Home garden design > Tree identification > Ailanthus tree

Ailanthus tree

The Ailanthus tree, which landed here from China about one hundred years ago, has called much attention to itself ever since. I saw it first in a big city - a strange tree standing with all the stately dignity of all English elm at the head of the street. But, unlike the elm, it was clothed with foliage of tropical luxuriance, and against the fern-like leaves lay masses of half-ripe seeds, flushing pink and green, strongly resembling, at a little distance, the great flower clusters of the hardy hydrangea.

I saw Ailanthus trees next on a rough hillside - hundreds of lusty saplings. Unmindful of the protests of the lawful owner, they had seized the land. On the sober conventional city tree, the average twig was no thicker than an ordinary lead pencil. But here, with the restraints of civilization removed, there was evidently going on a free-for-all race among these wild youngsters. I call easily imagine that many records were being broken, for I measured a single shoot that was eight feet long and almost two inches in diameter at its base. It bore thirty­four leaves, the largest of which was three feet six inches long, and where it broke off, the scar was easily al inch in length. "Tree of Heaven," indeed! I never before saw a tree so aspiring. But the name the farmer calls it by is "Devil's Bush." Because he cannot contend successfully with it, he stands back and calls down maledictions on its leafy head.

A queer freak of certain of these Ailanthus shoots was the broadening and flattening of the tips and the irregular crowding of the side buds. In the branch from which the drawing was made later the tip had been severely injured, and instead of lengthening, the end curled around, and a multitude of undersized leaves rose in a very small space, forming a huge rosette.

A similar crowding of leaves produces on willow trees the familiar pine cone willow galls which are described a few pages farther on.

By these tufted Ailanthus branches I am strongly reminded of an abnormal growth we often see among the branches of willow and hackberry trees. Sometimes it is the egg of a gall insect; sometimes it is the spore of a fungus that perverts the growth of the soft tissues of a terminal shoot. Whichever is the cause, the result is the checking of the upward growth. The stem throws out side shoots in profusion, and these crowd and stunt each other, producing the matted bunch of twigs which is called a " Witches' Broom."

It is no surprise to learn that the relatives of the Ailanthus tree live in the tropics. Its exuberance of growth proclaims its racial nativity. It is the sole American representative of a family that contains twenty­seven genera and one hundred and forty-seven species. The bark of the Ailanthus is smooth and fibrous, light brown, showing paler beneath, where it breaks into furrows. In the towns, staminate trees should be cut down, as the odor of the flowers is unpleasant to all, and even distressing to people who have catarrh. Pistillate flowers have no such odor. The tree spreads freely by suckers, and the abundant seeds are winged for long flights through the air. A very popular use of the tree is to start a few and clit them back to the ground each year. Under this systematic abuse, they send up leafy shoots of great size, which form a beautiful screen of shrubbery - like a fern bed, but more lusty and so more tropical-looking.