Draba verna is a small annual plant usually found
on sunny sites of low productivity. Most plants flower very
early in the growing season to take advantage of the spring
moisture on sites that will become very dry later in the
summer (the Latin epithet "verna" refers to Spring).
A smaller number of plants can be found later in the season,
depending on soil moisture.
They are commonly overlooked, even when in full flower,
because of their very small size. The plants are reported
to reach heights up to about 30 cm (1 foot), but most of
the plants that I have seen in Wisconsin have been less
than 8 cm tall, with some flowering at a height of only
2 or 3 cm. All the leaves are at the base of the plant,
arranged radially in a pattern commonly known as a "basal
rosette". There are no leaves on the flowering
stem. The four white flower petals are deeply lobed at the
tip and may give the impression of eight petals if hastily
judged. Petals are about 1.5-2.5 mm long.
Draba verna is undoubtedly more common in Wisconsin
than is indicated by the distribution map. Because it is
so small and it flowers so early it is probably frequently
overlooked. There are recent records from Brown, Door and
Marinette Counties that have not yet been added to the list
of vouchers upon which the distribution maps are based.
Based on 5 years of phenology data from Brown County the
average date of first flower is 4/16, with the earliest