Research on the 

Ecosystem Effects of Cryptobiotic Crusts


Buckhorn Cirque

Olympic Mountains, Washington

            This alpine basin of Buckhorn Mountain in the Olympic Mountains of Washington State is a unique area of alpine tundra at 6500 ft elevation (47° 62’ N, 123° 07’ W).  The central slopes of the basin, underlain by both sedimentary and basaltic rock, are undergoing active downslope soil movement and are dominated by a cover of cryptobiotic crusts and scattered alpine plants (e.g. Antennaria rosea, Arenaria sp., Carex sp., Douglasia laevigata, Luzula sp., Phlox hendersonii, Salix nivalis, Smelowskia calycina, etc.).

             Two distinct types of cryptobiotic crusts occur in the basin: a thin surface layer of mosses (< 2 cm) and foliose lichens over a very coarse mineral substrate (the “crusted site”) and a relatively thick (3-10 cm) surface mat of fruticose lichens (the "lichen" site - dominated by species of Cetraria). The vascular plant community of the crusted site is dominated by Salix nivalis, while the lichen site is characterized by vascular species such as Campanula rotundifolia, and a number of graminoids ( e.g., Carex phaeocephala, Festuca saximontana, Trisetum spicatum) and composites (e.g., Senecio lugens, Solidago multiradiata).  The cirque also contains "noncrusted" surfaces that consist of exposures of coarse-grained mineral substrate with widely scattered vascular plants.  These sites occupy concavities with late-lying snow. 

The photo below shows Buckhorn Cirque from near the summit of Buckhorn Mountain.  Study sites in each of the three surface types are indicated.


The work from this study is being published as:

Gold, WG, Glew KA, and LG Dickson (2000) Functional Influences of Cryptobiotic Surface Crusts in an Alpine Tundra Basin of the Olympic Mountains, Washington, U.S.A. Submitted to Arctic, Alpine & Antarctic Research (Nov. 1999).