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34 and for this reason it is successfully used to cover railway and road embankments in France. It will not grow well on compact clay or on chalky or absolutely poor soils. In England it has only been planted as an ornamental tree, and it is very suitable for planting in towns, as it is not injured by smoke and is free from insect attacks and fungous diseases. Though it suckers freely, this is no objection in streets, where the pavements or wheel traffic prevents them from making an appearance. The young shoots are often killed by frost, but this only serves to keep the tree within bounds without the use of the pruning knife. The Ailanthus only makes one shoot annually, late in the spring, which continues to grow till October or November, and this is the reason why it is spring tender, as the tips of the shoots do not become properly lignified. The tree, however, bears the greatest cold in winter, and was not injured by the severe frost of 1879.

The tree produces flowers in England when it is about 40 feet high; and it fruits pretty frequently, but the seeds are often infertile.

When the Ailanthus is cut back annually, it grows rapidly and produces foliage of enormous size, suitable for the so-called tropical garden. Leaves of plants so treated have measured as much as 4 feet long and 15 inches wide.

The Ailanthus succeeds in a great variety of climates, and is planted in regions so diverse as Northern India, the United States, France, Germany, and Italy. In France it has not been successful as a forest tree, as it is not a social species, and is speedily dominated by native trees, if it survives the seedling stage, when it is sensitive to spring frosts. In warmer climates it easily regenerates by seed, and in consequence has become naturalised in many parts of Europe (as on the arid slopes of Mount Vesuvius, where it stands very well the drought), and in the United States, where it often runs wild in old fields. American writers praise the tree for the value of its wood and the rapidity of its growth, as it is said to make timber faster than any of the native trees that are used for firewood.

The wood is yellowish or yellowish green, and is not clearly distinguishable into well-marked heart and sap woods, though in old trees the centre of the stem becomes deeper in colour. The wood has a specific gravity of 0.6, and is easily worked, taking a good polish. It rives easily. It is used by wheelwrights as a substitute for elm and ash; but is inferior to these, as it does not possess their elasticity or their capability of resistance to fracture. It is said, however, to bear well alternations of dry and wet.

Mr. J.A. Weale of Liverpool, who has paid great attention to the study of timbers, and knows more about them than any one in the trade in this country, writes to us that this wood resembles that of the ash so closely in structure, that the only real difference between the two is in the large cellular compound pores which are formed in the Ailanthus, as shown in the microscopical section which he enclosed.

Elwes is assured by Prof. C.S. Sargent that it makes nice furniture, and he has a specimen from a large tree which was cut down in the Palace Gardens at Wells, Somerset, of which the timber was bought by Mr. Halliday, a cabinetmaker, for £8.