Materials.—A milkweed pod; a ripe dandelion head.
Introduction.—A short conversation about the effects of the crowding of plants, as carrots and turnips, in a garden plot, and hence the need for the scattering of seeds.
Observations.—Open a milkweed pod in the presence of the class, so that they may see how the pod opens, how beautifully the seeds are arranged, and how the silk tufts are so closely packed in together.
Allow a pupil to lift a seed out, blow it in the air, and observe how the silk opens out like an umbrella. Distribute seeds, one to each pupil. Ask the pupils to find out why this little airship is able to carry the seed. They will find that the seeds though broad, are thin and light, and the silky plumes very light.
Ask the pupils to release their milkweed seeds at recess, when out of school, and find out how far they can fly. This is an interesting experiment for a windy day.
The white balls of the dandelion are next examined, the tiny seeds are found standing on tiptoe on a raised platform, each grasping a tiny parachute and waiting for a puff of wind to start them off. A pupil is permitted to give the puff. Seeds are distributed, and the means of flight is compared with that of the milkweed. The shape of the seeds is observed and also the tiny anchor points at the lower end of the seed for clutching the ground when the seed alights.
Another lesson on seeds that fly can be based on the study of tree seeds, using those of the maple, elm, basswood, pine, and spruce.
CORRELATIONS
1. Drawing of milkweed pods and seeds, and drawing of the dandelion seed-ball and the seeds when floating in the air.
2. Reading and literature. Interpret the thought and read expressively: