(White campion, evening lychnis)
What does it look like?
White cockle (Lychnis alba P. Mill.) is an annual, biennial or short-lived perennial that reproduces by seed.
Flowers are white, showy and fragrant and open in late afternoon or evening and close in the morning. The flowers have 5 notched petals with an obvious tubed calyx with 10 – 20 prominent veins that surrounds the flower. Male and female flowers are found on different plants. Leaves are opposite, oblong with smooth margins and pointed at the tips. The plant is hairy, including both sides of the leaves, the calyx, and stems and plant height can be up to 1 metre.
This plant is most often confused with night-flowering catchfly, the main difference being that night-flowering catchfly is very sticky to the touch, and has male and female flowers on the same plant. Bladder campion is also similar, but is not hairy, and cow cockle is easily distinguished as it has pink flowers.
Its weedy nature…
White cockle is a non-native plant of Eurasian origin. Each female plant is capable of producing over 24,000 seeds! So the key to this weed’s success is that it is an extremely heavy seed producer.
It is a serious weed in cultivated crops and pastures and competes well for nutrients, moisture and sunlight. The seeds of white cockle are similar in size to clover, and are often a contaminant of forage seed as they are difficult to separate. Light and cool temperatures are also necessary for seed germination.
White cockle is also found on roadsides and in waste areas.
The main strategy in managing this weed must focus on prevention of seed production. Seed banks in the soil are usually exhausted over a 3 year period, providing no new seed is introduced to the area.
Cultural control can include mowing, cultivating, pulling or burning. In the case of cultivation it must be deep enough to cut the roots off below the crown. The plants need to be turned up in order that they dry out, and this is best done during low moisture and high temperature conditions. If temperatures are cool and soil moisture high – cultivation may simply result in transplanting existing weeds.
Be sure to use clean seed if seeding to forage or hay crops, as the clover sized seeds of white cockle are a common impurity. It is important to request the seed certificate when purchasing pedigreed seed.
Suppression of white cockle in cereal crops can include the use of Dyvel DS or Target when the weeds are at the 2-4 leaf stage. Roundup and Liberty can be used in herbicide tolerant crops. In legume crops, Embutox E (2, 4-DB) can be used for white cockle suppression, however some foliar resistance may occur. In non-crop areas where there are small patches of this weed, Dyvel DS or Escort will likely be effective as a spot treatment. Keep in mind that spot treatments in forage and hay crops will take out alfalfa and clovers.
Always follow any grazing or cropping restrictions and instructions on the label.
Transportation and Agriculture Services
Photographic credits to Alberta Agriculture, Food and Rural Development, the British Columbia, Ministry of Agriculture, Food and Fisheries, Field Guide to Noxious and Other Selected Weeds of British Columbia and Strathcona County, Transportation and Agriculture Services.