Ontario Teachers' Manuals: Nature Study - Part 41
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Part 41

Margaret Morley: _Little Wanderers._ Ginn & Co. 30 cents.

Alice Lounsberry: _The Garden Book for Young People._ Stokes. $1.50.

Gertrude Stone: _Trees in Prose and Poetry._ Ginn & Co. 45 cents.

COMPARATIVE LESSON ON VARIETIES OF WINTER APPLES

KING, BALDWIN, NORTHERN SPY

Discuss the names, keeping and cooking qualities of the apples, and bearing qualities of the trees.

Provide each member of the cla.s.s with a typical representative of each of the above varieties of apples.

Compare the three apples as to size, form, colour--including marks; hardness, length, and thickness of stem; depth of cavity at the stem end; depth and shape of the cavity at the calyx end.

Split each apple from stem to calyx and compare as to the thickness and toughness of the skin, the colour of the flesh, the size of the core, taste and juiciness of the flesh.

_To the teacher._--All three are apples of fair size, the Baldwin being on the average the smallest of the three. All three are roundish, but the King is somewhat oval-round, and the Spy, conical-round. The Baldwin has a yellowish skin with crimson and red splashes dotted with russet spots. The King is reddish, shading to dark crimson. The Spy has a yellowish-green skin sprinkled with pink and striped with red.

The beautiful colours make all these apples very popular in the markets of American cities and in those of the British Isles; but the soft and easily damaged skin of the Spy makes it the least desirable as an apple for export.

All keep well and in cool cellars remain in good condition until April.

They may be kept much longer in cold storage chambers, where the temperature is uniformly near the freezing point of the apple.

The Baldwin apple tree is reasonably hardy within the ordinary range for apple trees, and its yield is a satisfactory average. The King apple tree is not a hardy tree, nor is it a satisfactory bearer except in the best apple districts. The Spy is a fairly hardy tree and thrives and yields well throughout a wide range; but it does not begin to bear until it is about fifteen years old.

A comparative lesson may also be based on selected varieties of autumn apples, such as Fameuse, McIntosh Red, Wealthy, Gravenstein, and St.

Lawrence.

CODLING MOTH

Begin the study of the codling moth in August by examining wormy apples.

Find out, by asking the pupils, which orchards of the locality had been sprayed in the spring.

Ask the pupils to count out at random one hundred apples and to select from these the number that are wormy. What percentage of the apples are wormy? Compare the percentage of wormy apples in unsprayed, with that in sprayed, orchards. The results will afford evidence of the benefit of spraying.

Find out, if possible, the dates on which, and the conditions under which, the spraying of the orchards with the least number of wormy apples was done.

Ask the pupils to bring to the school-room a number of wormy apples.

Have the pupils cut these open and note the nature and position of the hole, or burrow, and the amount of damage done to the apples.

Have the pupils observe the larva and note the size, colour, shape, and number of legs.

_To the teacher._--The apple maggot is a less common insect larva and may be distinguished from the larva of the codling moth by the fact that the former has no legs and has the habit of burrowing in all directions through the pulp of the apple, while the larva of the codling moth works almost entirely in the core.

The coc.o.o.n and pupa phase of this insect may be obtained by keeping the wormy apples in a box containing loose paper on which the coc.o.o.ns will be placed, or by searching under the bark scales of apple trees in October.

Describe the coc.o.o.ns. Open some of them and describe the contents. Keep the remaining coc.o.o.ns in a box or vivarium in a cool place during the winter.

What birds are seen tapping at the bark scales of the apple trees during winter? Examine the bark scales when a downy woodp.e.c.k.e.r has been at work and note that the coc.o.o.ns have been destroyed.

Should we encourage the visits of woodp.e.c.k.e.rs to the orchards?

By hanging up a beef bone in the orchard, various birds, including woodp.e.c.k.e.rs, will be induced to visit and perhaps to make their homes in the orchard.

REFERENCES

_Common Insects Affecting Fruit Trees, Bulletin No. 158_, Department of Agriculture, Parliament Buildings, Toronto.

_Bulletins Nos. 158 and 171_, Ontario Department of Agriculture, deal with many insect pests and their remedies.

In May look for the adult moths as they emerge from the coc.o.o.ns. Observe the colour, size, shape, and the bright copper-coloured horse-shoe on the front wing--the "brand" of the codling moth.

Examine the little apples when the blossoms are falling. Note the tiny, flat, oval-shaped egg at various places on the surfaces of the apples and a few days later the tiny worm which emerges from the egg. This soon eats its way into the apple, entering usually at the calyx end. If spraying is done after the petals have fallen and just before the calyx end closes up, a drop of poison is inclosed, and when the larva enters it and begins eating its way into the apple, it gets the poison.

SOME COMMON ANIMAL FORMS

Brief lessons should be given on some of the lower members of the animal kingdom, for the purpose of broadening the interests of the pupils. The following are suggested as types: snail, spider, freshwater mussel (clam), crayfish (crab), centiped, milliped, salamander, and wood-louse.

These are common animal forms, most of which are frequently seen by the pupils, but seldom are their interesting life habits or their places in the animal kingdom recognized. The salamander is to many pupils a lizard of the most poisonous kind; centipeds and millipeds are worms, and they do not recognize that the clam is an animal with sensibilities and instincts.

REFERENCES

Kellogg: _Elementary Zoology_

Silc.o.x and Stevenson: _Modern Nature Study_

CENTIPEDS AND MILLIPEDS

Under stones and sticks in moist soil are to be found two worm-like forms, both having many legs.

One of these animals is flat, about an inch long, brown in colour, and provided with a pair of long feelers. On each division of the body is a single pair of legs. This is the _centiped_. The other animal is more cylindrical in shape and has two pairs of legs on each division of the body. Its colour is a darker brown than that of the centiped, and it has a habit of coiling into a spiral shape, when disturbed, so that the soft under surface is concealed. This is the _milliped_. Both of these animals are quite harmless and feed on decaying vegetable matter. They stand midway between worms and insects in forms and habits.

A brief observation lesson on each animal, involving their movements and the structural features named above, will enable the pupils to identify them and to appreciate their position in the animal kingdom.

SALAMANDERS, OR NEWTS

Some forms of these are found in water, as in streams, ponds, and ditches, while other forms are found on land, where they hide under stones and sticks. They are commonly mistaken for lizards, which they closely resemble in shape; but the two animals may be distinguished by the fact that the surface of the body of a salamander is smooth, while that of a lizard is covered with scales.

The small red or copper-coloured newts are the most common in Ontario and are frequently found on roads after heavy rains. The tiger salamanders are larger than the red newts and are marked with orange and black spots, hence the name "tiger". Many people believe this species to be especially venomous, while in reality it is quite harmless and, like the other salamanders, is useful for destroying insects and small snails, which form the greater part of its food.

_To the teacher._--The superst.i.tion of the salamander's power to extinguish a fire into which it is thrown still exists. The early life of the salamander is spent in water, the young form being very much like a tadpole. The salamanders are close relatives of the frogs and toads and may be kept in a jar or vivarium in wet moss or gra.s.s. The pupils should learn to recognize the animals and should be instructed as to their habits.

SPIDERS

~Problems in observation.~--In how many places can you find spiders' webs?

How many forms of spiders' webs can you find? Are the many webs that are found on the meadow gra.s.s in the dewy mornings the homes of spiders? If so, describe where the spiders live. (At the bottom of tunnels that run into the ground.)