Man as an agent in the dispersal of seeds should be made a topic for discussion.
Obtain, through the pupils, samples of seed-grain, clover seed, timothy seed, turnip seed, etc. Ask the pupils to examine these and count the number of weed seeds found in each.
The results will reveal a very common way in which the seeds of noxious weeds are introduced.
Describe the introduction from Europe to the wheat-fields of the Prairie Provinces of such weeds as Russian thistle, false-flax, French-weed. The seeds of these weeds were carried in seed-grain, fodder for animals, and also in the hay and straw used by the immigrants as packing for their household goods.
Careful farmers will not allow thrashing-machines, seed drills, fanning-mills, etc., to come from farms infested with noxious weeds to do work upon their farms, nor will they buy manure, straw, or hay that was produced on dirty farms.
THE SUGAR MAPLE
FIELD EXERCISES
Select a convenient sugar maple as a type. Ask the pupils to observe and to describe the height of the tree, the height of the trunk below the branches, the shape and size of the crown, the diameter of the trunk, the colour of the bark, the markings on the bark, the number and direction of the branches, and the density of the foliage. Compare the density of the foliage with that of other kinds of trees. Require the pupils to make a crayon drawing of the tree.
Examine the crop of grain produced near a shade tree. Compare the crop on the north side of the tree with that on the south side. Account for the difference.
Is the crop around the tree inferior to that in the rest of the field?