FLORA OF CANADA. 
5 
zone or to the south. A noteworthy exception to this general rule is 
Castalia tetragona, the smallest of the water lilies, which in Canada is 
found in the sub-arctic forest only. 
Hardwood Forest Zone. — The hardwood forest zone includes 
all eastern Canada south of the sub-arctic forest with the exception of a 
small region in southern Ontario, extending between the shore of Lake 
Erie and a line running approximately from Toronto to Windsor. 
There is little cultivated land in Eastern Canada north of this 
zone. As its name indicates, it is characterized chiefly by deciduous 
trees, the principal ones being: Basswood ( Tilia americana), Sugar 
Maple (Acer Saccharum ) Red Maple (Acer rubrum), Black Ash (Frax- 
inus nigra), White Ash (Fraxinus americana ), White Elm (Ulmas ameri- 
cana), Yellow Birch (Betula lutea), Red Oak (Quercus rubra), Burr Oak 
(Quercus macrocarpa), Beech (Fagus grandifolia). Of the coniferous 
trees, the White Pine (Pinus Strobus) the Red Pine (P. resinosa), the 
Hemlock (Tsuga canadensis), and the White Cedar (Thuja occidentals) , 
are the most important. 
The underbrush, though very variable and made up of a great 
number of species, is generally rather scanty and becomes conspicuous — 
as a component of the forest — only along its borders or where the woods 
are very open. Among the most typical shrubs may be mentioned: 
Service Berry (Amelanchier spicata ), Moosewood (Dirca palustris), 
Purple Flowering Raspberry (Rubus odoratus), Sumach (Rhus typhina ), 
Poison Ivy (Rhus Toxicodendron), and Arrow- woods (Viburnum alni- 
folium , V. acerifolium, V. cassinoides). 
As the rainfall is abundant throughout the hardwood forest zone, 
the herbaceous vegetation is rich, in both species and individuals, 
everywhere where light and soil conditions permit. In the woods 
proper it is rather insignificant after the foliage of the trees is fully 
developed. In the spring, however, it is very luxuriant, and especially 
where the soil is rich and deep there is a magnificent display of beauti- 
fully coloured and showy forms, for instance: Trillium (Trillium 
grandiflorum , T. erectum, T. undulatum), Bellwort (Uvularia perfoliata), 
Dog’s-Tooth Violet (Erythronium americanum), Showy Orchis (Orchis 
spectabilis) , Jack-in-the-Pulpit (Ariscema triphyllum), Spring Beauty 
(Claytonia caroliniana) , Violets (Viola, blue, white, and yellow forms), 
Hepatica (Hepatica triloba, H. acutiloba ), Dutchman’s Breeches 
(Dicentra Cucullaria), Squirrel Corn (Dicentra canadensis), Bloodroot 
(Sanguinaria canadensis), Pepper-root (Dentaria diphylla), Barren 
Strawberry (Waldsteinia fragarioides) , Flowering Winter-green (Polygala 
paucifolia), Blue Phlox (Phlox divaricata ), etc. Others, less conspicuous, 
but characteristic of the hard-wood spring flora, are species of Sedges 
(Carex), Wild Ginger (Asarum canadense), Blue Cohosh (Catilophyllum 
