IDENTIFICATION OF MINNESOTA INVASIVE

7-7-14 Itasca Co
IDENTIFICATION OF MINNESOTA INVASIVE:
Garlic Mustard (Alliaria petiolata)
SEARCH LOCATIONS
Upland and floodplain woodlands, along trails and
roads, in yards; shade to sun; damp soils
SEARCH TIME
Early spring—late April to early June (flowering)
SEARCH IMAGE
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Mature plant up to 4 feet tall
White flower head at top of stem
Search image
IDENTIFICATION CHECKLIST
Seed pods
1. Heart– or triangle-shaped stem leaves with
pointed teeth
2. Flower with four petals
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1 2
4 3
4 petals
OTHER HELPFUL NOTES
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Search image
single
flower
Flower head
Leaves have a garlic odor when crushed
Long slender seed pods form soon after flowering. Many mustards form similar seed pods.
Stem leaves are similar to other woodland
plants—look for the white flowers or seed pods
First-year plants form basal rosettes. These basal
leaves also have several look-alikes (on page 2).
pointed
teeth
Stem leaf
LOOK-ALIKES with white flowers blooming early spring in wooded areas
Sweet coltsfoot
4 petals
Bittercress
Canada violet
4 petals
Rock cress
MN native
MN native
MN native
 Compound leaves
(with many leaflets)
 Lance-like leaves
 Many flower petals
 Lance-like leaves
MN native
 Five flower petals
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INFORMATION ON MINNESOTA INVASIVE:
Garlic Mustard (Alliaria petiolata)
MINNESOTA STATUS: Restricted noxious weed
Importation, sale, and transportation of garlic mustard propagating parts are prohibited in
the state except as allowed by Minnesota Statutes, Section 18.82.
IF YOU FIND GARLIC MUSTARD
1) Record its location (GPS coordinates, labeled dot on map, mile-marker or other landmark)
2) Record the date
3) Document the plant (electronic images or make pressed samples that include items on the “checklist”
4) Contact Sara Thompson ([email protected]; 327–7393), Julie Miedtke ([email protected];
327-7365) or Mary Blickenderfer ([email protected]; 218-244-7996)
METHOD OF REPRODUCTION (biennial—1st year basal rosette; 2nd year bloom, set seed, die)
 Seeds—100+ seed produced by each plant, will remain viable in soil for up to 5 years
VECTORS OF SPREAD
 Short-distance dispersal of seed by explosive release (6 feet)
 Long-distance dispersal of seed by humans, pets, wildlife, water, vehicles, logging equipment
STRATEGIES FOR RESTORING NATIVE PLANT COMMUNITY
(Contact your county agriculture inspector and Web resources for specific details)
1) Ongoing garlic mustard controls—pulling, cutting/mowing (to eliminate seed production), burning, chemical or combinations of these—are necessary until seedbank is exhausted
2) Replant and/or reseed area with native plants (Note: Garlic mustard roots exude chemicals that inhibit
germination of other plants)
RESOURCES
Center for Invasive Species and Ecosystem Health: http://www.invasive.org
MN Dept. of Agriculture: http://www.mda.state.mn.us/en/plants/badplants/noxiouslist/garlicmustard.aspx
MN Dept. of Transportation: http://www.dot.state.mn.us/roadsides/vegetation/pdf/noxiousweeds.pdf
UW Extension YouTube on garlic mustard identification: http://www.youtube.com/watch?v=6WEYOELdf_c
GARLIC MUSTARD
LOOK-ALIKES with kidney– or heart-shaped basal leaves in wooded areas
Violets
Buttercup
Creeping Charlie
Basal rosettes
wavy leaf
edge
MN natives
2-3”
Basal rosette leaf
 5-lobed; white, blue or
yellow flowers
MN native
 5-lobed, yellow
flowers
Eurasia– invasive
 Leaves less than
1.5 inches
 Purple flowers