How Plants Protect Themselves and Famous Women Botanists

At Cogitania’s Saturday Botany workshop fourth graders learned about how plants protect themselves from predators. Plants can't run away from danger like animals can, so they have developed their own defenses to protect themselves. A plant's main predators are the animals that feed on them. These range from tiny insects that chew their way through leaves to large mammals that eat whole plants. To defend themselves plants use thorns, hair, spines, and chemicals to keep predators away. Other plants send out chemicals into the air to attract predators that then visit the plant to eat hungry insects.

We read about famous women Botanists that lived in the 1800s and 1900’s and how they contributed to the Botanical and Horticultural fields. Josephine Milligan (circa 1889) collected plants throughout the United States and kept a home herbarium of wildflowers which was later donated to the Smithsonian Institution after her death. M. Alice Cornman (circa 1918) began writing descriptions and copying data for Botanist Ellsworth P. Killip which led to her collecting plants herself in Guatemala and Panama. Velva Elaine Rudd (circa 1949-1999) served as a curator in the Department of Botany, U.S. National Herbarium from 1959 to 1973. She also researched and published extensively on tropical species.

Finally, for the hands-on activity, which is the students favorite part of the class, we did an experiment to learn about how the xylem carries water to all parts of a plant. To demonstrate this we soaked celery stalks in 4 glasses of differently colored water. After about 1 hour we observed how the colored water moved up the xylem and to the celery leaves at the top of the stalk.

Instructor: Nathan Emerson