounding plants.
ORANGE HAWKWEED (Hieracium aurantiacum)
Identification:
• ID KEY: Flowering stalks are covered in stiff black hairs
• Fibrous rooted perennial with above ground runners
• Vibrant orange flowers (it is the only hawkweed species with orange flowers)
7 • Grows 30 to 60 cm tall
• Leaves mostly basal
• Flower stalks are leafless
Habitat: grows at low- to mid-elevations, usually in open areas such as pastures,
meadows, clearings, roadsides, and disturbed sites.
Origin: Europe
Distribution: Scattered and locally abundant in Central and Southern BC and has
isolated infestations on Vancouver Island. It is regarded as a major concern in the
Kootenay, Okanagan, Thompson, Cariboo, Omineca, and Peace River agricultural
regions.
Other: Seeds will mature after plant is cut or pulled so dispose of plants in the garbage.
There are 14 species of this plant in BC (both native and introduced).
Spread: Seeds are primarily spread by recreationalists.
Impacts/Uses: Orange hawkweed forms dense mats of rosettes that reduce natural
forage and threaten natural diversity.
OXEYE DAISY (Leucanthemum vulgare)
Identification:
• ID KEY: Oxeye daisy is often confused with the ornamental Shasta daisy, which
has larger yellow disk (2-3 cm) and white ray flowers (2-3 cm).
• Short-lived perennial
• Daisy-like flowers at the end of course, slender stems, with lower spoon-shaped
leaves
• Central yellow disks grow 1-2 cm wide and white ray flowers 1-2 cm long
• Can grow up to 1 m in height at maturity
Habitat: Occurs at low- to mid-elevations in grasslands and dry to moist forests. Due to
its unpleasant taste, most grazers avoid this plant, leaving it to spread easily within
grazed grasslands, pastures, and rangelands.
Origin: Europe/Asia
Distribution: Present in the Kootenays, Lower Mainland and Vancouver Island and is of
major concern in the Cariboo, Okanagan, Peace River, Thompson, and Omineca
regions.
Spread: Oxeye daisy reproduces by seed and underground stems. A single plant
produces 26,000 seeds and dispersal from parent plants lead to nearby infestations.
Impacts/Uses: Infestations decrease forage for wildlife, decrease local plant
biodiversity, and may compromise vegetative ground cover due to its growth form that
results in exposed soil.
8 BURDOCK (Arctium spp.)
Identification:
• ID KEY: Large, coarse biennial herb
• Purple flowers
• Velcro-like seed capsules
• large hairy basal leaves with wavy margins
• grows 0.5 to 3.0 m tall
Common burdock (Arctium minus) grows 1 to 3 metres in height; lower leaf stalks are
hollow; flower heads are less than 2.5 cm across and scattered along the stems
Great burdock, sometimes called giant burdock (Arctium lappa) is similar in
appearance but lower leaf stalks are solid and flower heads are over 2.5 cm across
and are arranged in a flat-topped cluster rather than along the stem
Habitat: Common burdock (Arctium minus L.) is found at low- to mid-elevations in
grasslands and forests. It can commonly be found growing along roadsides, ditches,
stream banks, pastures, and disturbed habitats. It often occurs in riparian areas that
have moist, fertile soils with high nitrogen contents.
Origin: Europe/Asia
Distribution: Established throughout much of Canada and the US. It is frequent in
coastal, west-central, and southern BC from low- to mid-elevations. Burdock is a major
concern in the Okanagan, Thompson, Cariboo, Omineca, and Peace regions, and is
present in the Kootenay, Mainland, and Vancouver Island regions. Great burdock
(Arctium lappa) is rare in southern BC.
Other: Because of its diuretic effects, common burdock has been listed as a poisonous
plant.
Spread: Bur-like seed heads are readily dispersed by attaching to animal fur or clothing.
Common Burdock typically produces 6,000–16,000 seeds/plant.
Impacts/Uses: The Secwepemc used the roots as a blood purifier.
ST. JOHN’S WORT (Hypericum perforatum)
Identification:
• ID KEY: two-sided, rust-red stems and numerous clusters of bright yellow flowers
with five distinctly separate petals.
• Perennial forb
• Oblong leaves have prominent veins and are covered with dots and are
transparent when the leaves are held up to the light
• Mature plants grow to 1 m in height and turn a rusty red
Habitat: St. John’s wort grows at low to mid elevations in coastal, grassland, and open
forested regions. It is commonly found on rangeland, pasture, and meadows and along
roadsides and disturbed areas. It is best adapted to dry, gravelly, or sandy soils.
Origin: Europe/Asia
9 Distribution: Occurs in scattered pockets in the Kootenays, Okanagan, Boundary, North
Thompson, Cariboo, Skeena, Fraser Valley, and Vancouver Island areas. It is not present
in the Peace River area. It is common throughout the US Pacific Northwest.
Other: St. John’s wort contains a toxin that causes grazing animals to become sensitive
to sunlight resulting in intense skin irritation.
Spread: It is spread by seed and vegetatively from roots. The root system spreads
laterally and is capable of forming new buds that separate from the parent. It is
capable of producing 15,000–30,000 seeds/plant.
Impacts/Uses: St. John’s wort invades grazed and disturbed lands. In dense stands, it
displaces native plant species and reduces livestock and wildlife forage.
NODDING THISTLE OR MUSK THISTLE (Carduus nutans)
Identification:
• ID KEY: large, deep reddish-purple flower with a bract like a collar of spinetipped points
• Stems are spiny and winged except below the flower head
• Leaves are deeply lobed and spiny margined
• Biennial taprooted thistle
• On maturity the large purple flowers droop or "nod"
• Flowerhead bracts end in a strong, sharp spiny tip
• Mature plants can grow to 2.5 m tall
Similar species: similar in appearance to plumeless thistle (Carduus acanthoides)
Habitat: found along dry roadsides and disturbed habitats at mid-elevations; will invade
pastures, rangeland, forestland, cropland, and disturbed areas. It does not appear to
have any specific climatic requirements, other than a cool period before flowering.
Origin: Europe/Asia or North Africa
Distribution: Found throughout North America. Nodding thistle occurs in isolated pockets
in the Chilcotin, Thompson, Nicola, Kootenay, Okanagan, Similkameen, Boundary, and
Bulkley Valley areas of BC.
Spread: A single plant produces 10,000 seeds but has been known to produce 100,000.
Seeds are dispersed by wind, water, wildlife, and livestock. Seeds can remain viable for
at least 10 years.
Impacts/Uses: A highly competitive weed that invades pasture, rangeland, forestland,
cropland, and disturbed areas, where it spreads rapidly and forms extensive stands.
Nodding thistle may produce allelopathic chemicals that inhibit desirable plants
beyond the spread of the rosettes.
10 ALERT SPECIES
~Please include two of these species in your presentation.~
BLACK HENBANE (Hyoscyamus niger) - ALERT SPECIES
Identification:
• ID KEY: Has tubular, showy greenish-yellow flowers that are about 5 cm across
with deep purple veins and centers
• Entire plant is covered with greasy hairs
• Member of the nightshade family
• Reaches heights of up to 1 m
• Similar species: Black nightshade (Solanum americanum) is smooth (not covered
in hairs). Hairy nightshade (Solanum physalifolium) has much smaller, white
flowers.
Habitat: Pastures, fence rows, roadsides, and waste areas
Origin: Mediterranean
Distribution: Mid- and Eastern Canada and Northern US.
Other:
WARNING: All plant parts of black henbane are considered highly toxic and can be
fatal if eaten. It is poisonous to all livestock and humans, even at low doses. Symptoms
of poisoning include: Salivation, headache, nausea, vomiting, diarrhea, rapid pulse,
convulsions, and coma.
It can cause skin irritation if it is touched with bare skin.
Spread: Fruit has a thickened lid that pops off at maturity, spilling the black seeds
(10,000-500,000 per plant)
YELLOW STARTHISTLE (Centaurea solstitialis) - ALERT SPECIES
Identification:
• ID Key: Bright dandelion-like flowers with sharp spines surrounding the base
• Vigorous taproot
• Grows up to 1 m tall
• Stems and leaves are covered with a loose cottony wool that gives them a
whitish appearance
Habitat: Best adapted to open grasslands with an annual precipitation range of 25 to
150cm per year
Origin: Europe and Asia
Distribution: Not currently known in BC. Found throughout US and southern Canada
Other:
From a survey of ranchers in California the estimated cost of yellow star thistle to forage
losses was $7.65 million with out-of-pocket expenditures to ranchers of was $9.45 million
a year. These losses make up 6-7% of the total annual harvested value (Eagle et al.
11 2007). In 1994 yellow star thistle was estimated to be spreading at a rate of 6,070 to
20,234 ha per year (Sheley and Larson 1994)
Spread: Spreads by seeds which can lie dormant for as long as 10 years
COMMON CRUPINA (Crupina vulgaris) - ALERT SPECIES
Identification:
• ID KEY: Can be distinguished by the fleshy seed leaves that have a bright purple
mid-vein
• Grows up to 1.2 m tall and forms 1 to 40 purple flowerheads on each plant
• Begins as a basal rosette and leaves become more divided and lacelike up the
stem
• Seedlings are similar to knapweed
Habitat: Invades hayfields, grass fields, grasslands and open forest sites.
Origin: Eurasia
Distribution: A few locations in BC on Vancouver Island and Cortes Island. Known in
Washington, Oregon, Idaho and California
Other: Decreases forage productivity and livestock carrying capacity
Spread: Spreads by seed
Control:
Mechanical – Hand pulling or hoeing can be effective for small infestations
Fire – Prescribed burning has reduced seedling populations but long term effects are
not known
Herbicides – Several herbicides including clopyralid, 2, 4-D, dicamba and picloram
have been effective
BUFFALOBUR (Solanum rostratum) - ALERT SPECIES
Identification:
• ID KEY: Low growing yellow, spined, hairy annual plant
• The stems mostly branching in the upper part are erect and bushy, up to 60 cm
long
• The entire plant, except the petals, is covered by straight yellow spines, 1/8 to 1/2
inch long
• Extremely prickly, alternate leaves and prickly, bushy stem
• 5-lobed wheel-shaped yellow flowers
Habitat: Buffalobur is found in fields, overgrazed pastures, yards, roadsides, waste areas,
barn yards, will grow in sandy soils, as well as dry hard soils to rich moist soils of cultivated
fields.
Origin: Midwestern US
Distribution: Found throughout North America. Not known in BC.
Other: Considered a nuisance because burs get caught on animal fur and sheep wool
Spread: By seed
12 Control:
Mechanical - Prevention of seed production is possible with repeated, close mowing or
hoeing out plants before flower blossoms appear
Chemical – 2,4 D and Banvel is effective
GARLIC MUSTARD (Alliaria petiolata) - ALERT SPECIES
Identification:
• ID KEY: Each plant usually produces on flowering stem with small, white 4-petaled
flowers clustered at the end of the stem
• The root usually has a distinct “S” or “L” shape just below the stem
• In early spring, the roots and new leaves smell like garlic
• Mature leaves are triangular and become smaller towards the top of the plant;
basal rosette leaves are kidney-shaped
Habitat: Can grow in dense shade or sunny sites, including under forest canopy
Origin: Europe
Distribution: Victoria
Other: Produces chemicals that inhibit the growth of other plants, fungi and butterflies
Spread: Seeds can last in the soil for 10 years. It displaces native plants with its
aggressive mat-like growth pattern
MEADOW CLARY (Salvia pratensis) - ALERT SPECIES
Identification:
• ID KEY: Violet-blue flowers irregularly spaced down the stem
• Leaves are mostly basal and the long stem grows up to 60 cm tall
• The plant is aromatic, and covered with small hairs
Similar species: Clary sage, (S. sclarea) which is also invasive so report that too!
Habitat: Quite competitive on dry sunny sites and able to live on deeper, less well
drained sites as well
Origin: Eastern Europe and Morocco
Distribution: Not known in BC but occurs in Washington, Idaho and Montana (as well as
other US States).
Other: Meadow clary poses a threat to forage production and plant biodiversity by
displacing less competitive, more desirable species. Classified as “Near Threatened” in
the United Kingdom
Spread: Spreads mainly from seed but can also re-grow from the persistent taproots.
Introduced as a garden ornamental
PERENNIAL PEPPERWEED (Lepidium latifolium) - ALERT SPECIES
13 Identification:
• ID KEY: Dense clusters of white flowers near the ends of the branches
• Leaves are alternate, lance-shaped, and do not have clasping bases
• Leaves and stem are waxy
• Similar to hoary cress (Cardia draba) but those leaves have clasping bases
Habitat: Invades irrigated pastures, cropland and native meadows. Also infests
wetlands, riparian areas and other water courses
Origin: Eurasia
Distribution: In western North America and parts of the east. In BC, known in Vancouver,
the Thompson- Nicola and East Kootenay
Other: It can tolerate a wide range of soil water potential and survive up to 50 days in
submerged soil
Spread: Spreads by seed and vegetatively from roots
Control:
Mechanical – periodic mowing and spring burning can reduce density. Cutting and
pulling before seed set can be effective
Chemical – several herbicides are effective including Mesulfuron-methyl (US), dicamba,
glyphosate, chlorsulfuron, imazapyr, and a combination of glyphosate and 2,4D
PUNCTUREVINE (Tribulus terrestris) - ALERT SPECIES
Identification:
• ID KEY: Its most distinguishing feature is the seedpod, which consists of five
sections that break into tack-like structures with stiff, sharp spines that easily
puncture bicycle tires
• It is an annual that branches from the base and spreads along the ground to
form dense mats
• The stems, which spread up to 3 m in length, are covered by hairy leaves that
are divided into 6 to 8 leaflets
• Produces tiny, yellow flowers in late summer
Habitat: Commonly found in dry sites like road shoulders, vacant lots, beaches and
unpaved parking sites
Origin: Mediterranean
Distribution: South Okanagan and one site near Enderby
Other: A problem for recreation and it punctures tires, including mountain bikes
Spread: Spreads by sharp seeds that may remain dormant for 4 to 5 years. These tiny
burs attach to animals, humans, or the tires of vehicles
Control:
Mechanical – Can be controlled by digging, hand-pulling or tilling infestations before
flowering and seed production
Chemical – Picloram, dicamba, and glyphosate have been effective
14 TEASEL (Dipsacus fullonum) - ALERT SPECIES
Identification:
• ID KEY: Prickly stems reach 1.8 m tall and have spiny flower heads that are
covered with small, lavender to white flowers
• Leaves are opposite, lanceolate and up to 25 cm long
Habitat: Favors disturbed sites such as roadsides, ditches, waste places, riparian sites,
fields and pastures
Origin: Europe
Distribution: Small infestations on Vancouver & Saltspring Islands, Okanagan, and
Boundary-West Kootenay regions
Other: Introduced as a garden ornamental and used in dried flower arrangements
Spread: A single plant can produce 2,000 seeds
15