Common Name: ox-eye daisy
Scientific Name: Leucanthemum vulgare
Code: LEVU
Group: Dicot
Family: Asteraceae
Growth Habit: Forb/herb
Duration: Perennial

What does it look like?

Ox-eye daisy is a prostrate herb with lateral sprouting stems that extend from a creeping rootstock. When in flower, the plant’s height generally ranges from one to three feet and the flowers consist of white petals with yellow centers. Leaves are one to two inches long, smooth, pinnately lobed or toothed and dark green on both sides (Bossard et al. 2000).

The flowering period generally ranges from May until August, typically mid-June in coastal areas. Ox-eye daisy generally reproduces in the first summer after it becomes established. It spreads by seed production and rooting underground stems. Seeds may remain viable in the soil for twenty years and even after passing through digestive tracts of animals. Prolonged periods of darkness and pre-existing dense groundcover can prevent ox-eye daisy seeds from germinating (Bossard et al. 2000).

Where does it grow?

This daisy is native to Europe. It exists from central California to Oregon and is used as an ornamental and often sold commercially in wildflower seed packets. Ox-eye daisy lives on sea bluffs, in canyons, and “alpine” mountain meadows. It prefers disturbed areas such as roadsides, fields, pastures, and former homesteads, and will readily spread to wildlands. Due to its ability to tolerate a variety of soil conditions, ox-eye daisy can thrive in a variety of plant communities including prairie, scrub, wet meadows, riparian forests, and open-canopy forests (Bossard et al. 2000).

Is it in our watershed?

Ox-eye daisy has not been documented in the Mattole at this time.

Why is it a problem?

This invasive daisy takes over plant communities, crowding out native species with its extremely dense growth. Ox-eye daisy is difficult to eradicate due to productive seedbank, long viability, and quick ability to resprout if not removed completely (Bossard et al.2000).

How do you get rid of it?

NOTE: Due to the viability of ox-eye daisy seed, it is critical to develop a containment strategy prior to creating a control strategy. One must consider environmental variables and the type of plant community. It is also helpful to identify the primary source of infestation. Small populations of oxeye daisy should be considered high priority treatment sites. Be sure to flag small sites so that it is easily visible for post-removal monitoring.

Complete eradification of large, well-established populations is very difficult, due to the small flower size and profuse seed production. Oxe-eye daisy seeds have an amazing ability to set and resprout, and it is critical to time the treatment and be persistent in the follow-up. However, prolonged periods of darkness and pre-existing dense groundcover can prevent oxe-eye daisy seeds from germinating (Bossard, 2000).

Manual/Mechanical Control: Hand removal can be efficient with smaller or widely scattered infestations, generally less than 1/4 of an acre. One method involves chipping around the base of the plant with a small hand pick, which loosens the plant making it possible to lift the entire plant out of the ground, rhizomes and all. If any stem pieces are left behind, an entire plant can resprout. A round-point shovel can be used for scooping out entire plants while a garden spade can be used to scrape plants out of more compacted soils (Bossard, 2000).

Mulching: Mulching has proven to be the most successful (non-chemical) method for removing large infestations of ox-eye daisy. Applications of certified weed-free rice straw has successfully eliminated masses of plants, both mature and immature. One bale of straw can cover about 100 square feet and should be applied in fall, at the beginning of growing season. Monitoring should happen early in the spring. Examine for remaining live plants. Mulch any new growth with a thick layer of straw before May.

If the infested area is populated with numerous woody or brushy plants, it may be necessary to conduct substantial lopping or brush removal prior to laying down a thick layer of mulch (Bossard, 2000).

Grazing: Intensive cattle grazing can control ox-eye daisy. In a continuous grazing system, under high stocking rates, cattle will eat this species despite its high acidity (Bossard, 2000).

Author:
Unity Peterson, Invasive Plant Program Coordinator, Mattole Restoration Council, Petrolia, CA.

Photograph:
Nick Kurzenko, 2001

References:
Bossard, CC., J.M. Randall and M. Hoshovsky. (eds.) 2000. Invasive Plants of California’s Wildlands. University of California Press, Berkeley, CA. Online version: http://groups.ucanr.org/ceppc/Invasive_Plants_of_California's_Wildlands/