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Mountain Ashes. Many of these trees are now growing well in the 
Arboretum, and some of them are unusually full of fruit this year and 
handsome and interesting objects. Mountain Ashes have leaves divided 
into numerous narrow leaflets, compact clusters of white flowers which 
are followed by scarlet, yellow, orange-colored, pink or white, usually 
globose fruit which varies from a quarter to three-quarters of an inch 
in diameter. The best known and most commonly planted of these 
trees in the United States is the European Sorbus Aucuparia, the 
Rowan tree of Scotland. It is a tree from forty to sixty feet tall, of 
pyramidal habit while young, with erect branches which as the tree 
grows older spread out into a broad and graceful head. Here the leaves 
retain their color until the autumn is far advanced, and during Sep- 
tember and October the contrast between the bright green leaves and 
the drooping clusters of brilliant red fruit makes this tree an attract- 
ive object until the birds strip it of its fruit. This Mountain Ash is 
common and widely distributed over the cooler parts of Europe and 
was probably early introduced into North America where it has been 
much planted in the extreme northern states and in Canada. Several 
varieties are recognized. The handsomest of these is the Moravian 
Mountain Ash (var. moravica or dulcis) of northern Austria. This is 
a tall tree with a smooth stem, leaves with narrower leaflets than 
those of the type and larger and sweeter fruit. It is used as food in 
central Europe. This Mountain Ash has grown in the Arboretum very 
rapidly and promises to become a large tree. Two specimens in the 
plantation near the top of Peter’s Hill are now covered with fruit and 
are among the handsomest of the small trees in the Arboretum. There 
are forms of the Rowan tree with pendulous branches (var. pendula) 
and with fastigiate branches (var. fastigiata). There is a form with 
yellow fruit and a variety from eastern Europe (var. lanuginosa) the 
leaves of which are covered on the upper surface with stiff hairs and 
are downy on the lower surface. 
Asiatic Mountain Ashes. In recent years a number of these trees 
have been brought from eastern Asia to the Arboretum and some of 
them promise to be valuable trees here. The Japanese Sorbus com- 
mixta was the first of them which was planted here and it has now 
been growing in the Arboretum since 1888. There is a tall specimen 
of this species on the right-hand side of the path leading to the Shrub 
Collection from the Forest Hills Gate. It has smaller flower-clusters 
than the European species, the bright red fruit is smaller and its chief 
value is in the bright orange and red color of the leaves in autumn. 
A much handsomer plant is Sorbus pekinensis, a native of northern 
China, which is now well established in the Arboretum. It is a slender 
tree with narrow leaflets, compact clusters of flowers and lustrous pink 
or yellowish fruit in drooping clusters. The color of the fruit is unusual 
among Mountain Ashes. The narrow leaflets give this tree a particu- 
larly open and attractive appearance. There are a number of specimens 
in the Sorbus Collection in the low ground near the group of Swamp 
White Oaks on the Valley Road, but the largest and handsomest spec- 
