Draba verna Linnaeus
spring whitlow-grass
Family: Brassicaceae

basal rosette

Flowers of Draba verna have 4 small white petals and 4 pale green or yellow-green sepals. The petals are deeply lobed at the tip and if careful observations are not made it may appear that there are 8 petals. All leaves are at the base of the stem in a "rosette". Leaves are simple and unlobed with spreading hairs and they are usually less than 2.5 cm long. Several flowering stems may arise from each rosette. Plants are report4ed to reach 30 cm tall, but most in our area are much smaller All the plants I have seen in northeastern Wisconsin are less than 10 cm tall, and some are not more than 5 cm tall at flowering time.

Draba verna is a small, annual, alien plant that grows on dry, sunny sites of low productivity. It begins to flower very early, in early- to mid-April, and is usually done flowering by early May, after which time it is much harder to see. It appears to be an ephemeral species taking advantage of the spring moisture on sites that become intolerably dry later in the season.

The distribution of Draba verna shown on the map greatly underestimates its presence in Wisconsin. It is very small and flowers very early so it is often overlooked by collectors. It is certainly present in Brown, Door, Oconto and Marinette Counties in addition to those shown on the map and is relatively common in the appropriate habitat and season. It may be expected in sites where Veronica verna, Androsace occidentalis and other small vernal species are found, or with Veronica arvensis which has become extremely widespread and common in northeastern Wisconsin in the last 20 years.

Some botany books have called this species Erophila verna (L.) Besser. Despite the common name, this plant is not a grass.


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