Descurainia sophia (Flixweed)
Image credit: Pretty DrugthingsIdentification tips
Tip #1: The name of the genus, "Descurainia", honors François Descourain (1658-1740), a French botanist and doctor/pharmacist. The name of the species, "sophia", is from the Greek word meaning "wisdom", both this homage and the name of the species is due to the various uses of this plant for medicinal use.
Plant shape
2º Identification tip: it has its initial development in rosette, presenting stems that protrude from the rosette.
Leaves
3º Identification tip: the leaves are alternated and formed by foliolos, are covered by hair, that can be numerous (depends on the environment and genotype) and the hairs can also be simple or branched. The older the leaves the more divisions they have, while the younger ones are less laced. The leaves somewhat resemble the leaves of common ragweed.
Stem
4º Identification tip: the stems are upright, green to purple, have hairs. Plants are usually very branched, but may not be branched.
Flowers
5º Identification tip: the flowers have 4 yellow petals and 4 linear and greenish yellow oblong sepals, both have no hair or are sparsely covered with hair. The flowers are grouped into flat bunches.
Seeds
6º Identification tip: the seeds are small orange to brown collaring, a good tip is that they get sticky when wet.
Pod
7º Identification tip: the pods are thin and can be slightly curved (half moon), they are formed from the bottom up. Inside the pod, there is a single row of 12 to 25 seeds, with barely visible constrictions between the seeds.
Seedlings - the terror of all
8º Identification tip: the cotyledon is spear-shaped and hairless, the first pair of true leaves is opposite (the next pairs will be alternated), both the first pair of leaves and the stem of the seedling is covered by branched hairs.
Extra references:
http://ipm.ucanr.edu/PMG/WEEDS/flixweed.htmlhttp://ipm.ucanr.edu/PMG/WEEDS/flixweed.html