Tag Archives: smooth rock cress

Smooth Rock Cress Boechera laevigata

Boechera laevigata Al-Shehbaz

April to June                                                 N                                 Family: Brassicaceae

smooth rock cress flowers

Flower: Flowers form a loose cluster on the stem tip with new flowers forming as the stem gets longer. The cluster hangs at an angle downward from the drooping end of the stem. Each flower is on a long stalk and has four white petals barely longer than the sepal cup surrounding them. The pistil starts elongating out through the petals as soon as the flower is fertilized.

smooth rock cress leaf

Leaf: The first year leaves are in a low growing rosette. They are long and narrow with a short petiole. They are gone by the time the stalk appears. Alternate stem leaves are at wide intervals. Each sessile leaf is long and narrow with a midvein. The end of the leaf has two long lobes surrounding the stem. Many leaves have teeth often toward the base but the entire edge can have teeth. The leaves are smooth with no hairs.

Smooth rock cress under leaf

Stem: The stem appears the second year. It can reach three feet tall and often droops over at the top. It is green, round and smooth with no hairs. It can turn reddish in full sun.

smooth rock cress stem

Root: The root is a biennial taproot.

smooth rock cress fruit

Fruit: The seed pod is long and curves out then hangs down. It is on a long stalk and has no hairs. Cut across the pod is round. Seeds form a single line inside the pod.

Habitat: This plant likes light shade preferring low to hilly deciduous woods growing in moister places.

Smooth Rock Cress

smooth rock cress plant

There are lots of cresses and rock cresses. Smooth Rock Cress is noticeable because of the tall drooping stem of flowers. It favors moister wooded areas with a bit of sun in the spring. I find it along the road near the river in the floodplain and on the hills on the uphill side of trees tucked near the tree.

The flower cluster looks like a falling pile of light green cups from the side. The flower petals are barely visible until you look at a flower head on. Then the four white petals are obvious.

Because there are many cresses, there are some characteristics setting Smooth Rock Cress apart. The plants are completely hairless giving them that smooth look. The seed pods have a single row of seeds visible as bulges along them, are round in cross section and, although they start out pointing up, spread out then droop down as much as three and a half inches. The leaves on the flowering stem are different too with their two long lobes, one on each side of the stem seeming, at times, to try to wrap themselves around the stem.

The plant is a biennial but the rosette of leaves from the first year goes unnoticed. It is the flowering stalk with its drooping spray of flowers that is seen by those who take the time to look.