Handbook of Nature-Study · Lesson CLXVI · Topic 25: Farm and garden crops
166. The clovers
Goal: Your child digs up a clover root, finds the little swellings on it, and explains how clovers feed the soil and depend on bees.
You'll need
- Nature notebook, pencil and colored pencils
- A hand lens (magnifying glass)
- A trowel
- A bucket of water to wash a root
What's in the book
A Teacher's Story about the clovers and alfalfa and the lesson: Leading thought, Method and eight questions.
The lesson, step by step
When and where
Clovers bloom from late spring through summer in lawns, pastures, hayfields and roadsides. Comstock's method: each child digs up a red clover or alfalfa root. Keep shoes on in clover: bees are working there.
The leading thought
The clovers enrich with nitrogen the soil in which they are planted. They are very valuable as food for stock; and their flowers are pollenated by bees.
How many kinds?
How many kinds of clover do you know? How many of the medics?
Look for red clover, white clover, alsike (pinkish), sweet clover (tall, Lesson CLXVII), and the small yellow medics.
Which flowers first?
In all clovers, which flowers of the head blossom first, those on the lower or outside, or those on the upper or inside?
The root nodules
Take up a root of red clover or alfalfa, noting how deep it grows. Wash the root free from soil, and find the little swellings on it.
Swish the root in the bucket and look with the lens. Say: Inside those little swellings live tiny living things called bacteria. They take nitrogen from the air in the soil and turn it into plant food. When the clover dies, that food stays in the ground for the next crop.
Clover and the farm
How do clover roots protect the land from being washed by heavy rains?
Upon what insects does the red clover depend for carrying pollen? Can it produce seed without the aid of these valuable bees? Why not?
Nature notebook
Draw a clover plant with its root and the little nodules on it, and a flower-head. Write one sentence about why farmers plant clover. Wash hands when you come in.
Answers to the book's problems
Bumblebees carry pollen for red clover; its flower tubes are too deep for most other bees to reach the nectar, so without them it sets little seed. A cover crop is a crop grown to cover and protect the soil, and clovers also add nitrogen to it.
Worked out for this site from the scan. If a number in your copy differs, trust the book.