The high water of 1957 (4,393.2 ft) flooded and killed many yellow pine and lodgepole pine trees. The oldest one found, a yellow pine that grew on level ground just above the highest water level, had 185 annual growth rings at a point 15 inches above its base. The summer growth rings were narrow for the dry years 1924, 1926, and 1955. They were very narrow for the periods 1791-97 and 1813-14, possibly because of the flooding of some of the roots by high stages of the lake. The rate of tree growth near Lakeview was much above normal in the periods 1790-94 and 1805-25 (Antevs, 1938, p. 66; Keen, 1937, fig. 7), and presumably the precipitation and runoff in those periods were also above normal. The level of Davis Lake probably was high then.
Many young western yellow pine trees, up to 1 foot in diameter, had the ability-not shared by mature yellow pines-to survive repeated shallow flooding by Davis Lake for periods of 60 days or more in several growing seasons of the 1950’s. Hence, the ages of trees of this species are not exact, dependable indices of the length of time since the lake water covered the level of the bases of the trees; consequently, the 185-year-old pine tree mentioned above may have survived in its youth (perhaps about 1813) a stage as high as the one that built the bar at altitude 4,395.4 feet.
Variations in tree-ring growth over the past 650 years indicate that climatic and lake-level variations like those of recent decades probably have occurred before in the short life of Davis Lake. Ponderosa pines have a lifespan that may exceed, 750 years (Keen, 1937, p. 176). Some within 3 feet of the high lake level of 1957 are so large that they probably have lived more than 600 years. Keen (1937, p. 176, 188) established cross identification between growth rings of pine trees near Watkins Butte, north of Fort Rock, Oreg., for 650 years before 1935, and concluded that in that period there has been no general trend toward wetter or drier years, and that average growth for the period 1900-19 was identical with the average growth during the past 650 years. Keen (1937, p. 188) found that
the present [drought period, 1917-85] is the most severe and critical that the present forests have experienced in ‘the last 650 years. Several other periods have exceeded the present one in duration of subnormal growth, but none has approached it for severity.
On the other hand, he found (Keen, p. 186, fig. 8) that the tree growth in many periods in the last 650 years had exceeded that of any year or short term of years since 1850. From those conclusions, the low lake stages of the 1930’s may inferentially recur less often than the high stages of 1904 and 1957.
