Multiple Indicator Monitoring (MIM) of Stream Channels and Streamside Vegetation

written by Grant Hamilton

Other Names


  • [[field_methods:stubble_height]]
  • [[field_methods:streambank_alteration]]
  • [[field_methods:utilization_-_woody_species_use]]


Multiple Indicator Monitoring (MIM) of Stream Channels And Streamside Vegetation is a protocol for monitoring annual grazing use and long-term trend indicators allowing for evaluation of livestock grazing management. Because it includes procedures for documenting stream condition and trend, the long-term indicators are also useful for monitoring changes that occur as a result of management activities other than grazing.

This method was developed by an interagency team composed of Bureau of Land Management, US Forest Service, and University of Idaho specialists and faculty to offer an objective means of determining the health of a riparian system when making adaptive management decisions on federal lands subject to grazing. Beginning in 2003, this team began a process of developing a reliable and valid method of collecting data. The objectives of this project were to:

1) address multiple short- and long-term indicators, 2) measure the most important indicators relevant to detecting change, 3) use existing procedures to the extent possible, 4) improve efficiency through the use of electronic data collection, 5) yield statistically acceptable results within realistic time constraints, and 6) provide useful data to inform management decisions (Burton, Smith, and Cowley, 2011, p. iii).

The first edition of the MIM protocol manual was released in 2008. A revised protocol which replaced some of the earlier indicators was released in 2011.

MIM seeks to provide a more complete picture of a riparian system’s condition than could be offered by measuring a single indicator. Collecting quantitative data on up to ten indicators simultaneously has the added benefit making the fieldwork process more efficient.


Designated Monitoring Area (DMA) Selection

  • Representative DMA: A reach chosen to be representative of a larger area. Representative DMAs should be located within an identified riparian complex. Riparian complexes are defined by Winward (2000) as “a unit of land with a unique set of biotic and abiotic factors. Complexes are identified on the basis of their overall geomorphology, substrate characteristics, stream gradient and associated water flow features, and general vegetation patterns.” Representative DMAs should be located in areas representative of grazing use (or other use) specific to the riparian area being assessed.
  • Critical DMA: A reach that is not representative of a larger area but important enough that specific information is needed at that particular site. Critical DMAs are monitored for highly localized purposes. Small critical spawning reaches when there may be concentrated livestock use is an example. Extrapolating data from a critical DMA to a larger area may not be appropriate.
  • Reference DMA: A reach chosen to obtain reference data useful for identifying potential condition, and for establishing initial desired condition objectives for a similar riparian complex. A common example is a grazing exclosure where livestock access to the stream is restricted.

Monitoring Procedures

MIM includes 7 indicators for trend monitoring. Data should be collected in 2 to 5 year intervals (Burton, Smith, and Cowley, 2011, p. 12).

  1. Greenline composition (adapted from Winward 2000 and USDI, BLM 1996a): The “greenline” as defined by Winward (2000) is the “first perennial vegetation that forms a lineal grouping of community types on or near the water’s edge.” See Burton, Smith, and Cowley (2011, pp. 13 – 19) for the procedure for locating the greenline and determining its composition.
  2. Woody species height class (Kershner et al. 2004) : Woody species regeneration occurs within a six-foot wide belt on adjacent to the greenline on both stream banks. See Burton, Smith, and Cowley (2011, pp. 44 – 47)for the procedure for calculating woody species height class.
  3. Streambank stability and cover (adapted from Kershner et al. 2004): See Burton, Smith, and Cowley (2011, pp. 47 – 51) for the procedure for determining streambank stability and cover.
  4. Woody species age class (adapted from Winward 2000): See Burton, Smith, and Cowley (2011, pp. 51 – 54) for the procedure for calculating woody species age class.
  5. Greenline-to-greenline width (Burton et al. 2008): Greenline-to-greenline width (GGW) is the nonvegetated distance between the greenlines on each side of the stream. It provides an indication of the width of the channel, reflecting disturbance of the streambanks and vegetation. See Burton, Smith, and Cowley (2011, pp. 54 – 58) for the procedure for calculating GGW.
  6. Substrate (Bunte and Abt 2001): Sampling of bed material is used to determine the effects of channel disturbance. See Burton, Smith, and Cowley (2011, pp. 58 – 63) for a description of the process.
  7. Residual pool depth and pool frequency (Lisle 1987): Residual depth is the average of all differences between riffle crest depth and pool maximum depth in the survey. Pool frequency is a count of all pools encountered divided by the thalweg (maximum) length of the DMA. See Burton, Smith, and Cowely (2011, pp. 64 – 47) for details.

For areas subject to grazing, the following indicators, which should be measured annually are included:

  1. Stubble height: Stubble height is a measure of the residual height of key herbaceous vegetation species remaining after grazing. The measurement may be used in at least two ways: first, to determine when livestock should be moved from the riparian area, often called trigger monitoring, and second, at the end of the grazing season and growing season to help determine cause-and-effect relationships between livestock grazing and stream-riparian conditions and whether livestock grazing management changes may be needed the following year. See Burton, Smith, and Cowely (2011, pp. 23 – 27) for details.
  2. Streambank alteration: Livestock can significantly impact stream systems. See Burton, Smith, and Cowely (2011, pp. 27 – 34) for a discussion on monitoring livestock impacts on streambanks.
  3. Woody species use: For a discussion on assessing the impact of stock browsing on woody plants see Burton, Smith, and Cowely (2011, pp. 34 – 39).

Data Entry and Analysis

The BLM has created MIM data entry and analysis Excel spreadsheet. MS Access databases for analyzing MIM data are in use at the field office level. The BLM plans to make MIM data available agency-wide through a geodatabase (Burton, Smith, and Cowely, 2011, pp. 69 – 74). To download MIM spreadsheets and databases visit the BLM’s Technical References Library and navigate to the Riparian Area Management section.

For more information about the MIM database contact the BLM’s National Riparian Service Team:

Technical References

Burton, T.A., S.J. Smith, and E.R. Cowley. 2011. Riparian area management: Multiple indicator monitoring (MIM) of stream channels and streamside vegetation. Technical Reference 1737-23. BLM/OC/ST-10/003+1737+REV. U.S. Department of the Interior, Bureau of Land Management, National Operations Center, Denver, CO.

  • Most recent edition of the MIM manual with detailed instructions and case studies. Includes lists of needed equipment for data collection and data collection forms. Note that this revised edition contains significant changes from the 2008 edition.

Winward, Alma H. 2000. Monitoring the vegetation resources in riparian areas. Gen. Tech. Rep. RMRSGTR-47. Ogden, UT: U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station.

  • General handbook on monitoring riparian areas. Includes useful information on greenline and woody species assessment.

Additional Resources

Bureau of Land Management National Riparian Service Team website –

Bunte, K. and S.R. Abt. 2001. Sampling surface and sub-surface particle size distributions in wadeable gravel- and cobble-bed streams for analysis in sediment transport, hydraulics, and streambed monitoring. General Technical Report RMRS-GTR-74. U.S. Department of Agriculture, Forest Service, Rocky Mountain Experiment Station.

Burton, T.A., S.J. Smith, and E.R. Cowley. 2008. Monitoring streambanks and riparian vegetation – multiple indicators. Version 5.0. U.S. Department of the Interior, Bureau of Land Management. Idaho State Office. Boise, ID.

  • This is the first edition of the MIM handbook.

Kershner, J.L., E.K. Archer, M. Coles-Ritchie, E.R. Cowley, R.C. Henderson, K. Kratz, C.M. Quimby, D.L. Turner, L.C. Ulmer, and M.R. Vinson. 2004. Guide to effective monitoring of aquatic and riparian resources. General Technical Report RMRS-GTR-121. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fort Collins, CO.

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