CRUCIFERAE MUSTARD FAMILY 
ROCK CRESS 
Arabis lyrata L. 
The Rock Cress grows in rocky and sandy places. It is 
likely to be found, therefore, in any of those places in the state 
where there are rock outcrops or sandy soil. It is widely dis- 
tributed, being found in suitable situ- 
ations from Ontario to Connecticut, "> 
Virginia and Tennessee, southwest to £ (2 
Missouri and northwestward through 
Manitoba and British Columbia to ¥Y 
Alaska. It is also found in Japan. \ yl 
The plant has a fleshy taproot that XY ) 
lives through at least one winter, as in \ 
the more northern parts of its range it is 
biennial, and perennial farther south. 
The solitary or several stems grow 4-12 
inches high and usually are somewhat 
hairy toward the base but occasionally 
entirely smooth. There is a cluster of 
basal leaves, often several times the 
number shown, which may be hairy or 
smooth. 
The number of flowers on each stem 
varies greatly. The 4 yellowish green 
sepals are small but the pure white 
petals are longer and quite conspicuous. 
There are the usual 6 stamens, 2 
shorter than the others, and 1 pistil 
with a short slender style. The fruit 
is a pod containing 2 rows of seeds. 
The Sicklepod, Arabis canadensis L., is a perennial 2-4 feet high, 
mostly unbranched, with numerous lanceolate leaves barely toothed 
or entire and sessile or nearly so. The small greenish white flowers 
are in terminal or lateral racemes. They are followed by flat green 
pods 2%-4 inches long and curved, which remain after the leaves 
have fallen and then open from below by the 2 elastic valves. 
The Bank or Smooth Rock Cress, Arabis laevigata (Muhl.) Poir., 
is abundant on steep, shaded, wooded bluffs throughout. It is 2-4 
feet tall, smooth and covered with a bloom. The lanceolate or linear 
stem leaves are mostly toothed and are attached by arrow-shaped 
clasping bases. The oblong-linear petals of the small greenish white 
flowers are scarcely longer than the calyx, and the long narrow pods 
are recurved-spreading on generally erect pedicels. 
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