Spreading wallflower

Description:

"...a species of wallflower known by several common names, including spreading wallflower, bushy wallflower, and treacle mustard. It is native to Eurasia but it is known in many other parts of the world as an introduced species and a common roadside weed. This is an annual herb growing up to about half a meter high. The leaves at the base of the stem are widely lance-shaped, bumpy or toothed along the edges, and up to 15 centimeters long. The leaves farther up the stem are shorter, narrower, and more shallowly lobed or unlobed. The top of the stem is occupied by a raceme inflorescence of many [four-petaled] yellow flowers. The fruit is a silique up to 10 centimeters long." from Wikipedia

Habitat:

Disturbed sites, common roadside weed

Notes:

Found in Lory State Park, southwest of Bellevue, Colorado