7th.—Mr. Lumley and my uncle have been studying Dr. Richardson’s remarks on the climate of the Hudson’s Bay countries, and I have noted for you all I could understand.
In the neighbourhood of Fort Enterprise, lat. 64° N. the white spruce advances nearer the northern limit than any other pine. The largest of those trees were between eight and nine feet in circumference. The elm, ash, sugar-maple, and arbor-vitæ extend to nearly the same latitude.
Oak and beech terminate about lat. 50°. The balsam poplar sends straggling trees as far north as lat. 63°, and the aspen grows in pretty large clumps a degree farther north, beyond which it was not seen. The balsam poplar forms a large proportion of the drift timber observed on the shores of the Arctic Sea, and is supposed to come principally from MᶜKenzie river.
Fort Enterprise was supposed to be elevated about 800 feet above the Arctic Sea, and the banks of the river on which it was built are ornamented with groves of the white spruce tree. On each side of the river, an irregular marshy plain extends to ranges of unconnected hills, at the base of which there is commonly a thin stratum of mountain peat. The bottom of the valleys is generally occupied by lakes of a considerable depth, which are entirely land-locked, and communicate with each other only when flooded by the melting snow. The sides of the hills, and all the drier spots of the valley, are clothed with a beautiful carpet of the lichens, which form the favourite food of the reindeer; and some shrubs, such as the great bilberry, the marsh ledum, some of the willow tribe, and different species of andromeda, arbutus, and the kalmia glauca, frequently enliven the scene.
In sheltered situations, where the peat is deeper than usual, a few starved larch and black spruce are scattered. There are also thin clumps of the paper birch on the borders of the rapids, as well as of the white spruce, which thrives better there than any other tree; but all are of slow and stunted growth. Of the spruce cut down at Fort Enterprise, the increase seemed to have been in general at the rate of four rings, or years, to one inch; and though the house which the travellers built there was only 24 feet wide; it was with difficulty they obtained half a dozen beams of sufficient length, the trees tapered so much.
It appears by Dr. Richardson’s tables, that up to the 20th of June, 1821, there was no appearance of vegetation among the flower-bearing plants, except the gradual opening of the willow catkins. Early in June, the first, or female band of reindeer passed to the northward of lat. 65°; their progress seemed to be regulated by the uncovering of the lichens. When the thaw is much farther advanced, the lichens become too tender and pulpy, and the deer resort to the swamps to feed upon the grass, or rather hay, which having been frozen up in the preceding autumn, retains its sap and nutritive qualities, when the snow melts from around it in spring. In a few days, however, the stalks become dry, and the seeds are shed; but the deer by that time have reached the sea-coast, where other plants supply them with food, which, however, are not so fattening as the lichens.
On Midsummer-day the dwarf birch opened its buds; a fortnight afterwards the ice on the larger lakes broke up, and several plants flowered. But on the 5th of September a storm set in, which clothed all the country with snow for the winter; and in the beginning of October the party again walked over the lakes which they had crossed on the ice in the middle of June; an interval of only 116 days.
The sap of the trees and shrubs freezes there in winter; and the wood becomes so hard that the chips produced by an axe flew off more like splinters of stone than of wood.
In all those dreary districts there are no traces of the influence of man over the appearance of the vegetable kingdom. Cultivation is entirely confined to a few small gardens at the fur-posts; and the only mode in which the arts and customs of the natives affect the vegetable kingdom, is by their setting fire to the forests. These fires spread rapidly in summer, and are only extinguished by heavy rains. Years elapse before anything grows in the places thus laid waste. The branchless trunks of the burnt trees are in a season or two stripped of their bark and bleached, if not sooner thrown down by the wind. The surface of the ground in time acquires a little verdure from a few mosses and lichens; other vegetables take root; and, at last, the place where a pine forest had been, is occupied by dense thickets of slender aspens. The growth of this tree,—instead of a renewal of the pine forest, which might have been expected,—is a curious circumstance, and can be attributed only to its winged seeds favouring their dispersion.
I hope what I have written will amuse you, as in your last letter you wished to hear something of the discoveries made by Captain Franklin’s party.