Corn speedwell (Rock speedwell, Wall speedwell)
Veronica arvensis

Description

A member of the plantain family, it is a hairy, erect to almost recumbent, annual herb, 9 to 40 cm high from a taproot. The leaves are oppositely arranged in pairs about the stem. The lower leaves have short petioles; the upper are sessile. Each leaf, 1.5 to 2.5 centimeters in length, is ovate, or triangular with a truncated or slightly cordate base, with coarse teeth. Borne in a raceme, initially compact but elongating with age, the flowers are pale blue to blue-violet, 2 to 3 mm in diameter, four-lobed with a narrow lowest lobe. Flower stalks are 0.5 to 2 mm.