- Grant County)
(From Atlas of Oregon Lakes, Johnson et al. 1985) Strawberry Lake is located in the Strawberry Mountain Wilderness, an area of about 50 square miles in the Malheur National Forest of eastern Oregon. It is an area with an interesting and complex geologic history. The Strawberry Mountains were built by igneous intrusions and volcanic activity. Strawberry Mountain, for example, is the erosional remnant of a much larger volcano. During the Pleistocene Epoch the mountains were glaciated, forming the spectacular variety of landforms seen today. Strawberry Mountain, 9038 feet above sea level, dominates the small wilderness, which is sprinkled with high mountain meadows and small lakes. Strawberry Lake, which is the largest, lies in a glacial valley. However, it was actually formed by the impoundment of Strawberry Creek behind a landslide dam. The lake overflows the dam of jumbled rock only at high water levels. Otherwise, water seeps through the rock, reappearing at the surface several -hundred feet downsteam.
Strawberry Lake is only a short hike from the wilderness boundary and serves as a base from which to explore the rest of the region. The lower end of Strawberry Lake is a popular spot on summer weekends, and trails lead around the lake and into the high country. Unfortunately, overuse of the area around the south end of the lake has necessitated restrictions on camping within 100 feet of the shore. The lake is open for fishing all year, but is sometimes not accessible because of heavy snow. There is good angling for brook trout, with some rainbow trout also taken. An early rancher named Strawberry Creek for the wild strawberries growing along its bank; the name gradually spread to the mountain and the lake.
Strawberry Lake is very shallow; nearly the entire southern half of the lake is less than 10 feet deep; and it thus has little tendency to develop thermal stratification. Major ion concentrations in the lake are quite low. However, the concentration of phosphorus is surprisingly high and would seem to indicate a rather eutrophic lake, although other indicators do not support this classification. The water remains sufficiently transparent for the bottom to be visible even at the maximum depth, 27 feet. There is no evidence of oxygen depletion, and the surface pH remains low, both implying oligotrophic conditions. The heavy wilderness traffic in the area has caused water quality problems. For example, the lake water sometimes has shown evidence of the presence of a few fecal coliform bacteria. It is possible that the heavy recreational use is contributing to increased bacteria and phosphorus in the lake. The lake is presently classified as oligotrophic.