Weed of the Month
Learn about noxious weeds and steps you can take to manage or eradicate. Each month we will bring you a new profile and helpful resources.
March Weed Profile
Dames Rocket
Hesperis Matronalis
Dames Rocket is a List B biennial species and belongs to the mustard family (Brassicaceae).
It is an escaped ornamental that can be found in rangelands, pastures, gardens, forests, ditches, and rights-of-way. It can be found in many wildflower seed mixes. It is a prolific seeder and escapes ornamentation quickly. It may be mistaken for some species of phlox. Phlox have five petals, compared to the four that Dames Rocket sports. Dames Rocket was introduced around the same time as European settlement.
Plants grow up to a height of four feet tall and have white or purple, four-petaled flowers. Flowers are clustered on terminal stalks. Seed pods are narrow and up to 1½ inches long, as with all mustard species, these pods are called siliques. Leaves are alternate, lanceolate (lancelike), 2-4 inches long, and have toothed margins.
Dames Rocket can spread quickly and displaces many of our native plant species.
RESOURCES
Wisconsin Department of Natural Resources
Noxious Weeds of Colorado 14th Addition
Colorado Weed Management Association
PHOTO CREDITS
Jamie Jones
Alicia Doran
Jeffco Invasive Species Management
Items of Interest
Weed of the Month
2023
January Weed Profile – Common Mullein
February Weed Profile – Cypress Spurge
March Weed Profile – Dames Rocket
2022
January Weed Profile – Knotweed
February Weed Profile – Rush Skeletonweed
March Weed Profile – Black Henbane
April Weed Profile – Chinese clematis
May Weed Profile – Houndstongue
June Weed Profile – Milk Thistle
July Weed Profile – Oxeye Daisy
August Weed Profile – Spotted Knapweed
September Weed Profile – Perennial Pepperweed
October Weed Profile – Yellow Flag Iris
November Weed Profile – Common St. Johns Wart
December Weed Profile – Field Bindweed
2021
January Weed Profile – Dalmatian Toadflax
February Weed Profile – Common Mulllein
March Weed Profile – Mediterranean Sage
April Weed Profile – Saltcedar
May Weed Profile – Absinth Wormwood
June Weed Profile – Eurasian watermilfoil
July Weed Profile – Yellow starthistle
August Weed Profile – Hairy willowherb
September Weed Profile – Yellow toadflax
October Weed Profile – Chamomile
November Weed Profile – Diffuse knapweed
December Weed Profile – Poison hemlock
2020
January Weed Profile – Cheatgrass
February Weed Profile – Myrtle Spurge
March Weed Profile – Hoary Cress
April Weed Profile – Leafy Spurge
May Weed Profile – Scotch Thistle
June Weed Profile – Dyer’s Woad
July Weed Profile – Orange Hawkweed
August Weed Profile – Purple Loosestrife
September Weed Profile – Teasel
October Weed Profile – Canada Thistle
November Weed Profile – Russian Knapweed
December Weed Profile – Russian Olive
