Page:Popular Science Monthly Volume 50.djvu/586

From Wikisource
Jump to navigation Jump to search
This page has been proofread, but needs to be validated.
568
POPULAR SCIENCE MONTHLY.

except the snowy owl, and one unrecorded species was seen. The flora is remarkably uniform, and the influence of height has less effect upon it than situation and season. The species found on the mountain summits in the middle of the summer were the same as those observed on the coast at the beginning of spring. As the season advanced, the species first found in flower on the lowlands and in sheltered valleys were succeeded by another set; but at any time it was only necessary to seek exposed and barren positions, or to climb above the snow line, to find the first flora still in flower. Spitzbergen offered better opportunities for geological than for zoölogical or botanical research. One of the main temptations it offers the geologist is a magnificent opportunity for the study of glacial action; for there, says Mr. J. W. Gregory, of the expedition, we may see marine and land ice working side by side. The inland glaciers are very different from those of Switzerland, especially in having no névé fields. All the snow that falls on the collecting ground at the head of the glacier turns to ice on the spot. Cases of the formation of typical bowlder clay by land ice were easily found; so, likewise, were instances of the uplift of material through ice. The glaciation of Spitzbergen was solely due to a local ice action. No evidence was found of a great polar ice cap.

Care of the Lawn.—An interesting little article in Garden and Forest on lawn and grass infesting insects contains some valuable information for the suburban householder. Land cultivated in one kind of crop for many years successively tends to attract all the different kinds of insects that feed upon it. In some localities where onions were grown in times past with excellent results the onion maggots now make it impossible to raise a crop. In many parts of New York State wheat culture had to be abandoned for a time because of the ravages of the Hessian fly. Farmers have long known that after land has been in pasture for a few years, or has been mowed, the grass "runs out." They accept this fact, and act upon it without much questioning as to just what this running out consists of. In many cases it is simply because the land has become so thoroughly infested with grass-feeding insects that the roots are no longer able to support a growth. Insects are not confined to farms or farm lands; they occur wherever plants are grown in cities and villages, and are troublesome in the back yard, in the kitchen garden, to the shade trees, and even to the little patch of lawn in front of the house. The more extensive the lawn and, in a general way, the better kept it is, the more attractive it is to insects. Insects of almost all orders are found in grass lands, and, as there are few grass plots in which there is not also some clover, insects infesting this plant are also more or less abundant. It is always a matter of interest to determine what is causing the injury, but, after all, the important question is, What can we do to check it? On lawns, where the object is to keep the grass as long a time as possible, one of the simplest measures is frequent cutting and rolling. This has a tendency to drive off the lepidopterous insects that may be among the grass, and to prevent the laying of eggs. The grass should be always kept well fed; but no barnyard manure should be used: all insects do very much better in a soil containing much vegetable matter, and are least at home where mineral fertilizers are constantly used. Lawns should be fed almost entirely with mineral fertilizers, nitrate of soda being used to furnish the necessary nitrogen, and kainit or muriate to furnish the potash. The fertilizer should be applied just before a rain. Where land is badly infested and there is poultry about, it is a good plan to dig up the sod and turn the chickens in for a few days. They will, if the soil is turned over two or three times, pretty thoroughly dispose of the bugs. A kerosene emulsion is fatal to the insects and does not injure the plant roots.

The Advantage of Elective Courses.—The Hon. T. W. Higginson, referring in the recollections of his life which he is now publishing in the Atlantic Monthly to the time when he was secretary of the College Natural History Society at Harvard, observes that "in looking back on the various reports written by me for its meetings, it is interesting to see that this wholly voluntary work had a freshness and vigor beyond any which