Vectors of spread:
General: Oxeye Daisy is an upright perennial, up to 1m in height in dense clumps.
Flowers: Flowers are daisy-like, with white rays and yellow disks, up to 5cm across. Flowerheads are solitary at the end of branches.
Stem: Stems are multiple and unbranched, up to 1m tall. They are smooth, frequently grooved, and generally hairless.
Leaves: Leaves are alternate, and decreasing in size up the stem. Upper leaves have wavy to toothed edges; lower leaves are spoon-shaped.
Non-native ornamental lookalikes
Shasta Daisy (Leucanthemum x superbum): a harmless ornamental, it has a larger yellow disk and white ray flowers. Shasta daisies also grow 15-30cm taller than Oxeye Daisies.
English Daisy (Bellis perennis): has much rounder foliage, and the flower petals are often double. English Daisies are also generally more compact, and they don’t grow past 15-20cm tall.
Native Asters (Aster spp.) and Fleabanes (Erigeron spp.) resemble Oxeye Daisy but typically have undivided leaf margins without lobes or teeth. Seeds of Aster and Fleabanes also have a pappus while Oxeye Daisy seeds do not. (Erigeron acris picture should be on its way from Bryan Kelly-McArthur – see email) (Also contacted a photographer off E-flora for permission to use a photo of Asters alpinus)
Scentless Chamomile (Matricaria perforata) is another invasive plant in the Sea to Sky. Its foliage is much lacier and fern-like. You can learn more about Scentless Chamomile here.
Habitat and Origin
Oxeye Daisy was introduced from Europe in the early 1800’s primarily as a grass seed contaminant, and subsequently spread as an ornamental.
It lives in mesic to dry areas such as roadsides, pastures, waste areas, grasslands, and forested areas within low to mid-elevations. In BC, it is common south of the 56th parallel.
Propagation and Vectors of Spread
Oxeye Daisy is spread by seed, garden waste, machinerie, footwear and soil; it is also sold as an ornamental. It also spreads vegetatively through underground stems.
One plant can produce up to 26,000 seeds, and seeds can remain viable in the soil for many years.
Economic and Ecological Impacts
Impacts of Oxeye Daisy infestations to the forest industry are not well-known and require further research; in terms of economic impact for agriculture, it carries several crop diseases including Yellow dwarf virus of potatoes.
Oxeye Daisy forms dense stands that inhibit forage production, dominating rangelands; it also reduces forage for wildlife and livestock, and decreases local plant biodiversity.
What Can I Do?
What to do if you spot it: You can report any Oxeye Daisy sighting by clicking here.
Oxeye Daisy is found throughout the Sea to Sky region, so STRATEGIC CONTROL is key:
- Regularly monitor properties for weed infestations.
- Ensure soil and gravel is free of Oxeye Daisy before transport.
- Don’t 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.
- Minimize disturbances that cause exposed soil (e.g., use grazing plans that prevent soil exposure from overgrazing), and use seed mixes with dense, early colonization (e.g., alfalfa or barley) to re-vegetate soils and resists invasion.
- Ensure plants (particularly flowering heads or root fragments) are bagged or covered to prevent spread during transport to designated disposal sites (e.g., landfill).
- Avoid wildflower mixes that contain Oxeye Daisy.
- Mechanical control: Hand dig before seed production, ensuring as much root as possible is removed. Mowing can be effective to reduce seed production, but should be repeated as it may stimulate vegetation growth. Grazing by sheep and goats may reduce Oxeye Daisy populations.
- Chemical control: Herbicide recommendations and use must consider site characteristics and be prescribed based on site goals and objectives. If recommended, any herbicide application must be applied through a certified pesticide applicator.
- Biological control: No biocontrol agent is currently available for Oxeye Daisy in BC. Further research is required.
- Invasive Species Council of BC, Oxeye Daisy TIPS Factsheet, https://bcinvasives.ca/resources/tips/oxeye-daisy
- E-Flora BC, Oxeye Daisy Atlas Page, http://linnet.geog.ubc.ca/Atlas/Atlas.aspx?sciname=Leucanthemum%20vulgare
- Invasive Species Council of Manitoba, Oxeye Daisy Species Profile Page, https://invasivespeciesmanitoba.com/site/index.php?page=oxeye-daisy