Migratory Work Waves in the Skykomish Valley

cm. The great reduction involved in adapting even a part of it to the purposes of our design made necessary the omission of many details , conspicuously place names and the tracks of Vancouver's ships. The symbols for mountains are also simplified and greatly reduced in number. The conventionalized symbols representing missions , in California south of S-an Francisco Bay, though barely distinguishable in the design, are, relatively to the scale of the drawing , much enlarged from their modest size on the original, as is also the lettering of the names "New Georgia" and "New Albion." Migratory Work Waves in the Skykomish Valley LIi(INAIiI) O. KlCMAN Skylannlsli, Washington The Skykomish Valley of Washington , sometimes called the Steven 's Pass region, is one of several valleys which head at the divide of the Cascade Mountains. The upper valley enclosed by steep mountain walls forms the "pan handle" of King County ; the lower valley, beginning at Gold Bar comprises the southern part of Snohomish County. The entire valley has a length of seventy miles, with approximately thirty miles included within the Puget Sound Lowland . In surface, southern Snohomish County rises gently from the coast, extends eastward in a series of rolling hills and valleys, continues with numerous plateaus, and then turns sharply upwaard in the more precipitous slopes of the Cascades. The upper valley has a fairly steep gradient which increases as the pass is reached. The Skykomish River proper is formed by the junction of the Tyc, Beckler and Foss Rivers near Skykomish . The North Fork joins the river at Index. This river system drains an area of approximately three hundred fifty-five square miles. The Valley is definitely in a youthful stage of erosion. The upper valley is bounded by steep mountain slopes. A steep gradient causes a rapid flow and many falls along the river's course. The tributaries in many cases do not join the consequent drainage with accordant junctions and many lakes and marshes have as yet not been touched by this youthful drainage system. Although still in the stage of youth, the drainage pattern in the lower valley is more advanced. This results from the greater amount of leveling done by the Pug'et Sound glacier. The lower valley is characterized by low, rolling , lateral moraines, the valleys of which often contain lakes and undrained marshes. The glacier had its origin to the northward and the morainic relief consequently runs in a north-south direction. The upper valley comprises a well defined physiographic unit. From the cirque at the summit, to the point of mergence with the lower valley, it has all the characteristics of a hanging valley. Although somewhat sinuous, it has a "U" shaped floor practically its entire length, and nowhere is it over a mile and a half in width. The floor is profusely strewn with glacial erratics , and prominent spurs project at intervals from the valley shoulders . (5) Climatic Characteristics The Skykomish Valley is within the temperate marine climatic area of the Pacific Northwest, characterized by mild wet winters and cool summers. The region is situated directly in the path of the everchanging cyclonic storms. In the winter months, the valley is drenched with rain by the prevailing westerlies as they sweep landward, dropping their load of moisture as they become cooled by the land mass. During the summer months this is reversed, as the land is then warmer than the ocean with the resultant lower rainfall, some months being almost rainless. In a mountainous area of this type the relation of precin'tation to topography is so pronounced that a rainfall and topographic map of the region show definite co-relations. The precipitation figures available give Monroe 43 inches per year and Startup 60 inches ; Scenic, with an elevation of 2224 feet, has "S3 inches. There is likewise a definite relationship between snowfall and altitude, although data are not available from many stations. Monroe at an elevation of 72 feet averages 11 inches of snow per year. The now-abandoned station of Tye —3110 feet, the highest noint at which consecutive records have been kept—averaged 332 inches of snow annually over a 13 year period , Such a heavy snowfall...