Page:TheTreesOfGreatBritainAndIreland vol04B.djvu/357

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Alnus
947

ovate, 4 to 6 inches long, 3½ to 5 inches wide ; base broad and rounded or truncate, occasionally cuneate; apex acuminate or cuspidate; pubescent on both surfaces, glaucous or brownish beneath; with 9 to 12 pairs of nerves, each ending in a triangular serrated lobule; petiole an inch or more in length, The amount of pubescence on the branchlets, petioles, and leaves is variable; but the buds appear to be always densely pubescent. The cones are much larger than those of A. incana, attaining about ½ inch in length and 4 inch in diameter. A. tinctoria grows in Yezo, according to Sargent, on low slopes in rich moist ground, usually at some distance from the banks of streams, which are generally occupied by A. japonica. A. tinctoria attains in Japan 60 feet in height, and 6 feet in girth; and was collected by Elwes at Asahigawa in Yezo. It was formerly in cultivation at Coombe Wood, where it was probably raised from seed sent by Maries; but no specimens can now be found there; and the only one which we have seen in England is a tree at Aldenham,’ about 15 feet in height, which is reported to be growing vigorously. There are trees of A. tinctoria in the Arnold Arboretum, Massachusetts, which were raised from seed collected by Sargent in Japan in 1892.

The grey alder extends in Europe much farther to the northward than the common alder, its northern limit in Scandinavia being about lat. 70° 30’. In Finmark it reaches the mouth of the river Tana, and following the shore of the Arctic Sea, the northern limit extends throughout Russia along the Arctic Circle. Its distribution is divided into two areas, a northern one extending southward in the plains of Russia to the 55th N. parallel; and a southern area, which comprises the mountain ranges of the Carpathians, Alps, Jura, and Apennines, where the tree grows at high elevations in the mountains, and descends along the river valleys to lower altitudes, as along the Rhone, Isére, Dréme, Durance, and Var in France, and along the Rhine and its tributaries in Germany, and along the Danube in Austria. Its southern limit passes westwards from Russia through Transylvania to Banat and Servia; but the tree is not found in Croatia, Dalmatia, or Istria. In Italy it descends along the Apennines as far south as lat. 43° 40’, and grows as a rule between 4000 and 6000 feet, occasionally as low as 3000 feet. It ascends in the Erz mountains to 2100 feet, in the Swiss Alps and the Tyrol to 5000 feet, and in France thrives at 6000 feet altitude near Barcelonette and Briangon.

In Scandinavia the grey alder is common in the pine and spruce forests, usually occurring as underwood ; but in favourable situations near streams attaining a con- siderable size. There are many fine specimens in the beautiful natural park, close to Gefle on the Baltic. These trees, many of which are suckers from the roots of old trees that had been felled, are narrowly pyramidal in habit. The largest measured 75 feet in height and 5 feet in girth, In Denmark, Mr. Prytz of the forest service, who has measured trees 65 feet high and 7½ feet in girth, informed me that the wood had been tested, and clogs made of 4. zzcana had worn as well as those manu- factured from the common alder. I saw several trees in a beech forest near Nykjobing averaging 60 feet in height and 3 or 4 feet in girth, In Denmark it grows better on dry soil than the common alder.


1 At Aldenham, and in gardens on the Continent, this species is cultivated under the erroneous name, A. incana, var. hirsuta. Cf. Schneider, Laubholzkunde, i. 134 (1904).