Nature Notes banner
GRAND CANYON NATURE NOTES
July 1934Volume 9, Number 4


CANADIAN ZONE PLANTS on the SOUTH RIM of GRAND CANYON

By Junior Naturalist Donald Edward McHenry

One of the features for which the Grand Canyon is noted is the variety of climatic conditions represented in its walls. Such climatic differences are easily recognized when one compares the North and South Rims. On the North Rim, where the Canadian type prevails, such trees as Blue Spruce (1), Engelmann Spruce (2), Alpine Fir (3), White Fir (4), Douglas Fir (5) and Quaking Aspen (6) are characteristic. On the South Rim where the altitude is from 1,000 to 2,000 feet lower, and the climate is warmer and drier, one does not expect to see these trees. Here the scrubby Pinyon Pine-Juniper forest is quite characteristic. Tall Western Yellow Pines and scrub oaks also cover large areas.

Here and there on the south side of Grand Canyon one will discover isolated pockets of Canadian Zone plants tucked away in alcoves just beneath the plateau where the graceful forms of the Douglas Fir and White Fir are found rising majestically almost against the very cliffs. In these north-facing coves they are protected against the long hours of the hot, direct rays of a merciless summer sun and against the hot, moisture-absorbing winds blowing off the vast arid regions to the southwest. Because the climatic condition in these places is cooler and more moist, plants of the Canadian Zone thrive at an elevation over a thousand feet lower than that of their normal environment and, strangely enough, actually below the plateau which is characterized by a hotter climatic condition.

(1) Picea pungens
(2) Picea engelmannii
(3) Abies lasiocarpa
(4) Abies concolor
(5) Pseudotsuga taxifolia
(6) Populus tremuloidesaurea

So distinctly confined to these restricted areas are these Canadian outlaws that they are almost never seen above the South Rim. There is, nevertheless, a noteworthy exception to this rule. Along the rim about half a mile east from the site of the old Grandview Hotel, near Grandview Point, the writer discovered quite an advanced detachment of Douglas Fir seedlings extending for several hundred yards back from the edge. These ranged in age from about two to ten years. Their locality was favored in being a somewhat more protected and lower spot than the region immediately surrounding. Down this trough drains the cooler, heavier air before it spills over into the ravine below. Dick Gilliland, an 'old-timer' at Grand Canyon, reports a well developed, mature tree of Douglas Fir in the Western Yellow Pine forest just about a mile south of Grandview Point.

That Douglas Fir and White Fir grow in sheltered groves under the South Rim has long been recognized as normal, yet as far as the writer knows, no spruce trees are to be found anywhere along the rim. But then he has had the opinion that Quaking Aspen were restricted to the North Rim at Grand Canyon until recently Dick Gilliland led him to a shimmering grove of these trees tucked down in the secret recesses of an all but forgotten gulch. This delightful group included possibly two hundred trees both young and old. It was located on the rim about three-quarters of a mile east of the site of the old Grandview Hotel at the mouth of a ravine. This ravine heads in the neighborhood of the tank seen at the foot of Buggeln Hill, looking north just off the east rim drive to Desert View. The spring thaws and summer down-pours wedge their water between the narrow, precipitous walls of this diminutive valley. These incidental streams race madly through the Aspen grove, only to dash recklessly over a ledge just beyond, as an ephemeral water fall, disappearing in the foam among the boulders 200 feet below the canyon rim.

This elfin glade, with the fairy green of the quivering Aspen hidden in the bottom of a ravine, evidently was the secluded bower of lovers in the days of the Grandview Hotel. A Cupid's dart through a heart, together with the date, "August 13, 1891" was cut with deep black gashes into the chalk-white bark of one sturdy veteran. Quite evidently this was done in a day long before there were any Park rangers to discourage even lovers from marring the native beauty of nature's wonderland.

<<< Previous
> Cover <
Next >>>

vol9-4d.htm
14-Oct-2011