Learning the plants' processes of making food
All about plant life
The best way to study plants is to cultivate a garden. If that is not possible, raise indoor plants in pots, and window boxes.
Wouldn't you like to know what happens to the seeds after you have placed them in the dark soil? You can't pull up the plants and still have a garden, but you can make an interesting experiment. If you will plant a lima bean in a glass-sided box you may watch it grow into a mature plant.
Green plants are nature's miracle workers. The leaves of that plain little bean, the leaves of all green plants, are most amazing chemical factories. Turning sunlight, air, and water into sugar and starch, they manufacture food not only for themselves but indirectly for all animal life. Look at a leaf through the microscope. You can see the tiny green dots of chlorophyll and the little mouths, or pores, through which the leaf breathes in the carbon dioxide and breathes out moisture and oxygen.
Plant must also have water and certain minerals carried in the water. Look at the root of your bean plant through the microscope. Those tiny hairs absorb water and dissolved minerals out of the soil. Little pipes carry the water up through the stems of the plant to the leaves. Other pipes carry the sap, containing dissolved plant food, back from the leaves to the stem and roots.
Plants Make Food for All Animals
Plants make food for all animal life. Even meat-eating animals depends upon green plants. You would have no beefsteak if there were no grass for cattle to eat. Owls eat field mice; daddy longleags eat aphids. But field mice live on grain, and aphids eat green plants. Without plant, there would be nothing for the meat eaters to feed on.
Since all life depends upon the work of the green leaf, it should be interesting to make a collection of leaves. Learn to recognize the trees and shrubs in your neighborhood by their leaves. Learn the names of the weeds in your garden, lawn, and neighboring pasture, or woodlot.
Some green plants are so small or so unlike the familiar flowering plants that you may not yet be acquainted with them. The scum on quiet pond water is made up of colonies of plants called algae. If you have ever looked at the beautiful patterns of algae through a microscope you will never again think of scum as something ugly or unclean.
Another lowly but useful and interesting group of plants are the mosses. They too are very beautiful under the microscope. The algae and mosses were among the first plants to develop on the earth. This prepared the way for the higherplants.
How Nongreen Plants Get Their Food
All the plants we have been talking about contain chloropyll. Many plants, however, lack the magic greenness. They must obtain their food from dead plants and animal matter or from the living tissues of animals and green plants. In you walks through the woods you will find lichens and bracket fungi growing on tree trunks. Down under the damp leaves are mushrooms and toadstools. Perhaps you will find some of the "ghostflowers" - the Indian pipe, cancerroot, bechdrops, and coralroot - or the dodder, which wraps its stringy vines around other plants. Look at the dodder carefully and see how it thrusts suckers into the stem of its host, draining the food made by the green plant.
The fungi are a large and varied family. Some of them cause bacterial diseases of animals and human beings. Others are the destructive muts and rusts that attack plants. Some fungi, however, are very useful. One of them is yeast, which extracts oxygen for its own use from sugar in bread dough. Another is mold. Through your magnifying glass look at the strange blue forest on a piece of mold bread. It is related to the wonder drug penicillin.