Botanical studies of rock streams on the western half of Rich Mountain and on the north slope of Mt. Magazine in Arkansas question the common presumption that such streams require periglacial conditions to form, and are now inactive relict features in this area. Trees along the margins of the streams examined show abundant evidence of trauma resulting from Late Holocene movement, in the form of bent and tilted stems. Cross sections of trees demonstrate marked eccentric growth associated with tilting and cambial trauma associated with corrasion by rocks. That this damage is not the result of excessive snow loading is indicated by the lack of such stressed trees away from the stream margins. Stressed growth and shortened lifespan of trees on the Rich Mountain rock stream margins is shown by the small diameter (less than 15 cm) of most, while older and larger trees are found on higher slopes away from the stream. These rock streams are indicated to be moving, active features, not stabilized relicts of the Pleistocene. Further study would permit more testing of this hypothesis and the establishment of a chronology of movements in the last century.

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