Field Guide

Large stands of wind-pollinated giant ragweed commonly form in disturbed areas, causing late-summer misery in the form of hay fever for many Missourians.

Tickseed sunflower has flattened black seeds that attach themselves to clothing and pets via two needlelike awns. In flower, it grows in massive displays in moist bottomlands.

Wood nettle, or stinging nettle, often forms dense stands in bottomland forests, streamsides, and other places. There, canoeists, anglers, and others try to avoid touching its stinging hairs!

Horseweed looks something like a goldenrod, except that the tiny composite flowers are not yellow. Instead, they are cream-colored and rather drab. In Missouri, this plant is especially associated with disturbed habitats and is a troublesome crop weed.

You may not recognize elephant’s foot as a member of the daisy or sunflower family because it lacks petal-like ray florets. Also, it has unusual, doubly compound flower clusters. And how did it get its name, anyway?

White heath aster is one of Missouri's most widespread and weedy native asters. It grows in uplands, bottomlands, and nearly all habitats in between. It has a shrubby, wide-branching habit, and the stem leaves are thin and needlelike.

Named for its resemblance to a European herb that was popular in Medieval times, golden Alexanders is a native Missouri wildflower with bright yellow flowers arranged in umbrella-like clusters.

Full grown, water hemlock looks something like a gigantic Queen Anne's lace, but this common, widespread member of the carrot family is the most toxic plant in North America. All parts are deadly. A piece of root the size of a walnut can kill a cow-sized animal.

Water smartweed can live submerged in water, or on wet banks or other soggy ground, yet it can also live in merely moist areas. The stems often sprawl as they grow, taking root at the swollen nodes. The small, pink flowers develop in long, erect clusters.

Johnson grass is a native of the Mediterranean that is invasive in our country. It’s a weed that infests cropland and degrades native ecosystems, and heavy infestations are found in all the major river bottoms of Missouri.