The white ash is a native of the eastern half of North America as far as latitude 53. It occurs in mixed, broad-leaved forests, on alluvial deposits alongside rivers and streams, and in moist forest associations. In Europe, it tolerates floods of longer duration and more Water-logged soils than the common ash. It also grows on less fertile soils, and is not damaged by late spring frosts because its leaves unfold later.
The white ash reaches a height of 30 to 40 metres and the bark is more coarsely furrowed than that of the common ash. It also differs from the latter in having brown buds. The odd-pinnate leaves are composed of broader, ovate leaflets and the seeds are narrowly lanceolate, about one-half narrower than the tongue-shaped wings. The seed, unlike that of the common ash, germinates in the spring of the following year. As it grows no faster than the common ash and its wood is of poorer quality it is not cultivated in European forests, though it has some value as an ornamental specimen tree in parks and avenues, especially on the poorer soils.
The manna ash is a tree of south-eastern Europe, where it grows south of the Alps and Carpathians. It occurs in Spain and southern France, but the chief centre of its distribution is Italy and the Balkan Peninsula, where it is found on dry, sun- warmed slopes in oak forests. In the northern areas of its range, it occurs chiefly on limestone soils. In the mountains it may be found at elevations up to 1200 metres.
Pines from the lower, dry elevations of central Europe, on the other hand, have broad crowns to shade their site as much as possible. Similarly, mountain spruces growing at high elevations, or in cold valleys, have slender, narrow crowns.
The main reasons for the introduction of new trees from other regions or continents is for their fruit, to increase the yield of timber, or to enrich the assortment of ornamentals. The introduction of new plants dates from long ago; its beginnings can be traced to the cultured peoples of ancient times, who concentrated primarily on the introduction of fruit trees that were important as a source of food.
This practice has continued with greater or lesser intensity up to the present day, reaching a peak during the past two centuries when man was settling the vast expanses of the Americas, Africa and Asia. At first, these plants were imported as novelties for parks and landscape gardens, but, later, economic reasons also prevailed, and exotics were planted in forestry plantations.
The white ash reaches a height of 30 to 40 metres and the bark is more coarsely furrowed than that of the common ash. It also differs from the latter in having brown buds. The odd-pinnate leaves are composed of broader, ovate leaflets and the seeds are narrowly lanceolate, about one-half narrower than the tongue-shaped wings. The seed, unlike that of the common ash, germinates in the spring of the following year. As it grows no faster than the common ash and its wood is of poorer quality it is not cultivated in European forests, though it has some value as an ornamental specimen tree in parks and avenues, especially on the poorer soils.
The manna ash is a tree of south-eastern Europe, where it grows south of the Alps and Carpathians. It occurs in Spain and southern France, but the chief centre of its distribution is Italy and the Balkan Peninsula, where it is found on dry, sun- warmed slopes in oak forests. In the northern areas of its range, it occurs chiefly on limestone soils. In the mountains it may be found at elevations up to 1200 metres.
Pines from the lower, dry elevations of central Europe, on the other hand, have broad crowns to shade their site as much as possible. Similarly, mountain spruces growing at high elevations, or in cold valleys, have slender, narrow crowns.
The main reasons for the introduction of new trees from other regions or continents is for their fruit, to increase the yield of timber, or to enrich the assortment of ornamentals. The introduction of new plants dates from long ago; its beginnings can be traced to the cultured peoples of ancient times, who concentrated primarily on the introduction of fruit trees that were important as a source of food.
This practice has continued with greater or lesser intensity up to the present day, reaching a peak during the past two centuries when man was settling the vast expanses of the Americas, Africa and Asia. At first, these plants were imported as novelties for parks and landscape gardens, but, later, economic reasons also prevailed, and exotics were planted in forestry plantations.
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One garden planning tip is that slatted wooden stagings are necessary for standing plant containers on in the garden so excess water can drip through on to the floor.
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