The following is a somewhat abbreviated translation of a paper on the North American Forests, which has been' lately read by Sir Dietrich Brandis before the Natural History Society of Bonn. As the sources of his information, the writer refers to a number of recent publications on North American Forestry, the chief of which are "A report on the Forests of North America" by C. S. Sargent, Professor of Arboriculture in Harvard College, 1884, and Dr. Mayr's "die Waldungen von Nord Amerika" Munich, 1890. The first part of Sir D. Brandis' paper is occupied by some criticisms on Dr. Mayr's generalizations from his observations in America; and few men have such wide experience in observing forest vegetation as the former head of the Indian Forest Department and would be sooner able to detect a generalization from incomplete data. Dr. Mayr is the son of a State Forest Officer in Bavaria and after studying Forestry and Botany very thoroughly at Munich, he was in 1885 sent to North America by the Government of Bavaria, to observe, at different ages, in their native forests, certain important trees, experimental plantings of which have been from time to time made in Germany. After spending seven months on these researches and afterwards extending his tour through Japan, Java, Ceylon, and northern Hindustan, Dr Mayr returned to Germany in 1888, and was shortly afterwards appointed Professor of Forestry and Forest Botany at the College of Agriculture and Forestry at Tokio in Japan. This gave Dr. Mayr a second opportunity of visiting North America, and during these two visits, he twice traversed the country from East to West, and also journeyed from Canada to Florida, and from Vancouver's Island as far as Mexico. Besides Dr. Mayr's actual observations during his stay in North America, he has made use of the rich material found in Professor Sargent's work already referred to, and also of the Annual Reports of the United States Agricultural Department published since Der Wald in den Vereinigten Staaten von Nord Amerika, von Dr. D. Brandis, in Bonn, 1891. Sonder Abdruck aus den Verhandlungen desNaturhistorischen Vereins; 47 Jahrgang. 1877 in Washington, which give much information regarding the North American Forests. The Forest Bureau of the Ministry of Agriculture was founded in 1876, and Dr. Franklin Hough was the first chief. He was succeeded in 1886 by Berhard Fernow, a Prussian trained forester, who is still at the head of the United States Bureau of Forestry. Fernow, in 1889, published in French a short account (43 pages) of the Forests of North America, to accompany the Forest collections intended for the Paris Exhibition of 1889. Dr. Mayr treats of the demands of the more important North American trees as regards climate and soil, with a summary account of their anatomical structure and of the physical and technical qualities of the most important woods. He also gives lists of destructive fungi and insects which he observed on different species. The book has made a considerable stir in the United States, and some criticisms regarding the account of some of the fungi described by Dr. Mayr have already appeared in Garden and Forest, 1890, p. 627. We now come to the generalizations which Sir Dietrich Brandis has controverted. In Mayr's introductory chapter, entitled-General notes on the conditions of existence of Forests-we find the unsound statement that evergreen broad leaved forest (not coniferous) requires a higher winter temperature than deciduous forest; and, again, deciduous vegetation is always absent in tropical countries on account of the uniformity of the climate throughout the year. If Dr. Mayr had visited the forests in the very hot, damp countries of Burmah and India, he would have noted that deciduous broad leaved forests form the most important forest area of these countries. The teak and a number of allied trees lose their leaves from December to February, and the new foliage only appears in May or sometimes in April. Extensive tracts of deciduous forests without teak are also found in these countries. The evergreen broad leaved forest is only found in the dampest parts, on the ridges and slopes of the mountains exposed to winds from the sea, in damp valleys, or in deep and very moist soil. This distinction between deciduous and evergreen forest is of the greatest importance in Indian Forestry, as forest fires rage through the deciduous forests at the hottest period of the year whilst they only damage the fringes of the evergreen forests. The trees in the deciduous forests are leafless, but not on account of the cold, for although the temperature is lowest in January, yet March and April are frequently the hottest months in the region referred to. It is on account of the dry season that they are leafless; these facts are also given by Junghuhn in a work frequently quoted by Dr. Mayr about Java, where it is the teak forests in the eastern part of the island that lose their leaves annually in the driest months beginning with July, but become green again in March and April at the end of the rainy season. In India, it is the a degree of humidity and not the temperature which causes the broad leaved forest. In many valleys of the Yomah mountains in Pegu, the northern slopes are covered with evergreen forest, whilst the southern slopes bear the far more valuable deciduous forest, containing teak. In the same way the Ghât mountains on the Western coast of India, contain vast areas of valuable deciduous forests with teak at the foot and lower parts of the chain, where, in the absence of any shade, the heat is intense from January to May. In damp valleys, we may find the evergreen forest low down the hills, surrounded by deciduous forests, which extend higher up on the dry slopes and ridges and with the mass of evergreen forest in the cooler and damper atmosphere of the higher slopes up to the crest of the mountain chain. Coming over the ridge into a drier region, the deciduous forest re-appears, similar phenomena being found in India beyond the Ganges. It is hence clear that Dr. Mayr's statement on page 10 of his book, that deciduous forest is always wanting in tropical countries, is not at all true. Sir D. Brandis maintains that similar phenomena are found in other parts of the world besides Asia and cites cases in Brazil, Venezuela and tropical Africa, for which see Botanische Zeitung, 1876, p. 38. These deciduous tropical forests are termed by Drude in his new manual of Geographic Botany, p. 254, as tropische regengrüne Walder, tropical monsoon green Forests. America is much richer than Europe in forest trees, for, compared with our 52 genera and 158 species, Sergent's Catalogue for 1883 of forest trees of North America, exclusive of Mexico, includes 158 genera and 412 species of forest trees, only a few of which are, however, of commercial importance. According to Fernow these are about 30 to 40, of which only 10 or 12 are brought to the market to any great extent. Several new species have been discovered since 1883, and a good part of the northern forest tract near the Pacific is not yet thoroughly explored. Sergent's 412 species, including all species in British North America, given by him in another list, may be classified according to their Geographical distribution, as follows:Atlantic tract Species common to both ... ... ... ... ... ... Species of the middle tract of the Rocky Mountains and border regions Tropical species near the coast of Florida ... .. 176 The trees common to the Atlantic and Pacific tracts are as follows: a/ Picea alba Pyrus jambusifolia (resembling our Mountain Ash.) Do. longifolia Do. amygdaloides. Juniperus virginiana, extending from New Brunswick to If we omit the 74 tropical species, we get 338 species in Sir D. Brandis considers numerical comparisons as misleading, as different authors do not recognize the same trees as independent species and it is hard to distinguish always between shrubs and trees. It is moreover clear that we may consider North America as richer than Europe in Forest species. Brandis here states that a number of American forest genera existed in Europe in tertiary times, but have since disappeared. Hamamel's At present the following are known Gymnocladus Kamamehi, Liquidamber, Planera, Carya, Chamaecyparis, Taxodium Sequoia and Pinus, section Toda. The only genera of European trees not found in North America are Ceratonia, Laburnum, Olea, Syringa, Laurus, whilst many species common to both countries are now only found in Europe south of the Alps. 9 One might therefore suppose that north of the Alps they were extirpated during the glacial period, being still able to maintain themselves to the south of the Alps. These species at present are distinguished under different appellations, but Brandis considers the characters of difference not sufficient to separate them, as has been recently demonstrated by Fliche in the case of Ostrya virginica (1). The following are suggested as instances and it is noteworthy that all six are found throughout the Atlantic region from north to south. 1. Cercis Canadensis L. Siliquastrum L. of the Medi 2. 3. terranean region. = Diospyros virginiana L.-Lotus L., perhaps introduced Celtis Qccidentalis L-australis L. Mediterranean re- 4. Platanus Occidentalis L=Qripntalis L. Eastern Medi- 5. Ostrya virginica Willd-carpinifolia Scop. Medi- 6. Castanea Americana Mich=vulgaris Lam. Mediterranean Betula Populifera and B. papyrifera also greatly resemble (1) NOTE.-Sur les formes du genera Ostrya, Bulletin de la Société botanique Engler's "Evolution of the Vegetable Kingdom" gives much that is of interest in the evolution of the extra tropical Hemisphere, but many doubtful points must be cleared up before we can understand the connection between European and North American Forest flora. Dr. Mayr divides the forest flora of America into A extends from the Atlantic Ocean up to 95 degrees West longitude, and includes a small tract of tropical forest at the northern extremity of Florida, rich in many species common to the West Indies, but of little importance in forestry. This flora is really tropical as Mayr states, being carried to 25 degrees north latitude owing to the heat of the Gulf stream. Sergent terms it semi-tropical, similar outlying tropical vegetation is cited by Mayr in the Riukiu Islands in Japan, and by Brandis at the foot of the Eastern Himalaya in lat. 28 degrees with a very damp climate and protected against winds from the north. Bordering on this small region of tropical forest, extends along the coast of the Gulf of Mexico and the Atlantic Ocean up to lat. 36 degrees a wide strip of evergreen broad leaved forest, in which the dark green shining leaves of Magnolia grandiflora, several oaks, and the paler green of the north American laurel, Persea carolina, are striking features. Mayr describes the bright green arrow-like leaves, several yards long, of Tillandia usneides, whilst the space between the crowns of the trees and the soil is crowded with evergreen shrubs of all sizes. On raised sandy hills the pine forest of Florida and the adjacent states extends northward into Georgia, South and North Carolina to lat. 36 degrees and west to Alabama and Mississippi. The Southern Maritime Pine Belt (Sergent) extends far to the west of the Mississippi river. Pinus australis also named Pralustris is the most valuable of the several species here occurring on account of its splendid timber, and yield of turpentine. The reddish heart wood of this pine is used for furniture and cabinet-making throughout north America and exported in large quantities to Europe under the name of Pitch Pine. Quite another species, however, Pinus rigida, which is abundant in the northern Atlantic States, bears the name of Pitch Pine in America and is there almost exclusively used for fuel. The zeal for planting out this inferior species in Germany is probably due to a mistake in nomenclature. Pinus australis is a comparatively slow grower, whilst the Loblolly Pine, Pinus Toda and Pinus cubensis are of quicker growth and if the present absence of forest management continues, they will endanger Pinus australis which, owing to its fine durable timber, is in great demand. According to Fernow, the mean annual local Ja fa. |