Ox-eye daisy is a noxious weed that has been spotted throughout Alberta, especially in central and southwest areas of the province.
It commonly grows along roadsides, waterbodies, fields and pastures, forest openings, disturbed areas, and urban areas. This weed looks similar to scentless chamomile and is often not perceived as an invasive plant because it looks like a wildflower and is sometimes sold in wildflower mixes. Consumers need to fully read the contents of wildflower mixes so they can avoid the spread of invasive ornamentals. (There are no native white-flowered daisies in Alberta.)
Ox-eye daisy is a problem because it can grow in a wide variety of habitats and thrives in low-nutrient soil where other plants are unable to grow. It produces up to 26,000 seeds per plant and the seeds can remain viable in the soil for two to three years. The plant can also reproduce by short, shallow roots (rhizomes). Cattle avoid the plant and so as it spreads, the amount of forage available for grazing decreases. Dense infestations can increase the amount of bare soil in an area as it does not provide good ground cover.
The plant grows up to one metre tall and stems are usually smooth, sometimes branched near the top. The leaves decrease in size as they go up the stem; lower leaves have toothed margins; and upper ones narrow and alternately arranged.
Once this invasive ornamental starts to spread it can be very difficult to contain, so contact your local Agricultural Fieldman if you think you’ve spotted it. For more information on this or any invasive plant, contact your local Agricultural Fieldman or the Alberta Invasive Species Council.