RMD-13-04: Consolidated Pest Risk Management Document for pest plants regulated by Canada
Executive Summary

Hardiness Zone 2
Canada: ON/B.C. (under official control)
Other: US, Mexico, Asia, Europe

• Agriculture: cereal crops (primarily winter wheat and also spring wheat) and pasture
• Environment: disturbed areas such as railways

• Losses in crop yield and quality in the U.S. estimated at $150 million annually.
• Field experiments demonstrated a first year infestation of 1 to 5 plants per square metre led to yield losses of 3 to 30% the following year.
• Presence of spikelets has been shown to lower wheat grade in the U.S. and cause dockage losses in winter wheat.
• Reduction in planting of winter wheat, a component of reduced-tillage systems.
• Potential for hybridization with herbicide tolerant wheat varieties if A. cylindrica is allowed to establish.

• Contaminated farm machinery
• Spillage of grain from trucks and rail cars
• Contaminated grain lots (particularly winter wheat), straw and livestock

Hardiness Zone 6
Canada: absent
Other: US, Africa, Asia, Europe, South America, Australia, New Zealand

• Agriculture: winter cereal crops and pasture
• Environment: moist meadows, deciduous forests and disturbed ground

• Most damaging weed of winter cereals in Europe.
• Difficult to eradicate from cultivated fields. Populations in England have developed resistance to several grass herbicides.

• Contaminated grass seed, cereal grains, hay, straw, and manure

Hardiness Zone 6
Canada: absent
Other: US, Europe, Asia

• Agriculture: range and pasture, hay
• Environment: roadsides
• Social: recreational areas

• Displaces valuable forage species in pastures and rangelands.
• Its sharp spines deter grazing animals, restricting access for livestock and reducing the value of hay.
• Infestations can impede recreational use and restrict access for wildlife.

• Contaminated clover seed
• Livestock
• Raw wool and raw hides

Hardiness Zone 5
Canada: absent
Other: US, Europe, Asia, South America

• Agriculture: horses, rangelands, cereals, orchards, vineyards, cultivated crops
• Environment: roadsides, wastelands
• Social: recreational areas, private land

• Toxic in large amounts to horses.
• Losses due to interference with livestock grazing and forage harvesting procedures.
• Lower yield and forage quality of rangelands. Livestock avoid grazing in heavily infested areas resulting in slower weight gain and reduced quality of milk, meat, wool and hides.
• Reduces wildlife habitat and forage, displaces native plants, decreases native plant and animal diversity, alters the water cycle (by using more water to a greater soil depth) and fragments habitat.
• Can limit access to recreational areas and reduce land value.

• Contaminated alfalfa seed, cereal grain, hay and nursery stock with soil
• Movement of vehicles, equipment and livestock

Hardiness Zone 4
Canada: absent
Other: US, Europe, Asia, Africa

• Agriculture: pastures, rangelands, hayfields, livestock
• Environment: undisturbed roadsides, waste places

• Could have serious economic impacts on forage and livestock production.
• Can be highly competitive and dominate sites, displacing other plant species and reducing biodiversity. It also increases the risk of soil erosion.

• Intentional import by tourists and recreational users
• Contaminated hay and seed
• Clothing on travellers
• Vehicles and equipment
• Livestock
• Wool

Hardiness Zone 5
Canada: absent
Other: US, China, Japan, Korea, Taiwan

• Environment: forests, scrub, herbaceous plant communities, mountain slopes, granite outcrops, along rivers, creek bottoms, roadsides, drainage canals, waste places, fence rows

• The large, edible tuber is flavourful and nutritious and is sometimes used in herbal medicine. Processed or dried roots can be imported rather than the plant being grown in Canada.
• The species is often planted for its ornamental value.
• Reduces native species richness and abundance and can cause branches of trees and shrubs to break.
• Manual and mechanical treatment methods are very time and labour-intensive; repeated herbicide treatments are necessary to kill underground tubers.

• Intentional introduction as an ornamental, medicinal plant or tuber crop

Hardiness Zone 5
Canada: SK
Other: US, South Africa, Russia, Uruguay, Argentina, Brazil, New Zealand, Saudi Arabia and United Arab Emirates.

• Agriculture: pastures, horses, sheep
• Environment: soil stability and productivity, threat to native species

• Pasture degradation, livestock and crop yield losses (e.g. cereals, hay and seed contamination and increased costs of control
• Ability to dominate pastures in its exotic range, toxicity to livestock and potential control issues due to herbicide resistance.
• May have a negative impact on the quality of Canadian honey.
• This species is a host of four plant pests

• Intentional introduction as an ornamental, industrial crop for commercial production,
• Fur of domestic animals
• Indigested seed
• Contaminated vehicles and equipment
• Contaminant of hay, soil, gravel or cereal and forage seed

Hardiness Zone 5
Canada: absent
Other: US, India, Nepal, China, Japan

• Agriculture: crop production areas, landscape plantings and turfgrass
• Environment: stream banks, moist woodlands, old fields and thickets, utility rights-of-way, roadsides, lawns, wetlands, ditches

• Once established, can crowd out native herbaceous vegetation in wetlands and forests within 3 to 5 years.
• Disrupts the quality of nesting habitats for birds
• Can alter natural soil conditions (e.g. higher pH), creating an inhospitable environment for many native species.
• Rapid growth leads to the creation of “mats” on the forest floor that negatively affects native woody species regeneration.

• Contaminant of bird seed, soil, nursery stock, and hay
• Packing material
• Fur of animals
• Human clothes and boots
• Vehicles

Hardiness Zone 7
Canada: absent
Other: South America, Australia, New Zealand

• Agriculture: pasture and range
• Environment: grasslands and lightly forested terrain

• The cost to control moderate to heavily infested land in New Zealand was estimated at $98.50 to $107.35 per hectare. Continued treatment must occur for up to 22 years before an economic benefit can be expected.
• Can out-compete native grasses, threatening the endangered Garry Oak Meadows ecosystem of south-western BC.
• Heavy infestations of conservation lands decrease their biological diversity and aesthetic value.
• Reduces carrying capacity of pastures due to its low nutritive value and poor palatability to livestock, but most pastures in Canada are outside of its potential range.

• Intentional import as an ornamental (seed and plants for planting)
• Contaminant of seeds of forage grasses, hay and raw wool
• Live woolly animals

Hardiness Zone 6
Canada: absent
Other: US, South America, southern Europe, tropical and southern Africa, Asia, Australia, New Zealand, Oceania

• Agriculture: potatoes, vegetables, pastures, orchards, vineyards
• Environment: heaths, shrubland, riparian habitats, freshwater wetlands, swamps, lawns, roadsides, disturbed and natural clay pans

• Considered a weed of 14 crops in 28 countries.
• Weed problem on lawns, golf courses and other turf areas where it is very difficult to control.
• Smothers low-growing plants and prevents recruitment of native woody species.

• Contaminant of turf grass seed, bird seed and grain
• Deliberate introduction as a forage plant

Hardiness Zone 6
Canada: absent
Other: US, Asia (most prominent in Japan, Korea and China), Türkiye, Caribbean

• Agriculture: nurseries, Christmas tree plantations, forage crops
• Environment: disturbed and riparian areas
• Social: parks and private land

• Coined “kudzu of the north”
• Affects production of trees and shrubs (nurseries) and Christmas tree plantations.
• Increased costs of control to the transportation industry, parks and recreation and home gardeners.
• Reduces native plant diversity, invades sensitive riparian areas and impoverishes food and habitat for native wildlife.
• Reduces the aesthetic value of properties and public areas. Its prickly vines are a nuisance to people and pets.

• Seed or plants associated with nursery stock
• Contaminated seed (e.g. Meliosma and Ilex)
• Contaminated hay or straw
• Vehicles and equipment

Hardiness Zone 6
Canada: absent
Other: southern Africa, Europe, Taiwan, Mexico, Argentina, Colombia

• Agriculture: range, pasture, vineyards, livestock, crops
• Environment: grasslands, stream margins, ruderal habitats, railway lines, roadsides, river ports, flat roofs, flower tubs, logging areas, storm-damaged forests, industrial sites, disused quarries, rocky sites, coastal dunes

• Capable of modifying landscapes and invading natural habitats such as dunes and cliffs.
• The plants are toxic to livestock and humans. The pyrrolizidine alkaloids have the potential to contaminate milk and honey products.
• Control and/or eradication in Europe are considered difficult and costly. Negative economic consequences associated with herbicide resistance have been reported from German railways to be 100,000 Euros per year.
• Its establishment could threaten Canada's ability to export commodities to the U.S. where it is a federal noxious weed.

• Contaminant of hay, grain, wool, ornamental plants and containers
• Association with livestock and people

Hardiness Zone 8
Canada: absent
Other: southern Africa, Madagascar, Réunion, Mauritius, Argentina, Colombia, Australia, Japan

• Agriculture: pastures, rangelands, cultivated land
• Environment: yards, fields, roadsides, disturbed land, coastal plains

• Strong competitor with desired pasture species, reducing pasture productivity.
• Toxic to poultry, pigs, cattle and horses.
• Costs due to herbicide use and toxic effects on cattle were estimated to be $11 million ten years ago in Australia (in non-drought years).
• Its introduction could threaten Canada's ability to export commodities to the U.S. where it is a federal noxious weed.
• Negative effects on biodiversity by competing with native vegetation such as grass and low-growing plants.
• Changes to the vegetation composition of an area could promote soil erosion.

• Contaminant of seed
• Association with travellers and their effects

Hardiness Zone 5
Canada: absent
Other: US, Mexico, South America, Australia, India, South Africa, Mediterranean basin

• Agriculture: cereals (wheat, sorghum, corn), soybeans, alfalfa, vegetables, grapes, some fruit trees, cultivated pastures, livestock corrals
• Environment: disturbed areas, roadsides, railways, riverbanks, canal-sides, construction sites, wastelands

• Considered one of the “worst weeds of the west.”
• Presence of the weed decreases yield and reduces quality and sale when found in harvested products.
• In Morocco, the value of infested fields reportedly decreased by 25%, while in the U.S. entire farms have been abandoned.
• The average total farm cost for this weed in the wheat belt of Victoria, New South Wales and South Australia was $1,730 (AUD) per year for control and $7,786 (AUD) per year in production losses.
• May replace native vegetation in overgrazed rangeland.
• Loss of value of agricultural land infested with the weed.

• Contaminant of forage and crop seed (corn), hay, straw and grain
• Livestock and manure
• Vehicles and agricultural machinery
• Nursery stock with soil
• Possible natural dispersal

Hardiness Zone 5
Canada: absent
Other: US, Asia, Europe, Australia

• Agriculture: rangeland
• Environment: roadsides, corrals, gravel pits

• Considered one of the “worst weeds of the west.”
• Can dominate native vegetation in dry habitats.
• Forms dense masses that displace beneficial species on rangelands.
• Control with herbicides is difficult due to its waxy leaf surfaces and extensive root system.
• Toxic to livestock, so infestations decrease available forage.

• Intentional import for planting (as plants for planting and seed)
• Contaminated alfalfa seed
• Vehicles