Field Guide

Johnny-jump-up is a flat-faced violet whose small flowers are a washed-out blue or violet with a very light yellow or white center. Look for it in fields, meadows, glades, rights-of-way, disturbed sites, and possibly your front lawn.

Mullein immigrated to America along with Europeans, and with them it has spread across the continent. Its fuzzy, green-gray rosettes of leaves and tall spikes of yellow flowers make it easy to identify.

Moth mullein is a native of Eurasia introduced to our continent in the early 1800s. Since then, it has spread across North America. It’s named because the fuzzy flower, with 2 antennalike stamens, looks something like a moth.

Although the funnel-shaped, 5-lobed flowers look something like the petunias you find at garden centers, our wild petunia is not related to them. This ruellia often has crinkled hairs in 2 narrow, lengthwise bands on opposite sides of the stalk.

When you consider the negative effects this plant has on natural habitats, and how hard it is to control or eradicate, you almost want to rename it “leafy scourge”! This invasive plant is spreading in our state. Learn how to identify it.

The flowers of dayflower are truly blue, and they have only two conspicuous petals. A fast-growing, sprawling, but shallow-rooted weed, this introduced species commonly annoys gardeners.

A spiny annual with bright yellow flowers and dandelion-like leaves, buffalo bur is an introduced member of the nightshade family.

A biennial plant with bristly hairs and usually with single stems, viper’s bugloss can grow 2½ feet tall. The flowers are pink in bud, blue to ultramarine later. The protruding stamens are pink.

Square, unbranching stems, opposite leaves, two-lipped flowers, and a mild minty fragrance are clues Ohio horsemint is in the mint family. Tight, rounded flower clusters are stacked atop one another at the stem tips.

A square-stemmed plant with opposite leaves, self-heal bears two-lipped blue, lavender, or violet flowers in a cylindrical head. We have two varieties of self-heal in Missouri, one native and one introduced.