Hoary Cress Information

Hoary Cress-SeedlingHoary Cress-LeavesHoary Cress-Flowers

(Cardaria draba)

Hardy perennial with stout, erect or procumbent stems
Seedling leaves have a sharp pepper taste

Cardaria draba is distinguished from other Cardaria species by:
            *Heart-shaped fruit containing only 2 seeds
            *As fruit matures and dries, distinct veins appear

Cardaria draba is distinguished from Lepidium species by:
            *Lepidium leaves are perfoliate (completely encircle the stem)
            *Lepidium fruit is flattened, keeled or winged
            *Lepidium fruit is dehiscent, cardaria is indehiscent

            *Prefers non-shaded, moist, disturbed soils with little competition
            *Roadsides and ditches
            *Cropland and wasteland
            *Watercourses and irrigation canals

            *Blooms May through July
            *Flowers are four-petalled with long, narrow bases (spoon-shaped)

            *Two seed per fruit
            *Plants and produce up to 850 fruits per flowering stem
            *Germination rates of 93% are common
            *Temperature range for germination: 68-86 degrees
            *Dispersal by animals, humans and water

            *Roots grow 3-6 feet deep
            *25 day old plant: 10" taproot, 5-6 lateral roots
            *100 day old plant: 48 shoots, 80 root buds
            *1/2" root segment can regrow if within 2-4" of surface

Growth and reproduction:
            *Under ideal conditions, rosettes form 2-3 weeks after emergence, roots develop within 5 weeks
             and aboveground branching within 13 weeks
            *Lateral root growth can exceed 10 feet during the first year, 2-3 in the following seasons 
            *Reproduction from rootstocks and seeds

            *Mowing 2-3 ties per season after flowering, can weaken the plant
            *Repeated cultivation at 10 day intervals prior to seed set Herbicides: chlorsulfuron, metsulfuron,
             2, 4-D

            *Reduces crop yields and forage production, toxic to livestock
            *Displaces native species reducing biodiversity