Ontario Teachers' Manuals: Nature Study - Part 40
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Part 40

SMALL FRUITS

Study the method of propagating strawberries and such bush fruits as currants, gooseberries, raspberries, and blackberries. Reports issued from the Fruit Division of the Experimental Farm at Ottawa give information regarding the best varieties suitable for different parts of Ontario and Quebec. Have the pupils try propagating strawberries by taking the stolons or runners; currants and gooseberries, by means of layers or stem cuttings; and raspberries or blackberries, by root cuttings or the detaching of root shoots or suckers. Stem and root cuttings, when taken in the autumn, may be planted at once or may be stored in damp moss or sand in a cold cellar over winter. Stem cuttings should be about the size and length of a lead-pencil and root cuttings about half that size.

AUTUMN WILD FLOWERS

Observations made with garden flowers should be supplemented by observation lessons on a few selected wild flowers of the woods, fields, and roadsides. Although the spring months afford a much greater variety of wild flowers than do the autumn months, they do not afford quite as good an opportunity for finding and studying them. The woods and fields are drier and more easily reached in the autumn and the fall flowers last much longer. Some of the species seen blooming in spring and early summer are now in fruit and scattering their seed, so that the pupils have a chance to follow out the whole life history of a few chosen species. The pupils in this Form might select for special study the milkweed, worm-seed mustard, wild aster, and goldenrod. These should be observed out-of-doors, preferably, but suitable cla.s.s-room lessons may be taught by using similar matter.

MILKWEED

Taking the milkweed as a type, the following points are to be considered:

The kind of soil, where found, and whether in sun or shade.

Try to pull up a small-sized plant. Dig one up and notice the underground part.

Note the size of the largest plant seen, also the size of the leaves, and how they are arranged to prevent overshadowing.

Break off a leaf and note the white sticky juice, whence the name "milkweed". Discuss this milk as a protection to the plant.

Note time of first and last flowering of the plant and the colour and odour of the flowers. Watch insects gathering honey on a bright day.

Note the little sacks of pollen that cling to their feet. They sometimes get their feet caught in little slits in the flower and perish.

After the flowers disappear, note the forming of the little boat-shaped pods in pairs. Select one that is ripe and notice that it bursts along one side which is most protected. Open a pod carefully and notice how beautifully the flat, brown seeds are arranged in overlapping rows and how each seed has a large tuft of silky down that serves to carry it far away in the wind. This silk-like down is sometimes used to stuff cushions, and because of it the plant is sometimes called silk weed.

One species of b.u.t.terfly in particular feeds upon this plant--the monarch, or milkweed, b.u.t.terfly. This is one of the few b.u.t.terflies that birds do not eat. It is protected by a distasteful fluid. Look on the under side of the leaves of several plants until you find a pretty, pale green coc.o.o.n with golden dots, hanging by a thread-like attachment.

Early in the season the larvae may be found feeding on the leaves.

This plant is troublesome in some fields and gardens and so is cla.s.sed as a weed. When the stems come up in the spring, they are soft and tender and are sometimes used as pot herbs.

CORRELATIONS

Draw a leaf, a flower, a pair of pods, and a seed with its tuft.

Write an account of a visit to the woods to study wild flowers.

TREES

A study of the pines of the locality may be commenced in November, after the deciduous trees have lost their leaves and have entered their quiescent winter period. This is the time when the evergreens stand out prominently on the landscape, in sharp contrast with the other trees that have been stripped of their broad leaves and now look bare and lifeless. If no pines are to be found in the vicinity, cedar or hemlock may be subst.i.tuted. The lessons should, as far as possible, be observational. The pupils should be encouraged to make observations for themselves out of school. At least one lesson should be conducted out-of-doors, a suitable pine tree having been selected beforehand for the purpose. The following method will serve as a guide in the outdoor study of any species of tree:

THE WHITE PINE

Have the pupils observe the shape and height of the tree from a distance and trace the outline with the finger. Compare the shape of this tree with others near by of the same species and then with members of other species. Have the pupils describe in what particulars the shapes differ in different trees. They will come to realize that the difference in shape results from differences in length, direction, and arrangement of branches. They may notice that other evergreens resemble the pine in that the stems are all straight and extend as a gradually tapering shaft from the bottom to the top, that all have a more or less conical shape, and that the branches grow straight out from the main stem and not slanting off as in the case of the maples and elms.

Coming close to the tree, the pupils may first examine the trunk. By using a string or tape-line, they may find out how big it is around and the length of the diameter. Tell them how big some evergreens are (the giant trees of the Pacific Coast are sometimes over forty feet around).

Have them notice where the trunk is largest, and let them find out why a tree needs to be so strong at the ground. Heavy wind puts a great strain on it just at this point. Ill.u.s.trate by driving a long slat or lath into the ground firmly: then catching it by the top, push it over, and it will break off just at the ground. If a little pine tree could be taken up, the pupils would be interested in seeing what long, strong, fibrous roots the pine has.

Let them examine the bark of the trunk and describe its colour and roughness. The fissures in the bark, which are caused by the enlarging of the tree through the formation of new wood under the bark, are deeper at the bottom of the tree than at the top--the tree being younger and the bark thinner, the nearer to the top we go. How old is the very top, down to the first whorl of branches? How old is the stem between the first and second whorls? Between the third and fourth? Let the pupils find out in this way the age of a little pine that is regular and unbroken. The whorls of branches near the ground are usually small and dead in young trees and in old trees have completely disappeared. Relate the size of the trunk to its age, and also relate the size and length of the branches to their age. Where are the youngest branches and how old are they? What branches are oldest? Notice how the branch is noticeably larger just where it joins the trunk, as this is the point of greatest strain. Are the branches the same length on all sides of the trunk? If not, find one where branches are shorter on one side than on the other and try to discover the cause. Usually, if other trees are near enough to shade a certain tree, the branches are shorter and smaller on the shaded side.

Let the pupils look up into the tree from beneath and then go a little distance away and look at it. They will notice how bare the branches are on the inside, and the teacher will probably have to explain why this is so. They will discover that the leaves are nearly all out toward the ends of the branches. The leaves get light there while the centre of the tree top is shaded, and the great question that every tree must try to solve is how to get most light for its leaves. The pupils will now see an additional reason why the lower limbs should be longer than the upper ones. The greater length of the lower limbs brings the leaves out into the sunlight.

Why this tree is called an evergreen may now be considered. Why it retains its leaves all winter is a problem for more advanced cla.s.ses, but if the question is asked, the teacher may get over the difficulty by explaining to the cla.s.s that the leaves are so small and yet so hardy that wind and frost and snow do not injure them.

The pupils may each bring a small branch of twig back to the school-room, if the white pine is growing commonly about, otherwise the teacher may provide himself with a branch upon which to base another observation lesson in the cla.s.s-room.

If the tree has cones on it, an effort should be made to get a few, as they will also be considered in a subsequent cla.s.s-room lesson. If the cones have not yet opened when they are picked, so much the better, as they will soon open in a warm room, and the pupils will be able to examine the seeds and notice how they whirl through the air in falling.

If possible, let the pupils have an opportunity of seeing pine trees growing in the woods as well as in the open.

OUTLINE OF A CLa.s.s-ROOM LESSON ON THE WHITE PINE

~Inferences.~--If possible, each pupil is supplied with a small branch of the white pine and the teacher with a larger branch which can easily be seen by all the pupils. Before proceeding to examine the specimens, give the pupils a chance to tell what they now know about the white pine, and thus review the lesson taken out-of-doors. Then ask a few questions bearing upon their own observations, such as: What was the soil like where you found the pine tree growing? (They are found most commonly on light, sandy soil.) Did you notice any difference between the shapes of the pines in the deep woods and the pines in the open fields? Did you notice any dead limbs on those in the woods? Why did they die? The pupils may conclude that branches whose leaves cannot get the sunlight must die. Show that this causes knots in the lumber and exhibit samples.

This explains also why the trees of the forest have such tall stems without branches for a long distance up from the ground. They get the light only from above and seem to strive with the surrounding trees to reach it. If we want trees to grow tall, how should we plant them?

(Close together) What would such trees be good for? (Making timber or lumber) If we want trees to grow low and have thick and bushy tops, how should we plant them? (Far apart) What would such trees be good for?

(Their shade and their beauty) Good shade trees should be thirty to forty feet apart.

Ask the pupils if they have ever been near a pine tree when a gentle breeze was blowing, and have them tell the cause of the sound that they heard. They may decide that the shape and size of the leaves caused the sound when the wind was blowing through the tree top. Have them examine the branches in order to discover the following points:

LEAVES.--These are in bunches of five, two to three inches long, three-cornered, and with little teeth pointing toward the tip, light green near the tip of the bough (young leaves) and darker further down (older leaves); age of a leaf the same as the age of the wood it grows on, therefore some leaves are one year, some two, and a few three years old. No leaves on four-year-old wood, therefore the leaves fall off the white pine the third year. Ask pupils to try to find out by observation when the leaves fall off the pines. Note the fragrance of the leaves, and that they are sometimes put into "pine" cushions, also, how slippery they are to walk on.

BUDS.--These are found at the tips of the branches, one large one in the centre and several smaller ones grouped around it. Note their reddish-brown colour and that they are made up of scales overlapping and covered with gum which keeps out the rain, thus protecting the little growing tip inside. When buds grow, they become little twigs with leaves on. Find where the buds were a year ago. Notice the light colour of the twigs that grow during the present season and the darker colour of the twigs of the previous year. Where were the buds two years ago? What did the centre bud become? (A continuation of the stem) What did the other buds, called lateral buds, become? (New branches) Compare the growth made in different years.

Notice also how white the wood of the twigs is--the probable reason for calling it "white pine".

CONES.--Note the length and shape of the cones and how the seeds are placed in them inside the large scales. Get some of the seeds and note the wing-like attachment. Take the wing off a seed and drop it from a height at the same instant with one that has its wing attached. Note the whirling motion and infer what purpose the wing serves in scattering seed. Taste the kernel of a pine seed and discover why squirrels are fond of them. Burn a pine cone.

Find out what birds like to live in this tree. What has been noticed about them and their nests?

Have the pupils keep the seeds until the following spring by putting them in a box of dry sand and setting them in a cold place. They should then plant them in a corner where they can be partly shaded when the sun is bright. Plant them about half an inch deep and keep them watered if the weather is dry during the first summer.

NOTE.--The cones drop their seeds from high up in the tree so that the wind can carry the seeds long distances. The cones usually stay on the trees for a couple of years after they lose their seeds.

CORRELATIONS

Draw a pine tree, a bunch of pine needles, a pine cone, and a pine seed.

Write a description of a pine tree seen in the woods; also of one found in the open.

Write a list of things for which the white pine is useful.

_To the teacher._--The winter months, besides affording an opportunity for seeing trees and plants in their dormant or quiescent condition, also afford an opportunity for reading and reflection, for recalling observations and experiences of the past season, and for making plans for work and study in the school garden, woods, and fields when spring returns. The knowledge gained by the pupils through first-hand observation of trees, flowers, and gardens can be greatly extended by pictures and stories descriptive of these, which the teacher may from time to time bring to the school-room. Their personal experiences will be the basis for interpretation of many new things which will come up in the reading lessons, in selections which the teacher reads from week to week, and in books and papers which they themselves read in their homes.

Thus the interest that is aroused by the first-hand studies of plants in garden, orchard, or woodland will be carried over from autumn to spring, and the pupils, with the awakening of spring, will take up anew the study of plant life with a keener interest because of the time given to reading and reflection during the winter. Ill.u.s.trated magazines dealing with gardening and with the study of trees and plants, and such magazines as have a children's department, will prove of great a.s.sistance to the teacher who makes any serious attempt to interest pupils in plant studies. Stories of life in the woods and of plant studies suitable to young pupils should be used.

REFERENCES

Margaret Morley: _Flowers and their Friends._ Ginn & Co. 50 cents.

Margaret Morley: _Seed Babies._ Ginn & Co. 25 cents.