62 
tris), and the tree with the thickest trunk is a hybrid between the 
White and the Burr Oaks called Quercus Bebbiana. 
This is a poor region, however, in which to judge the value of many 
Oaks as ornamental trees. It is too cold here and only a few species 
have proved hardy in New England, and of the fifty-five species which 
become trees in the United States it has been found possible to keep 
alive in the Arboretum only seventeen species. Of the shrubby species 
there are in the Arboretum only the Chinquapin Oak {Quercus prinoides) 
and three or four of the Rocky Mountain species which grow very 
slowly here and give little promise of value as ornamental plants. 
Some of the handsomest of the American Oaks, including all the species 
confined to the southern states, to the Pacific coast region, and to 
Arizona and New Mexico, cannot be seen growing in the Arboretum. 
No evergreen Oak can support this climate, and the Oaks of western 
Europe are usually short-lived in eastern America. The deciduous-leaved 
Oaks of western Europe and those of northern Japan, Korea, northern 
and western China, grow well in the Arboretum and a few of these 
already produce good crops of fruit. The largest Asiatic Oaks in the 
Arboretum are plants of Quercus variabilis and Q. dentata on the Oak 
Path near its southern end. The principal collection of Asiatic Oaks, 
however, is on the southern slope of Bussey Hill between Azalea Path 
and the Bussey mansion. In the mixed plantation of trees near the 
summit of Peter’s Hill are many Oak-trees, including large plants of 
the Japanese species raised from seed brought from Japan in 1892. 
Scattered through the Oak plantations are several hybrids of the Amer- 
ican species, and no opportunity is lost to increase the number of these 
hybrids which are now known to occur between various species grow- 
ing in different parts of the country. The oldest of these hybrids now 
known in the neighborhood of Boston is on the Sargent estate in Brook- 
line; it is of uncertain origin, but no doubt was planted by Mr. Thomas 
Lee as early as 1820. This tree is now known as Q. Sargentii and re- 
produces itself quite accurately, and as a young plant grows very rap- 
idly. There are already good-sized trees in some of the Arboretum 
borders. All of these hybrid Oaks are interesting, and some of them 
are handsome trees, like Q. Comptonae in Natchez, Mississippi, for ex- 
ample, a hybrid of Q. lyrata and the southern Live Oak, Q. virginiana, 
one of the most splendid Oak trees in the world but unfortunately of 
too tender blood to bear the severity of a New England winter. 
The early spring is one of the seasons when our northern Oaks can 
be studied to good advantage, for the color of the very young leaves 
and the amount and character of their hairy covering is different on 
every species. These characters are constant from year to year, and 
it is easier to distinguish, for example, a Black Oak {Quercus velutina) 
from a Scarlet Oak (Q. coccinea) by the unfolding leaves than it is by 
the mature leaves which on some individuals of these species are diffi- 
cult to distinguish. In the autumn the leaves of Oak trees turn later 
than most of our deciduous trees; the color, however, is assumed irreg- 
ularly on different individuals of the same species, and on some of 
them they are green while on others they are scarlet or yellow. Oak 
trees form the brilliant feature certainly of the North American forest 
in late autumn, and if for no other reason snould be planted for the 
autumn color of their foliage; it is surprising that they are not more 
