A unit of Lasting Forests evolving since March 30, 1999
A Total Forest Management Plan and Wildland Management Decision Support System
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Streams of the Ancient Forest

The streams of ancient forest contribute to their structure and functions and in some forests their very presence adds greatly to the perceived quality of such forests to people. Interpreting streams, particularly channel conditions, can suggest the evolution and age of a stream. A "reference standard", a desired condition is neeeded against which to judge the state of a stream channel. Disturbances vary and almost any stream condition can be found along a continuum. Channel changes are complex and influenced by geology, channel geometry, woody debris, bank projections, large boulders, and amounts and timing of precipitation. Quantifying this complexity is challenging, probably impossible (or if done, at least with limited end-use), and thus best addressed by a rough or approximating expert system. The system can provide some quantification and give an index to very old forest conditions...and thus the stream(s) themselves. Perhaps the stream index is an expression of how ancient or undisturbed is the forest.

The current evaluation is based on 11 importance-weighted criteria developed from studies and review of Wood-Smith and Buffington (1996).

A BASIC program requires answers to 13 questions on the following topics

1. Amount of woody debris in the stream
2. Presence of finbe sediments
3. Number of pools
4. Depth of pools
5. Fish speciess richness
6. Stream width
7. Stream depth
8. Change in velocity
9. Channel width
10. Riffle areas
11. Pool areas
12. Presence of scour pools
13. Richness of pool types

The ancient forest stream scores for your tract are:

Area Name and Score

Rushing Run - 89

Peg Creek - 41

A perfect score is 100 but even some streams within superior ancient forests have scores ranging from 85-95.

The scores may change over the years, reflecting aging and protection (or lack of it) of the watersheds of these streams.

Literature

Wood-Smith, R.D. and J.M. Buffington. 1996. Multivariate geomorphic analysis of forest streams: implications for assessment of land use impacts on channel condition. Earth Surface Processes and Landforms 21:373-393.

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This Web site is maintained by R. H. Giles, Jr.
Last revision January 17, 2000.