February 11, 2004 | By: Aimee D. Heald

Thousands of plant samples, some dating back to the late 1800s, are stored at the University of Kentucky College of Agriculture Herbarium. Even the oldest plants are fully intact and still used by agronomists to identify weeds, grasses and crop plants in the Commonwealth.

UK Extension Weed Science Specialist J.D. Green is in charge of the herbarium and he believes it provides a valuable service to Extension professionals and clientele. County Extension agents and others send in more than 300 samples each year in hopes of finding out more about the plants’ characteristics and, if necessary, how to control them.

“One of the key aspects of the weed science herbarium is to identify a plant at the early growth stage so we can develop a good control strategy,” he said. “We get plants at all different growth stages. Sometimes we have to ask the individual to send us another sample, since some plants are easier to identify when they become more mature. One of the key aspects of developing control recommendations is to adequately identify the problem.”

When a sample arrives at the herbarium, Green identifies it and then makes any needed control recommendations to the person who submitted the plant sample. Plants are pressed between sheets of newspaper and dried before they are stored in one of cabinets, grouped according to plant families.

“Another purpose of the herbarium is to try to keep track of federal noxious weeds or other invasive plant pests,” Green said. “I have a list of federal noxious plants to watch for. In fact, National Invasive Weed Awareness week will be observed Feb. 23 through 27, 2004 in Washington D.C. It’s very important that we keep invasive exotic plants from becoming widespread or entering the state.”

Green said some invasive plants already exist in Kentucky and there are a few other plants he’s got his eye on that have not yet been found in the state

The College of Agriculture Herbarium dates back to the 19th Century when Harrison Garman came to UK as the head of the zoology and entomology department in 1887. He began cataloguing plants and insects in Illinois prior to that time. Green said some of Garman’s early plant collections from 1870 to 1880 began the UK College of Agriculture Herbarium.

Most of his collections were from Kentucky; however he did collect specimens from other areas of the country, including the oldest specimen in the collection from the Rocky Mountains, which dates back to 1862.

Many of the plants in the herbarium are considered undesirable plants or weeds, but Green said not all undesirable plants are pests.

“Some plants I would consider as weeds are used for forage crops or landscaping,” he said. “A desirable plant to some folks may be a curse for others; it all depends on where it’s growing, and whether or not it is aggressive.”


Writer: Aimee D. Heald 859-257-4736, ext. 267
Source: J.D. Green 859-257-4898