CLIMATE, SOIL, AND VEGETATION. North Da kota has a typical continental climate charac terized by enormous extremes of temperature, which, however, the dry atmosphere renders bearable, healthful, and invigorating. The mean temperature for -January is 3°, and for July 70°. The extremes have a range of nearly 155° for the year, a maximum having been recorded as high as 114°, while a minimum of 40° below zero is not rare. The' average annual rainfall of 17.29 inches would scarcely suffice for the needs of agrieulture were it not for the fact that fully three-fourths of the precipitation falls during the growing season (April to September). In the western half of the State, however, the rainfall is insufficient. for successful agriculture. The deep alluvial deposits of the Red River Valley are of inexhaustible fertility. and arc conspicu ously favorable to wheat-growing. The glacial drift of the prairies forms, in addition, an ex cellent subsoil. hut toward the west it grows poorer and nmre scanty. especially in the south west. Forest growth is found only along the river hanks, and on the Turtle Siountains in the north, and in some of the lied River Valley. The remainder of the State is a tree less prairie covered with numerous species of grasses and other forage plants. The principal
trees are cottonwood along the rivers, and oak, elm. birch. ash, and poplar in the Turtle Moun tain.
GEoLoGv :MINERAL IZESOURCES. The rock formations of the State include the Arch:can, Cambrian, Silurian. Cretaceous, and Tertiary systems. The Dakota sandstone of the Creta ceous system is an important member, being the chief Nvater-bearing stratum on which the arte sian wells of North Dakota depend. Most of the rocks, however. are covered by a deposit of glacial drift, cmnposed of sand, gravel, and clay. In the Ned Inver Valley there is a thick layer of alluvium deposited by Lake whose ancient shorelines have been traced all around the valley. The central and western of the State are underlaid with extensive beds of lignite. which is being more and more utilized. The production in I901 amounted to 166.601 tons, valued at :i;214,151. Clay is the only other mineral utilized to any considerable extent, though some building-stone is available, and lime, salt, and a little iron are found.