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Cat-tail flag in blossom. The staminate flowers are massed at the tip, and the pistillate flowers which form the "cat-tail" are massed lower down on the stalk. Photo by Verne Morton. |
In June and early July, if the cat-tail be closely observed, it will be seen to have the upper half of the cat's tail much narrower and different in shape from the lower half—as if it were covered with a quite different fur. It seems to be clothed with a fine drooping fringe of olive-yellow. With the aid of a lens, we can see that this fringe is a mass of crowded anthers, two or three of them being attached to the same stalk by a short filament. These anthers are packed full of pollen, which is sifted down upon the pistillate flowers below by every breeze; and with every puff of stronger wind, the pollen is showered over all neighboring flowers to the leeward. There is not much use in trying to find the pistillate flowers in the plush of the cat-tail. They have no sepals nor petals, and are so imbedded in the thick pappus which forms the plush that the search is hardly worth while for nature-study, unless a microscope is used. The ovary is rather long, the style slender, and the stigma reaches out to the cut-plush surface of the cat-tail. The pupils can find what these flowers are by studying the seed; in fact, the seed does not differ very much from the flower, except that it is mature and is browner in color.
A cat-tail seed with its balloon. |
It is an interesting process to take apart a cat-tail plant; the lower, shorter leaves surround the base of the plant, giving it size and strength. All the leaves have the same general shape, but vary in length. Each leaf consists of the free portion, which is long and narrow and flat towards its tapering tip but is bent into a trough as it nears the plant, and the lower portion of the leaf, which clasps the plant entirely or partially, depending upon whether it is an outer or inner leaf, and thus adds to its strength. We almost feel as if these alternate leaves were consciously doing their best to protect the slender, flower stem. The free part of the leaves is strengthened by lengthwise veins, and they form edges that never tear nor break. They are very flexible, and therefore yield to the wind rather than defy it. If we look at a leaf in cross-section, we can see the two thick walls strengthened by the framework of stiff veins which divide the interior into long cells. If we cut the leaf lengthwise we can see that these long cells are supported by stiff, coarse partitions.
Where the leaf clasps the stem, it is very stiff and will break rather than bend. The texture of the leaf is soft and smooth, and its shade of green is attractive. The length of the leaves is often greater than that of the blossom stalk, and their graceful curves contrast pleasantly with its ramrod-like stiffness. It is no wonder that artists and the decorators have used the cat-tail lavishly as a model. It is interesting to note that the only portion of the leaves injured by the wind is the extreme tip.
The cat-tail is adapted for living in swamps where the soil is wet but not under water all the time. When the land is drained, or when it is flooded for a considerable time, the cat-tails die out and disappear. They usually occur in marshy zones along lakes or streams; and such a zone is always sharply defined by dry land on one side and water on the other. The cat-tail roots are fine and fibrous and are especially fitted, like the roots of the tamarack, to thread the mud of marshy ground and thus gain a foothold. The cat-tails form one of the cohorts in the phalanx of encroaching plants, like the reeds and rushes, which surround and, by a slow march of years, finally conquer and dry up ponds. But in this they overdo the matter, since after a time the soil becomes too dry for them and they disappear, giving place to other plants which find there a congenial environment. The place where I studied the cat-tails as a child is now a garden of joe pye weed and wild sunflowers.
Reference—Plant Life, Coulter.
Cat-tails sending off their seed-balloons. Photo by Verne Morton. |
Leading thought—The cat-tail is adapted to places where the soil is wet but not under water; its pollen is scattered by the wind, and its seeds are scattered by wind and water. Its leaves and stalks are not injured nor broken by the wind.
Method—As this is primarily a geography lesson, it should be given in the field if possible; otherwise the pupils must explore for themselves to discover the facts. The plant itself can be brought into the schoolroom for study. When studying the seeds, it is well to be careful, or the schoolroom and the pupils will be clothed with the pappus for weeks.
Observations—
1. Where are the cat-tails found? Is the land on which they grow under water all the year? At any part of the year? Is it dry land all the year? What happens to the cat-tails, if the land on which they grow is flooded for a season? What happens to them, if the land is drained?
2. How wide a strip do the cat-tails cover, where you have found them? Are they near a pond or brook or stream? Do they grow out in the stream? Why do they not extend further inland? What is the character of the soil on which they grow?
3. What sort of a root has the cat-tail? Why is this root especially adapted to the soil where cat-tails grow? Describe the rootstock.
4. The cat-tail plant. Are the leaves arranged opposite or alternate? Tear off a few of the leaves and describe the difference between the lower and the upper end of a leaf as follows: How do they differ in shape? Texture? Pliability? Color? Width? Does each leaf completely encircle the stalk at its base? Of what use is this to the plant? Of what use is it to have the plant stiffer where the leaves clasp the stalk? What would happen in a wind storm if this top-heavy, slender seed stalk was bare and not supported by the leaves? What is the special enemy of long, tall, slender-leafed plants?
5. Take a single leaf, cut it across near where it joins the main stalk and also near its tip. Look at the cross-section and see how the leaf is veined. What do its long veins or ribs do for the leaf? Split the leaf lengthwise and see what other supports it has. Does the cat-tail leaf break or tear along its edges easily? Does the wind injure any part of the leaf?
6. Study the cat-tail flowers the last half of June. Note the part that will develop into the cat's tail. Describe the part above it. Can you see where the pollen comes from? The pistillate flowers which are in the plush of the cat-tail have no sepals, petals, odor nor nectar. Do you think that their pollen is carried to them by the bees? How is it carried?
7. Examine the cat-tail in fall or winter. What has happened to that part of the stalk above the cat-tail where the anthers grew? Study two or three of the seeds, and see how they are provided for traveling. What scatters them? Will the cat-tail seed balloons float? Would the wind or the water be more likely to carry the cat-tail seeds to a place where they would grow? Describe the difference between the cat-tail balloon and the thistle balloon.
8. How crowded do the cat-tail plants grow? How are they arranged to keep from shading each other? In how many ways is the wind a friend of the cat-tails?
9. How do the cat-tails help to build up land and make narrower ponds and streams?