Daisy, Oxeye

Ox-eye daisy produces up to 26,000 seeds/plant, which can remain viable in the soil for a minimum of 2 to 3 years.  Research has shown that 82% of seed remains viable after 6 years, while 10% remains viable after 39 years.  The seed is viable 10 days after flowering begins.

Spreads by seed and by short, shallow rhizomes. Often found as a contaminate in grass seed, manure and hay. Approximately 40% of the seed remains viable after being consumed by livestock. Spreads by seed and by short, shallow rhizomes. Often found as a contaminate in grass seed, manure and hay. Approximately 40% of the seed remains viable after being consumed by livestock.

Dense stands of ox-eye daisy can decrease plant diversity and increase the amount of bare soil in an area, as they do not provide good ground cover.  Ox-eye daisy is also a good competitor against crops, causing yield reductions and reduces carrying capacity in infested pastures.  Oxeye daisy is often confused with the ornamental Shasta daisy.  It has also been noted that there is the potential for oxeye daisy and Shasta daisy to hybridize making identification even more difficult.  Ox-eye daisy can taint the milk and meat of wildlife or livestock when grazed.  Oxeye daisy can also act as an alternate host for Aster yellow and several nematode species.

Integrated weed management (IWM) considers the overall management of a weed species with the objective of preventing the establishment of the weed from ever occurring, to prevent the spread or to minimize the impact.  IWM relies on the combination of a variety of methods such as chemical, biological, mechanical, and cultural controls as well as overall preventative measures.  Using IWM creates an opportunity to use herbicides more selectively, which reduces the impact on the environment as well as slow the development of weed resistance to herbicides.

Preventative – Minimize disturbance and seed dispersal, eliminate seed production and establish and maintain healthy competition.  Use only weed free grass seed, wild flower mixes and weed free hay.

Competition – Ox-eye daisy was out-competed by forages when fertilizer was spring-applied to hayland for two years.  Barley competes well with daisy, as it is a competitive crop.  New seeded alfalfa competed better with ox-eye daisy (only 12 ox-eye daisy/m2, 2 years after seeding) than other forages including orchardgrass, smooth brome, kentucky bluegrass, alsike clover, creeping red fescue, meadow brome, and timothy (34, 39, 51, 58, 67, 73 and 92 ox-eye daisy/m2 respectively) (Cole 2001).

Fertilization - Two years of 100 kg/ha of nitrogen significantly reduced ox-eye daisy plants into the following year.  Three years of fertilizer to soil test recommendations (P-K-S) and 100 kg/ha of nitrogen enhanced forage competition, which effectively removed nearly all ox-eye daisy from hay land (Cole 2001).

Cultivation - Tillage below the shallow rhizomes is an effective control method.

Mowing - Timely mowing can prevent seed production, however as it does not remove the rhizomes from which ox-eye daisy can regrow, and therefore success is limited.  Research indicates frequent mowing in one growing season actually increases ox-eye daisy populations two years after mowing.  It is thought that mowing removes canopy competition of surrounding plants, allowing ox-eye daisy to thrive (Cole 2001). 

Grazing – Generally unpalatable to livestock.  The presence of cattle may reduce populations of seedlings, rosettes and seed production, but not of mature stems as they avoid grazing them.  Reduction in the population is generally from trampling and stem removal (Olson et al. 1997).  If a pasture is continuously over-grazed by cattle, it greatly increased ox-eye daisy populations (Norman 1957).   Sheep or goats have been effective in selectively grazing ox-eye daisy.  Ox-eye daisy can taint the milk or meat of wildlife or livestock when grazed.

Biocontrol – None.  Oxeye daisy produces polyacetylenes and thiphenes which are generally toxic to insect herbivores.

Integrated weed management - Combining fertilization with herbicide treatment (or nearly any other treatment) seems to be the most effective way of controlling ox-eye daisy.