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The teacher brought out that the ear with the largest number of grains of corn to germinate was the best ear for seed. As the corn was shelled, the children noticed the position of the grains in the row. "Notice the size and shape of different grains. In which ear do you think there is most corn? Why? Notice the scar left on the cob. Which do you think is better, a large cob or a small one? Why?"
We next made a study of a grain of corn. We took some dry corn and some corn that had been soaked in warm water over night. The children looked at the grain of dry corn and noticed the part that was joined to the cob. "Notice the dent in one side," said the teacher. "Take a grain of soaked corn. What is the first part of the corn that you see? Take off the seed coat and note the germ. Remove it with a sharp pointed knife." They then took the corn that had been between damp sheets of blotting paper, and found germination further advanced. The teacher had them take the germ from the corn and see if it would grow without the rest of the grain of corn. After a few days: "Did it grow? What part of the corn then is the essential part?" They observed it for a few more days: " What has happened to our corn? Why do you suppose it died? What do you thing was in the part we removed? How did the bean carry its food?" The children learned that corn has two supplies of food—cotyledon and endosperm. They noticed the radicle as it emerged, then the plumule. "Which came out first? Note the grains of corn planted in damp sawdust. Note the position of the plumule, of the radicle. Where is the grain of corn? Where was the germ when it germinated?"
We thought it interesting to see how our plant grew. We took the corn that had been planted between pieces of damp blotting paper. The plumule and radicle had both emerged from the grain of corn. With pen and ink we made horizontal marks around the root and the stalk of the com one-sixteenth of an inch apart. We had to be careful to put a mark on the very tip of the root and of the stalk. In the morning there was a surprise for us. We marked again, to be sure we were observing correctly. We saw that we put a mark on the very tip of the root. We examined the plant again next morning. "Were we right? How does the root grow? How does the stalk grow?" The term "growing tip" was then taught. We examined the growing tip and found it very tender. In considering what kind of soil is needed for the little root to push its way tbrough, we found one more good reason why the seed bed should be thoroughly pulverized. We made drawings of corn: First the dry grain, then the soaked grain, then grain with the root peeping out, grain with the root and plumule both out well, and after an interval of a few days a grain with the growth of both plumule and radicle well started.
The next step was to consider how close we should plant our corn. The children examined a picture of corn, with its immense root system. "What do plants have to have? Air, heat, light, moisture. With what must we provide our corn in the field? What will happen if we plant our corn too close together?" The boys measured the rows of corn at home and found how far apart they were, as well as how far apart the stalks of corn were in the row. "Why do you suppose your father made his rows so far apart? So the plants would get sunshine and air. But there is another good reason. How does your father cultivate his corn? What would happen to his corn if he got it too close? How are we going to cultivate our corn? Do you think that for this reason we could plant ours a little closer? Suppose we plant our corn in rows 2 feet apart and in hills 1£ feet apart. Now, how many grains shall we put in a hill? What must we think of? Which would be easier, to pull up a stalk or two of corn or to have to plant over again?" We decided to put five grains of corn in a bill. With yardstick and chalk we marked off rows 2 feet apart on the floor of the veranda and indicated the position of the hills. "How many hills will there be in each row? How many grains of corn needed for one row? For two rows?"
When the soil was in readiness we laid off rows 2 feet apart with the help of the garden line. We dropped seed 18 inches apart in drill, as we had decided. As the seed were dropped, the barefoot children pressed them down firmly into the soil. They did this because they were told that soil fitting closely around a seed will keep it moist, and a seed requires moisture to germinate. They covered over with soil, pressing the earth firmly against the corn. The top soil was left soft and loose.
The children watched the first tiny leaf come out. They noticed where the seed was and compared it with the bean, which they had previously studied. They noted the growth of corn, how one leaf unfolds, showing another one curled and ready to unfold, and so on.
The children were instructed that they could not begin to cultiA-ate corn too soon. "We must keep our top soil soft and loose," the teacher told them. "Why? Suppose we try this experiment." Into a shallow box we put some moist soil. Over part of it we put a layer of dry dust from the road. We then set it in the sun for a day or two, and finally removed the dry dust to look at the soil. "Which shows more moisture, that covered by the dust or that left bare? Why did the water in the bare soil evaporate more quickly? Can you give a good reason now for keeping a layer of pulverized soil on top of our garden?" Thus the expression "dust mulch" was taught. We looked at earth under planks, boards, and stones, and the children learned that it was moist because the stone and board act exactly as a dust mulch.
From our experiments we learned that water rises in soil. Questions that we investigated were: "In what kind of soil does it rise more readily—firmly packed or loose, lumpy or well pulverized? Which of these soils dries out more readily? In what condition should we keep the soil around our corn? Into what kind of soil did water sink more readily? Would it be wise to have our soil in a suitable condition for the water to sink into?" We considered again the immense root system of the corn and noted the fine mat of roots near the surface of the-ground. The children were cautioned against cultivating the corn too closely after it had grown large enough to have these roots.
The children kept a record of all the experiments performed and of the planting and cultivation of the corn. They also made a record of all the animals and insects that molested the corn.
One morning we found traces of a mole. We dug into a burrow, but could not find the mole. Later one of the children brought a mole caught at home. We then made a complete study of the mole, and afterwards of the corn worm, which is really not a worm at all, but a larva.
The children noticed smut on the corn and read that it was best to burn the stalk infested with this disease to keep it from spreading all over a field.
We found other enemies of the corn: Weeds and grass had made their appearance. We learned that they hurt our corn by taking from the soil the food and moisture that it might have; they kept light, air, and sunshine from corn.
We learned the names and habits of the weeds and grasses found in the garden and studied how to get rid of them. AVe decided that to get rid of them we must first know how they made new plants. Some had only seed. Some had seed and sent down a tap root that lives all winter. The quack grass had seed, but would grow from cuttings and keep alive all winter. We made drawings and blue prints of the following weeds and grasses: Pig weed, lamb's quarter, joint grass, purslane, ragweed, dog fennel, plantain (3 varieties), pepper grass, shepherd's purse, jimson weed.
"How did these weeds come to be in our garden? From seed. AVe did not plant them. Who did plant them? Some sowed themselves. The wind, birds, animals helped others. Suppose we try to find out how many seed are in one plant." The teacher pulled up a plant of .shepherd's purse and gave a branch of it to each child. We counted the number of seed pods on each branch. We put the number down with a sharp stick on the ground and added. Then we counted the number of seed in one pod. "How many pods? How many seed in one pod? How shall we find out how many seed altogether? Multiply." AVe did so, and found that there were practically 4,000 seed on the one plant of shepherd's purse. "How many seed