FERNALD DESCRIBES GEOLOGICAL SURVEY

The following article which was written by M. L. Fernald '97, Fisher Professor of Natural History, is reprinted from the current issue of the Harvard Alumn Bulletin.

Years ago, when asked by an English solicitor at St. John's to tell him what there is in botany to interest a man, I explained certain of the inter-relations of botany and geology, only to receive the astounding reply: "Why, Sir, do you not realize that you are prying into the secrets of the Creator?" Again, when visiting my home-village in Maine, I was seriously upbraided by a former schoolmate for my apparent disloyalty to the United States, which seemed evident to him because I was working on scientific problems connected with foreign countries.

Newfoundland is Important

But, singularly enough, Newfoundland, lying at the extreme eastern angle of North America, presents some remarkable features in the natural distribution of its native plants which throw a vivid light upon the recent geological history, not only of that region, but also of areas on the continent and by extension, of Northern Europe as well.

Common Conception is Wrong

To the conventionally educated New Englander the conception of a recent continental ice-sheet is familiar. This is supposed to have originated in the southwestern section of the Labrador Peninsula and to have swept south to Nova Scotia. Cape Cod, Long Island, northern Pennsylvania, and the Ohio valley; and recent studies, especially by Antevs, indicate that the front of this sheet began to rot approximately 25,000 years ago. As a natural outgrowth of this everyday conception, we are inclined to infer that all the region south of the entire Labrador Peninsula was similarly crossed and denuded by the last or Wisconsin ice-sheet.

Ice Avoided Salt Water

In brief, we now have very conclusive evidence that the last continental ice-sheet (the Wisconsin) which originated on the Labrador Peninsula and pushed southward, did not cross the outer Gulf of St. Lawrence, the glacial ice having there, as elsewhere, a natural dislike for deep salt water. Nevertheless, in many parts of Newfoundland, Wisconsin-time saw small local sheets of ice on some mountain-slopes and on some of the open plains; and these local Wisconsin sheets did as effective work in Newfoundland as in New England.

Southern District was Denuded

For example, witness the photograph of a thoroughly scoured and denuded area of southern Newfoundland which was unquestionably crossed by very recent ice. Here (at Burgeo) the granitic hills are absolutely stripped of all soil and rotten rock-mantle, and the conspicuously striated ledges contain gourges which look as if they might have been hacked only yesterday by a sharp mattock or heavy chisel. In this region, too, great boulders as large as small houses are scattered irregularly over the hills, the boulders having fresh and undecayed surfaces.

Much Land Undisturbed

In most of Newfoundland, however, the hills and high tablelands are deeply carpeted with a mantle of angular frost-broken and lichen-crusted material; transported boulders are not seen, or are small and conspicuously weathered; and the cliffs have very high talus-slopes, such as that of Hannah's Head on the lower Humber. The largest area in which the surface mantle is undisturbed and the rock-walls covered with a rotted crust that has never been scraped off is on the western side of the island, embracing the Long Range of mountains and the adjacent foreland.

Area Invaded Long Ago

In parts of this area, especially along the valleys and on the lower slopes of the hills, there are obvious signs of recent glaciation, but in others the rare glacial striae and the few transported boulders present are so far obliterated or rotted away that Professor Coleman concludes these regions were invaded only at the very beginning of Pleistocene time (many hundreds of thousands of years ago). On some of the tablelands, to quote Coleman's words, "No signs of glaciation were seen above the edge of the escarpment at 970 feet (aneroid), and a walk of four or five miles inland over the rolling surface of the tableland reaching 1.908 feet (aneroid), showed only angular blocks of Archaean rock of local origin. No foreign boulders were found, and the conclusion was reached that the southern part of the Long Range had never been glaciated."

Plants have not Migrated

To the systematic botanist, this region, which has never been glaciated or was glaciated only during an early glacial advance, is dramatically interesting; for, as we are now learning to expect, in such regions there are hundreds of plants now living which are so conservative that they have never migrated into the adjacent regions recently covered by Wisconsin ice.

Characteristics Sharply Defined

The species which constitute this relic-flora must have lived right through the last glacial period where they are; and a study of the other regions of the Northern Hemisphere which were not invaded by the last ice-sheets has shown an exactly parallel situation. In these spots, then, we have relies of an ancient flora which in regions of very recent glaciation has been completely exterminated. From a purely evolutionary point of view, these old plants are particularly interesting because they are species with very sharply defined characteristics and are now so fixed in their fundamental characters that they show little, in any, variation.

250 Species Brought Back

During the past summer, aided by a grant from the Milton Fund for Research, I spent practically all of July and August and part of September hunting for more of these endemic and relic species on or near the Long Range of Newfoundland and, although it will take all winter to work out the results at the Gray Herbarium, it is safe to state that my party, including Mr. Bayard Long of the Philadelphia Academy of Sciences, and my former student. John M. Fogg, Jr., Ph.D. '29, brought back more than 250 such species, many of them hitherto quite unknown any-where in the world. These plants were excessively localized, growing as small colonies on mountain tablelands or crests or at lower levels on cliffs and gravelly barrens.

Country is Unmapped

The thrill of exploring a country which is practically unmapped, which the tourist has not invaded, is itself tremendous; but when, in following the bases of fantastically weathered slopes, such as those of Western Head, or ascending pathless mountain-ides by working one's way (always in the face of rock-slides) up the precipitous walls, as at Tucker's Head on Bonne Bay, one comes suddenly upon a plant occupying an area of only a few square rods and never before known to botanists, the excitement is intense.

Specimens are Pressed

These "thrillers" are so numerous in western Newfoundland that the field-botanist is always on the qui vive, and it is a rare and poor day when novel plants of great scientific interest are not brought in. Then follows a full day, or perhaps two days, indoors, putting the treasures into press and starting their proper drying, before another active day of field work can be undertaken. Often enough, after stretching every muscle and testing every nerve in the ticklish ascent and descent of successive cliffs, we reach home with our knee-joints so lame and stiff that no one utters a single word of complaint at the enforced inactivity of the succeeding day!

Approach Glacial Conditions

Although the highest tablelands and slopes of western Newfoundland have had no recent glacial cap, some of them are today not very far removed from a local glacial condition. Practically every summer, compact snowbanks lie on the northern-facing slopes; and it is evident that, by a very slight reduction of the mean annual temperature these snowfields would be transformed into alpine glaciers.

Snow Fields are Dangerous

Much of the joy of exploration in western Newfoundland consists in attempting to cross these snow-fields, a feat practically impossible unless one cuts steps in the icy masses; for although looking safe enough, these long-weathered snow-fields have a glassy surface, and it is easier to fall than to walk upon them. The photograph of my two companions at the lower edge of such a snow-field illustrates an experience which can be enjoyed on hundreds of slopes in late August after the melting days of summer are past.