Purdue Extension: Plants we can do without

Invasive plants and poisonous plants are two groups of plants that hold little merit around our pastures, woodlands and homesteads. Proper identification and control of such plant species can reduce future challenges by reducing the spread of seed.

This article discusses some of the significant species that cause problems for Owen County. Proper identification is the key to developing a control plan.

Purdue Extension-Owen County is available to assist you in your identification efforts.

The bright yellow flowers that have stalks that can stand four feet tall and bloom in May might be those of cress-leaf groundsel. This winter annual germinates in late fall and has been dominant in several crop fields but can be a nuisance in hay production.

All plant parts have a toxin that persists after the hay is dried. The plant is opportunistic, growing in spots where vegetation is thin. Keep in mind that plant toxin is a function of the actual type of toxin, the quantity consumed, and the animal's size and health.

Poison hemlock is another plant thriving along roadsides, forest edges and in pastures. It is a biennial plant that grows vegetatively in year one and produces seed in year two. Bloom happens later this month, with the flowers looking similar to those of Queen Anne's lace or wild parsnip.

Purple spots on the stem differentiate it from other plants, and its height can be up to 10 feet. The first line of defense is seed control. With the plant this close to flowering, chemical control will not be as effective as when the plant is in early development.

Wearing gloves and avoiding contact with the plant is recommended when you handle this plant. A special publication, FNR-437H, outlines chemical control methods and can be found online at purdue.edu or email luzar@purdue.edu to request a paper copy.

Another nasty, poisonous plant listed in the publication WS-37 is white snakeroot. This plant can grow up to four feet tall and contains the toxin Tremetone, which can pass through milk. You do not want this plant in your pasture or hayfield.

A final "oddball plant" that is a hedge plant and is extremely toxic when clippings are consumed is the yew shrub. In areas where pastures border housing one must be careful that a neighbor does not trim the yews and toss clippings into the pasture. I have worked with clients who found a ewe dead from consuming yew trimmings.

Another poisoning possibility is wild cherry limbs breaking off and leaves being consumed by cattle. Site awareness is important and identifying potential hazards can pay dividends.

Again, contact Purdue Extension-Owen County at 812-829-5020 if you want assistance identifying "problem" plants.