Fernleaf Yarrow

Fernleaf Yarrow

Achillea filipendulina
IMG_6832-scaled

Status in Squamish:

NOACTION

Status in Whistler:

NOACTION

Status in Pemberton:

NOACTION
Vectors of Spread:
Synonyms
  • Soldier’s Woundwort
  • Nosebleed
  • Milfoil
  • Achillea eupatorium
  • Achillea filicifolia
  • Tanacetum angulatum
ID Characteristics

General: Fernleaf Yarrow is a flowering herbaceous plant in the Asteraceae (daisy) family.

Flowers: Are long-lasting, yellow and grow in large clusters. These large clusters are comprised of tiny rays and discs, and can measure up to 10 cm across.

Stems: Fernleaf Yarrow stems are erect, rising above the foliage to 90 – 150 cm tall.

Leaves: Are fern-like, aromatic (spicy) when crushed, and green. Fernleaf Yarrow leaves are generally  5 – 20 cm long, divided into as many as 15 pairs of linear-lanceolate toothed segments, and feathery. They grow fairly evenly in a spiral pattern along the stem.

Roots: Are shallow but fibrous and abundant, and they easily spread horizontally through the soil.

Similar Species

Non-Native:

Thayne Tuason, CC BY-SA 4.0 via Wikimedia Commons

Common Yarrow (Achillea millefolium) looks similar to Fernleaf Yarrow, but the latter is taller.

Report

Please report any sighting of Fernleaf Yarrow by clicking here.

Habitat and Origin

Fernleaf Yarrow is native to the Caucasus and Central Asia.

Fernleaf Yarrow is commonly found flourishing in waste areas, meadows, pastures as well as alongside railway tracks and roads. It thrives in full sun and can subsist in a variety of soil conditions, but prefers dry soil.

Current Distribution

Fernleaf Yarrow Distribution map 2021

Propagation & Vectors of Spread

Fernleaf Yarrow reproduces both by seed and vegetatively, through underground rhizomes.

Fernleaf Yarrow seeds are spread by humans and animals; root cuttings or fragments are also responsible for the plant’s vegetative spread. Lastly, since Fernleaf Yarrow is still sold in the horticultural trade, it is sometimes found in wildflower seed packs, sold in nurseries and planted by gardeners.

Ecological, Economic, & Health Impacts

Ecological: 

  • Outcompetes native plants
  • Reduces biodiversity

Economic:

  • Fernleaf Yarrow hosts powdery mildew, rust and stem rot, which can spread to farmers’ crops.
What Can I Do?

Fernleaf Yarrow is found throughout the Sea to Sky corridor, so PREVENTION of further spread is key:

Learn to identify Fernleaf Yarrow: use the images presented in this profile page to learn how to identify Fernleaf Yarrow

What to do if you spot it: You can report any Fernleaf Yarrow sighting by clicking here.

DO:

  • Regularly monitor properties for weed infestations.
  • Minimize soil disturbances and promptly revegetate disturbed areas to prevent the growth of Fernleaf Yarrow.
  • Check wildflower mixes to ensure that they do not contain Fernleaf Yarrow.
  • Ensure all flowering heads or buds are bagged or covered to prevent spread during transport to designated disposal sites.
  • Maintain a healthy, thriving native plant community to help prevent the spread of Fernleaf Yarrow to some extent.

DO NOT:

  • Unload, park or store equipment or vehicles in infested areas; remove plant material from any equipment, vehicles or clothing used in such areas and wash equipment and vehicles at designated cleaning sites before leaving infested areas.
  • Plant Fernleaf Yarrow in a garden, no matter how well-contained its enclosure may seem.
  • Compost any flowering heads or buds. Instead, dispose of Blueweed in the general/household waste stream at the landfill as the seeds will be able to persist the composting process.
  • Move soil, gravel, or fill that has been contaminated with Fernleaf Yarrow.

Control

Mechanical 

  • Digging and hoeing areas where Fernleaf Yarrow has spread can remove some of the rhizomes, but mechanical control is only effective if it goes down 30cm and removes every speck of Fernleaf Yarrow plant material (since the rhizomes can generate new plants).

Chemical

  • Dicamba, chlorsulfuron, clopyralid, MCPA, tricloplyr and 2,4-D are all reported to be effective in controlling Fernleaf Yarrow infestations.
  • We recommend that any herbicide application is carried out by a person holding a valid BC Pesticide Applicator Certificate. Before selecting and applying herbicides, you must review and follow herbicide labels and application rates; municipal, regional, provincial and federal laws and regulations; species-specific treatment recommendations, and site-specific goals and objectives.

Biological

There is no biocontrol available for this plant.

References