Field Guide

Canada thistle is a native to Eurasia and arrived on our continent probably before the Revolutionary War — most likely mixed in agricultural seed. A bad weed of crop fields and rangeland farther north, it causes problems in Missouri, too.

Anyone who’s seen what purple loosestrife has done to New England and the Northeast can tell you how invasive this plant is. Learn how to identify it, so you can report any findings to the Missouri Department of Conservation.

Running buffalo clover spreads by sending out long, creeping runners. Now endangered, this native perennial once flourished along streams and buffalo trails throughout the grasslands of the eastern and central United States.

In early spring, henbit carpets entire fields with the pinkish-purple of its small flowers. This nonnative mint spreads abundantly but causes few problems. It has shallow roots and fades before crops begin to grow.

A big river floodplain species, decurrent false aster has declined as wetlands have been drained and converted to agricultural crop production.

Dwarf larkspur is a single-stemmed perennial with an upright flower stalk bearing racemes of bluish-purple flowers. Like other larkspurs, there is a spurlike appendage behind each flower.

Small blue, lavender, or white flowers shaped like cornucopias dance along the tall stems of this Carolina larkspur, which grows in prairies and grasslands.

Ground plum is a legume that bears plumlike, edible fruits. Its short, spikelike clusters of pea flowers can be white, cream, yellow, pink, or violet.

As pretty as this wildflower is, the common name “Jacob’s Ladder” comes from its ladderlike leaves, which made people think of the story from Genesis in which Jacob dreams of a ladder reaching up to heaven.

Of the many invasive nonnative plants that were originally introduced to stop soil erosion and improve soils, kudzu is one of the worst. This “vine that ate the South” is often the first plant that comes to mind when we think of “invasive plants.”