Popular Science Monthly/Volume 86/January 1915/The Cinchona Botanical Station II

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1581054Popular Science Monthly Volume 86 January 1915 — The Cinchona Botanical Station II1915Duncan S. Johnson

THE CINCHONA BOTANICAL STATION. II

By Professor DUNCAN S. JOHNSON,

THE JOHNS HOPKINS UNIVERSITY

The Native Vegetation of the Cinchona Region

The native flora of Cinchona Hill is a varied and interesting one. Being south of the mountains, and on a sharp ridge with perfect drainage, the soil often gets quite dry. Especially is this true of the small pockets of humus in the rock clefts occupied by the numerous rock xerophytes, and of that gathered on the limbs of trees or held among the clustered roots of epiphytic orchids. We find here, therefore, many species characteristic of these xerophytic habitats. There are century plants, leathery-leafed terns, aroids, bromeliads, orchids and Peperomias growing in the clefts of the rocks and on the branches of trees and shrubs. Climbing or creeping ferns, aroids, orchids, milkweeds and cacti run over the ledges and larger plants. On the branches of the juniper and Dodonaea, of the thick-leafed Vaccinium, and even of the nearly leafless Baccharis on the dry hillsides, many species of leafy or

Cliff with Xerophytic Plants. A century plant in its native home.

Two Cinchona Trees.

cactus-like mistletoes are thickly scattered. These half parasites win out in the struggle against drouth by allowing other plants to find water for them.

In the moist hollows, or on northern slopes of Cinchona Hill, many plants of temperate zones have established themselves, being brought there, presumably, with vegetable seeds imported from England. Clover, dandelion, dock, mullein, plantain and yarrow grow beside the trail. Wild strawberries bloom and ripen throughout the year. Side by side with these old acquaintances are thick clumps of the spicy-flowered wild ginger, and, towering over them are orchids and begonias as high as the head, canes and bamboos twenty feet tall, gray-barked, red-leafed cinchona trees and brilliant-flowered Melastomaceous shrubs. The lantana, Cherokee rose, passion flower, prickly-leafed ferns and the wiry-stemmed grass Chusquaea clamber over every thicket. Ferns abound everywhere, in sun or shade, and in moist or dry situations. Along one trail from Cinchona, toward the mountains, a hundred species of ferns may be seen in an hour's walk without leaving the path. Professor Underwood estimated that four fifths of the 500 species native to Jamaica occur within a day's ride of Cinchona. We may well note, by way of comparison, that but one hundred and fifteen species are given in Gray's Manual for the whole northeastern United States.

Lower down, for we have been speaking hitherto of the levels near that of the Cinchona residence, the vegetation on this south side of the Blue Mountains becomes more luxuriant in the valleys and more xerophytic on the ridges. In the former the trees, such as Alchornea latifolia and Prunuis occidentalis grow to a height of 60 or 70 feet, and lianes, such as Mauirandia, Begonia, Rhynchosia and Bidens climb to their tops, while a new series of ferns and shrubs make up the undergrowth. On the ridges also the plants have a different aspect. There are new species, to be sure, but even the same species, e. g., certain ferns.

Edge of Forest. Polypodium, Chusquaca (at x) and other climbers.

that in the damper regions above may be two feet or more in height, are reduced, on the exposed rocks of the hotter lowlands, to pigmies of but two or three inches when mature.

On hundreds of acres of the rocky hillsides for 2,000 feet below Cinchona is raised the Blue Mountain coffee, which Jamaicans, and the London coffee tasters, say is the finest coffee in the world. The coffee beans, the seeds of a small Abyssian tree related to Cinchona, are borne, two together, in each of the bright red, cherry-like fruits. The trees are grown on the steep, rocky ground, with oranges or bananas scattered in

Coffee Planter's Home with Cement Drying Floor (Barbecue). Pulping mill and windrows of drying coffee at left.

for shade. They are cultivated entirely by hand and are pruned down to five or six feet for convenience in picking the berries. The coffee beans are freed from pulp, shelled out of the parchment after drying, winnowed and polished, sometimes by gasoline engines, but usually by water power from the mountain streams. The beans are then sorted to sizes by screens, culled over by hand, and sent to Kingston, 15 or 20 miles away, on pack mules. Other parts of the cleared ground below Cinchona are planted with vegetables by the negro natives. These temporary tenants clear the land, raise potatoes, cabbages, scallions (onions), beets, yams and coco root, for three years on it and leave it with a good set of young coffee trees in payment for the lease.

Two miles north of Cinchona and at the same level, 5,000 feet, there is a notch in the main mountain range known as Morce's Gap. As one passes northward through this gap one sees the aspect of the vegetation change with surprising suddenness from that characteristic of the immediate neighborhood of Cinchona. Here, on the windward side of the mountains, everything reeks with moisture, for during most of the year clouds or mist drift through these gaps continuously from the cool north side of the mountains. Rain falls almost daily for much of the year,

Berries and Flowers of Coffee.

and even when it is not raining the clouds form and float through these dark forests. Ferns are in their glory here in this dense montane rain forest. There are scores of tree ferns, of half a dozen species, with stems three to six inches thick and ten to thirty feet high. Their straight slender trunks contrast strikingly with the forked, twisted branches of the Podocarpus, prune and other trees among which they are scattered. Most of the trees on some half-acre patches are tree ferns of the genera Alsophila or Cyathea. Their beautiful umbrella-like crowns are seen best from a hillside above them, or when their delicate plumes are outlined against the sky. Under these ferns and the other

Tree Ferns at Bottom of a Valley.

trees are Marattias and Dunaeas, with Nephrodiums and Aspleniums of many varieties. Gleichnias and Davallias fringe the trails, while Lomarias, Trichomanes and Polypodiums twine about the tree trunks and epiphytic Acrostichums, Elaphoglossums, Polypodiums and Lycopodiums settle on the stems or branches of Cyathea and other trees. The beautifully delicate Hymenophyllum and Trichomanes form thick carpets over damp cliffs, and over living or dead trunks. Even high up on trunks or branches they may form dense tufts or lace-like curtains. These filmy ferns here take the place, in part, of the mosses of our northern forests, on soil, rock and trunk. But the mosses themselves are here also to war with their competitors for standing ground and sunlight. Mingled with Collema and other lichens, the mosses form spongy tufts over trunks and branches clear to the tops of the trees. Other species hang from the trees and lianes in festoons a yard or two in length.

The seed plants also of this rain forest show the same diversity of habit. There are dozens of climbers and twiners, such as Bidens, Marcgravia, Sciadophyllum and Rhynchosia, which cling to the trunks of the larger trees and so make their way up to the light. The Marcgravia is especially interesting from its possession of honey cups, which tempt the humming-birds that accomplish the pollination of its simple, inconspicuous flowers. Scores of bromeliads and orchids, as well as the ferns mentioned above, have become air plants, entirely without any connection with the ground. These epiphytes collect water and the solid food needed either from material falling into their cup-like leaf clusters, or absorb them as they drip down over the bark of the supporting tree. Indeed, trees of some size may find the necessary soil and water in the turfs of smaller air plants and the débris accumulated by them, even forty or fifty feet from the ground on the limbs of a big Podocarpus. The very leaves of trees, shrubs and of the more persistent herbaceous plants may become covered with epiphytic lichens and liverworts. In all these cases the air plants are not parasites, but simply use the trunk, branch or leaf as a standing place in which adequate light is available. In the lowlands we saw certain of these air plants actually flourishing on telephone wires.

If we go northward from Morce's Gap and down 2,000 feet into the

Marattia on a Hill Side.
Podocarpus Tree and Tree Fern beset with Epiphytic Bromeliads and Ferns.

Mabess Valley, we find a region of much higher temperature and of still more constant rainfall. Here the vegetation becomes even more luxuriant, and, though made up of similar vegetational types, it includes many new species of ferns, like Rhipidopteris peltata and Lygodium volubile. There are high-perched tufts of brilliant Pitcairnias on the ledges. Carina and its relative Heliconia, with the thatch palm, Geonoma, grow along the stream, while clumps of the beautiful Rubiaceous shrub, Cephaelis punicea, are scattered on the slopes higher up.

On climbing the high peaks near Cinchona, such as John Crow, on the west, or Sir John and Blue Mountain Peak, on the east, one finds still other interesting and novel vegetational features to enlist the attention. The trees on the ridges are bent and twisted. The more or less horizontal branches are interlaced in a way that makes following the "trail" a rather perplexing combination of climbing over, creeping beneath and squeezing between the dripping, moss-covered trunks and branches. These experiences are varied, however, on other parts of the ascent, by slipping down, while attempting to creep up, the steep, grass or fern-covered slope of a particularly lubricous clay. New forms, appear with increasing altitude, many of them rarities. The tops of these peaks are occupied by low, gnarled trees of Podocarpus Urbanii, and by head-high, mistleto-covered bushes of Vaccinium meridionale and Clethra alexandri, or by wide stretches of the fern Gleichenia or the grass Danthonia shrevei. The northern slopes of these Blue Mountains, down to the 2,000-foot level, are practically unexplored territory, with no trails, except that skirting the Mabess Valley.

All the points here mentioned, except Blue Mountain Peak, are

Tree Fern whose Trunk is covered with Epiphytes and Climbers.

within four or five hours' walk from Cinchona, and they thus offer the investigator very diverse specific and vegetational types within easy reach of the station. Any one of them also could be made a substation at which an investigator resident at Cinchona could carry on physiological

Swaying Tufts of Mosses hanging from Branches above Young Tree Ferns.

or climatological work. Indeed, the variety of conditions available is far greater than has been indicated. Within half a day's ride from Cinchona a botanist can reach the steaming tropical lowlands of the north side of the island, the warm valleys and dry ridges of the southern slopes, and even the hot plains, coastal deserts, mangrove swamps and coral reefs of the south shore.

Advantages of Cinchona as a Tropical Station

It will make clear the unusual fitness of Cinchona as a tropical station if we here summarize its various advantages of location, surroundings, equipment and accessibility.

Hanging Garden. Twenty-five species of ferns and seed plants growing upon the limb of a tree forty feet above the ground. At left are the erect stems of two epiphytics.


Epiphytic Lichens and Liverworts on Living Leaves of Shrubs and Trees.

Cacti and Giant Milkweed, Culotropis, on Desert Southern Seacoast.
Coconaut and Mangroves (Mature Ones in Background) on Swampy South Coast of Jamaica.

In the first place it has that supremely important requisite, a primeval forest. There are scores of square miles of this within easy reach of Cinchona. It is only in such a forest that the extreme complexity attainable in a plant formation can be seen. Moreover, Cinchona is located in a botanical garden where scores of exotics are established, and where greenhouses, propagating grounds and helpers of some experience are available for collecting and growing material.

Secondly, because of the small size and irregular topography of the island of Jamaica, areas furnishing many varieties of conditions, from mountain peaks to coral reefs, can be readily reached from Cinchona. For example, there are about Cinchona 25 square miles of mountainous

A Leafless Silk Cotton Tree bearing Numerous Fruits. All the foliage in the crown of this tree belongs to the thousands of epiphytes on its branches.

country above the 5,000 foot level, and 140 square miles above 3,000 feet. There are also within reach river bottoms and sandy or rocky, desert or swampy sea coasts.

Thirdly, there are already two botanical gardens established in the lowlands where they can be used as substations for the study of problems concerning plants of these regions. One of these, Castleton, is in a damp region at 500 feet elevation, where it has a rainfall of 140 inches and a mean temperature of 75 degrees. The collection of plants here includes many ferns, cycads and screw pines, over a hundred species of palms, fine examples of Ficus and numerous other dicotyledonous tropical
Entrance to Castleton Gardens. The palm above the gate (Attalca) has leaves ten yards long and two yards wide.

trees. The other garden, which is at Hope, is on the dry Liguania plain, slightly higher than Castleton, but with a mean temperature of 76 degrees, and a rainfall of only 61 inches. At Hope Gardens there are an excellent library, laboratory accommodations, and very interesting collections of living orchids, cacti and economic tropical plants. For one wishing to study the marine algae it would be readily possible to secure rooms or a building on the water front, at Kingston or Port Royal. It is probable also that a marine zoological station will soon be established at Montego Bay, and will be available for botanists wishing to study the algae of that region.

A fourth very important advantage of Cinchona is that it is located in the healthy highlands where the climate is stimulating for workers from the temperate zones; where the water supply is pure, and where malaria and enteric troubles are not to be feared. Professor Goebel, after having much experience in tropical travel, wrote, when advising the Tropical Laboratory Commission referred to above:

If at all possible the main station should be in the highlands, with a subsidiary station in the lowlands or on the seashore for the study of the algae, and the vegetation of tropical plains.

It means much also to workers of normal social instincts, especially to those who are to settle down at such a station for some months, to be able to work in pleasant surroundings, and to have interesting neighbors outside the laboratory, when there may be few fellow-workers within. At Cinchona, with its comfortable house and delightful garden, with its splendid views of mountain and valley, of Kingston Harbor with its gliding ships and twinkling lights, the worker is assured of restful diversion for his leisure hours. Nor need he entirely lack pleasant association with Ins fellow man, though his nearest neighbors, coffee planters, are several miles away. The planter leads an active outdoor life in the invigorating climate of the hills, but he finds time for sociability, and at four o'clock he is indoors for tea. This custom is clung to as faithfully here as on the banks of the Thames. This is the time of day when one's next door neighbor, from two or three, or even from five or six miles away, rides over for tea, for a chat over the news of the Hills, or perhaps for a game of tennis. The temporary tenant of Cinchona may

Corner of Castleton Garden, with Cycads, Palms and Araucarias.

always feel sure of a welcome at these neighborly gatherings. In fact he must needs be careful, if his collecting trip should take him across a plantation at tea time, not to be captured by the proprietor. Within the planter's home the visitor will find many of the comforts and some of the luxuries of modern life. There are books, magazines and newspapers that keep the planter in touch with the outside world. Often there is a piano, brought ten or fifteen miles over the mountain trails on the shoulders of negroes. Members of the family who play the instrument may often show good evidence of a training gained in England or on the Continent.

Finally, it is a matter of no small concern that a permanent tropical station for British and American workers, should be located in an English-speaking country, with a stable government and reliable sanitary control, and in one readily reached from the United States and Europe. Jamaica has the advantage of not being subject to revolutionary upheavals. Its quarantine against the entrance of tropical disease is strictly maintained, and there is a good postal service. There are 2,000 miles of good roads in the lowlands, and two of these already reach within five or six miles of Cinchona. Similar roads are soon to replace other of the well-kept bridle trails already built in the Hills. Thus by railroads, roads and bridle paths all parts of Jamaica are accessible from Cinchona. The island itself can be reached from the United States in four or five days, from five Atlantic ports, while the voyage from England takes but ten or twelve days.

We are to have available then a laboratory, readily accessible, and in a very favorable location, of which Professor D. H. Campbell, who has studied tropical vegetation in many lands, writes:

I can think of no place where the fern vegetation is so rich and where other types of tropical vegetation are more accessible.

We believe the opportunity here offered will be more and more frequently embraced by botanists, and that this laboratory in the western tropics will doubtless, as was suggested by Goebel, "be of the very greatest importance to the science, and will give a strong impulse to the study of botany in America." Jamaica will then be honored among men of science for the maintenance of this laboratory, as Holland has been for the support of the famous station at Buitenzorg.

The Harpswell Laboratory,
August, 1914.