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Mary Agnes Chase b. 1869

AGROSTOLOGY/GRASSES

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DAUGHTER OF A BLACKSMITH

In 1869, Mary Agnes Meara was born in Iroquois County in Illinois. Mary’s father was a railroad blacksmith and her family changed their last name to Merrill to avoid the prejudice faced by working-class Irish immigrants. He died when she was only two years old and her family moved to Chicago. Mary’s family was poor, so when she finished grade school, she had to go to work at the newspaper to support them and wasn’t able to continue her formal education.

THE EXPOSITION

When she was only nineteen, Mary married a man in the newspaper business and changed her name to Mary Agnes Chase, but her husband died of tuberculosis a year later. In 1893, Mary and her nephew attended Chicago’s Columbian Exposition, which was a huge fair, and saw an exhibit about plants. Mary was so fascinated by what she learned there that she decided to study botany.

A TALENTED ARTIST

Mary started her own field journals about plants and one of her professors was so impressed with her drawings that she was hired to illustrate books. She learned to use a microscope and worked as a meat inspector at the Chicago stockyards before returning to work with plants at the Chicago Field Museum. Eventually, she got a job with the United States Department of Agriculture, where she worked her way up from illustrator to lab assistant to principle scientist in charge of agrostology, the study of grasses. She traveled the world collecting more than 20,000 species of grasses and was the first to document several them.

A HUMAN RIGHTS ADVOCATE

Throughout her career, Mary Agnes Chase worked tirelessly to make science accessible and understandable to everyone. Sometimes, she risked her career to speak up for human rights. In addition to mentoring underprivileged students, including women who wanted to be botanists, she was a suffragist who was arrested twice, protesting for women’s right to vote.

A COLLEGE DEGREE

In her long career, Mary Agnes Chase published more than seventy articles and books, including a popular guide to grasses for nonprofessionals, called Agnes Chases’s First Book of Grasses, which is still in print. When she was eighty-nine years old, she finally received her first college degree, an honorary degree from the University of Illinois.

IN TODAY’S WORLD

The study of agrostology is still important today. Crop plants such as rice, corn, wheat, and sugarcane are all grasses. Healthy grasslands prevent soil erosion, and help with the problem of climate change by soaking up carbon dioxide from the air.

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AGROSTOLOGY/GRASSES

Mary Agnes Chase traveled the world and collected over 20,000 species of grasses. If you can’t go on a grass-collecting expedition of your own, try your hand at growing grass in clear plastic bags and flowerpots under different conditions to watch seeds germinate, and see what happens when grass grows in the dark.

MATERIALS

  • Paper towels
  • Water
  • Small plastic zipper bags
  • Grass seed such as lawn grass, wheat, oats, barley
  • Permanent marker
  • Masking tape
  • Dirt or potting soil
  • Small flowerpots or paper cups
  • Clear glass container, such as a large glass jar to put over one pot (optional)

PROTOCOL

GERMINATION

1 Dampen a paper towel with water, fold it, and put it in a small zipper bag.

2 Add a few grass seeds to the bag on one side of the paper towel. Partially close the bag, but do not seal completely. Plant more than one type of grass, if you’d like to compare. Fig. 1.

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Fig. 1. Plant grass seed in plastic bags on damp paper towels.

3 Label the bag with a date and the type of seeds you planted.

4 Use tape to hang the bag in a window so you can see the seeds.

5 Check the seeds every day to observe germination. Watch for roots and a sprout to emerge. Fig. 2. Plant the same type of seeds in pots to compare how they grow. Fig. 3, Fig. 4.

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Fig. 2. Observe germination, watching for roots and a sprout to emerge.

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Fig. 3. Plant the same types of grass seeds in pots to see how they grow in dirt.

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Fig. 4. Compare growth rate and appearance in dirt to that in plastic bags.

GROWTH CONDITIONS

1 Add dirt or potting soil to several small flowerpots or paper cups.

2 Plant the same type of grass in each pot by sprinkling grass seed on the dirt and then covering it with a thin layer of soil, or follow instructions on the seed packaging.

3 Label each container with growing conditions you choose, such as no sun, full sun, daily water, no water, and glass covering. Fig. 1.

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Fig. 1. Grow grass under different conditions.

4 Add a glass or plastic covering to one pot to create a greenhouse that traps heat and moisture. Fig. 2.

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Fig. 2. Cover one container with glass or plastic

5 Allow grass to grow for several days, observing it daily for a week or two. When it is fully grown, compare the appearance of the grass which grew under different conditions. Fig. 3.

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Fig. 3. Compare germination rate and appearance of grass grown under different conditions.

6 Place grass grown in the dark in a sunny spot to see how long it takes to turn green.

CREATIVE ENRICHMENT

Go outdoors and collect several grass-like plants, pulling them up from the roots, if possible. Cut the stems with scissors to identify whether they are grass, rushes, or sedges (see The Biology Behind the Fun, below). Fig. 4, Fig. 5.

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Fig. 4. Pull some grass up by the roots and study it.

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Fig. 5. Find the nodules, or “knees,” of the grass.

THE BIOLOGY BEHIND THE FUN

Grasses use a chemical process called photosynthesis to turn sunlight, water, and carbon dioxide into energy so they can grow. Chlorophyll is a green pigment in plants which helps them absorb sunlight. Most plants growing in the dark don’t make much chlorophyll.

If you see a grass-like plant, remember this rhyme: “Sedges have edges. Rushes are round. Grasses have knees that bend to the ground.” Plants called sedges and rushes have solid stems and as the rhyme says, cutting a sedge reveals a triangular stem and cutting a rush stem will yield a round shape. The stems of grass are hollow, with joint-like solid nodes, which the rhyme calls “knees.” The grass family, called Poaceae, contains around 780 genera and 12,000 species (see Lab 2). It is one of the most important plant families for humans, because we frequently consume grains from grasses, including wheat, rice, corn, and barley. Cattle eat an enormous amount of grass as well.

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