Filtered (38)
Stinging nettle plants are dioecious (unisexual) with male (staminate) and female (pistillate) flowers on separate plants. Flowers occur in knobby clusters (panicles) that arise from the leaf axils. Neither pistillate nor staminate flowers have any petals. Staminate flowers have four light green, identical sepals cupping four short stamens. Pistillate flowers also have four sepals but two are narrowly lance-shaped, about a millimeter long, and free, alternating with two sepals that are 1.4-1.8 mm long and cupped around the ovary; styles are absent but the single stigma is long and feathery. The fruit is a flattened, oval to egg-shaped seed, less than 1/16" long.

Urtica

Urtica dioica

stinging nettle [Blooms: Jul-Aug]

Thyme-leafed speedwell's upper stems host clusters (racemes) of flowers 2-7" long; flowers may either be opposite or alternate along the stem. Each flower is 1/8-1/4" across with a short (1/4"), slender petiole; at the base of the petiole is an oblong, hairless, leafy bract also about 1/4" long with smooth margins. (Thus, the flowers effectively arise from leaf axils.) Individual flowers consist of a green calyx with four triangular lobes shorter than the petals; a short corolla with four oval petal-like, lobes (the lowest one smaller than the other three); two stamens with purple or white anthers; and a green ovary with a single style. The lobes (petals) are white or pale blue, usually with dark blue lines radiating from the flower's center on the upper three lobes. The fruit is a laterally flattened, heart-shaped capsule 1/4" across with two chambers and a fringe of glandular hairs. When mature, the chambers split open, releasing 50-72 tiny seeds. There are 16 species of the genus Veronica reported from Illinois. I have only seen three (Veronica arvensis, Veronica polita, and Veronica serpyllifolia) in Jackson Park but, given their minute size and inconspicuousness, it seems likely that more remain to be found.

Veronica

Veronica serpyllifolia

thyme-leafed speedwell [Blooms: Apr-?]