48 FLORA. OF WASHINGTON AND VICINITY. 



ber of species, but of individuals, which give any particular flora its 

 distinguishing characteristics to all but systematic botanists; and it is 

 also upon this that in the main depends the commercial and industrial 

 value of the plant-life of every region of the globe. It is often the 

 omnipresence of a few, or even of a single, abundant species that stamps 

 its peculiar character upon the landscape of a locality. This is to a far 

 greater extent true of many other regions, especially in the far West, 

 than it is of this; the vegetation of the rural surroundings of Washing- 

 ton is of a highly- varied character, as much so perhaps as that of any 

 other part of the United States ; and yet there are a comparatively few 

 species which from their abundance chiefly lend character to the land- 

 scape and really constitute the great bulk of the vegetation. 



The most prominent, if not actually the most numerous, of these are, 

 of course, certain trees, and notably several species of oak. Probably 

 the most abundant tree everywhere here, as in nearly all parts of the 

 country, is Quercus alba, the white oak; but Q.Prinus, the chestnut oak, 

 Q. coccinea, the scarlet oak, Q. pahistris, the swamp oak, and Q.falcata, 

 the Spanish oak, are also exceedingly common. The most abundant 

 hickory is Carya tomentosa, the mocker-nut. Liriodendron Tulipifera, 

 the tulip-tree, often improperly called white poi)lar, besides being one of 

 the commonest trees, is the true monarch of our forests, often attaining 

 an immense size. It is a truly beautiful tree, whose ample foliage well 

 warrants the recent apparently successful experiments in introducing it 

 as a shade-tree for the streets of the city. Among other common trees 

 may be mentioned the chestiuit ( Castanea vulgaris, Lam., var. Americana, 

 A. DC), the beech {Fagus ferruginea), the red maple {Acer ruhrum), the 

 sycamore {Platanus occidentalis), the red or river birch [Betula nigra), the 

 white elm ( Ulmus Americana), the sour gum {Nyssa^ midtifiora), the sweet 

 gum {Liquidamhar styracifiiia), the scrub pine {Pinus inops), the pitch- 

 pine (P. rigida), and the yellow pine (P. mitis). 



Of the smaller trees, Cornus florida, the flowering dogwood, and Gercis 

 Canadensis, the red -bud or Judas tree, are very abundant and chiefly 

 conspicuous in the spring from the profusion of their showy blossoms; 

 all three species of sumac are common; HamamclisVirginica, the vf itch- 

 hazel, and Viburnum prunifolium, the black-haw, abound; Sassafras offi- 

 cinale, the sassafras, Castanea pumila, the chinquapin, and Jimiperus 

 Virginiana, the red cedar, also belong to this class. 



Of the smaller shrubby vegetation we may safely claim as abundant 

 Cornus sericea and C. alternifolia, the silky, and the alternate-leaved 



