Alpine Restoration in Colorado's Rocky Mountains

These approaches to restoring closed social trails on Colorado's 14,000-foot peaks were developed by Jim Ebersole, Robin Bay, and Dave Conlin.  This handout was prepared by Robin Bay for use at Colorado Fourteeners Initiative staff trainings.

Jim Ebersole home page

Restoration & Revegetation Methods

Restoration Training

Colorado Fourteeners Initiative

 Prepared by Robin Bay

9 June 2001

Goals of ecological RESTORAtION

            •  Reconstructing the original drainage system

            •  Maximizing the system’s ability to retain water - to avoid water channeling

            •  Restoring the function and structure of the vegetation

            •  Restoring species composition

            •  Maintaining native genetic diversity

            •  Soil conservation and stabilization

            •  Aesthetics

Levels of restoration - USFS guidelines

Type I   -  Restoration attempting to enhance all biotic and abiotic factors of disturbed zone in order to restore the natural processes of the system.  Common methods are threefold: slope stabilization, revegetation, post-closure research and monitoring.  These methods include: seeding, turf transplanting, seed propagation, soil enhancement, etc.

            Type II  -  Closing of social trails, signing, seeding, construction of check dams to mitigate erosion, and transplanting.

Type III - Closing and disguising of social trails in an attempt to keep hikers off non-system trails.

            Type IV - Passive restoration - closing trails and allowing natural succession to occur.

steps to restoration

            •  Outlined below are the steps required for Type I restoration. If a different level of restoration is prescribed then not all of the
            steps would be followed to the same extent. 

•  The methods and results described here are based on what we currently know about alpine revegetation.  As more restoration and revegetation projects are completed here in Colorado and at other locations, new information will be added and the methods will undoubtedly be altered and improved.

Step 1: Closing social trails

Goal:  Keep hikers off       

            •  Signs

            •  Rock barriers

            •  Disguising the trail (willows, branches)

            •  Rock fill

 Step 2: Stabilizing social trails

Goal: Stop erosion and attempt to recreate the original contour of the slope         

            •  Terracing - should be back filled at an angle to match original contour

            •  Crib steps in steep trail sections

            •  Check dams to mitigate water channeling

            •  Drainage structures to remove water from trails

 Step 3: revegetation

Goal: Restore the function and structure of the vegetation

Considerations

            •  Vegetation cover that can be achieved in a short time

            •  Cost of implementation (materials and labor)

            •  Materials - plant materials, soil, erosion matting, etc.

            •  Physical effort

            •  Aesthetics

Active revegetation

I.  Seeding

Considerations

            •  Least time and effort required

            •  Low cost

            •  Slow to achieve vegetation cover

            •  Very susceptible to disturbance, climate change, etc.

Implementation

            •  Best to use native seed collected near to the restoration site

                        - Important to collect from the same microhabitat where seed will be spread

            •  Use the dominant species in the community

            •  In general better to use a mix of species including those with different life histories and               

               physiological traits (mixture of graminoids and forbs)

            •  Seed should be collected after seeds are mature, usually in late August/early September

            •  Mature seeds (especially of graminoids) will often fall out in your hand

            •  It is okay to collect some of the inflorescence with the seeds, but try to break it up as 

               much as possible before spreading

            •  If seeds are not spread immediately they should be stored cool and dry         

            •  Spread seed at rate of 20 - 40 g/m² (wet weight including some inflorescence material)

            •  Rake area to loosen soil before spreading seed

            •  Cover seed with a thin layer of soil so it is less likely to blow or wash away (you can use

               the soil that was raked off. 

            Table 1.  Some common species that have been successful for seeding in the alpine.  This is       by no means a complete list of possible species.  Any common species present can be used.

            (Pictures and descriptions of these species are attached at the end of this packet.)

II. Turf Transplanting

Considerations

            •  Very good vegetation cover in short time period

            •  Very time intensive

            •  High physical effort

            •  Requires a lot of plant material, but should only be done when turf is available from trail construction

            •  Does not work if done sloppily

Implementation

            •  Remove turf from new trail construction in blocks attempting to excavate root systems as much as possible

            •  Blocks should be a least 5 x 5 in. and as deep as possible within the trail construction guidelines

            •  Turf blocks should be transplanted the same day or the next day to maximize success

            •  If it is necessary to stock pile turf,

                        - put it in the shade if possible (at treeline)

                        - place block edges close together, heap dirt around outside so edges don’t dry out

                        - sprinkle with water daily if not raining

                        - don’t leave for more than a week or the vegetation underneath will die

            •  Dig in blocks so that vegetation is flush with ground surface and all roots and edges are buried.

            •  Rocks can be placed in between turf blocks to stabilize them

                        - Never remove rocks from the tundra near the trail!

            •  Probably can be done at any time in the growing season.

III. Plug transplants

Considerations

            •  Pretty good vegetation cover (we have no long term data for this method yet)

            •  Time and labor intensive

            •  We believe best in wet areas

Implementation

            •  Remove small clumps of vegetation from surrounding area excavating as much of the root system as possible.

                        - Important to use plugs from the same microhabitat where they will be transplanted.

            •  Plugs should be 3 - 5 in. in diameter and 5 in. deep cylinders, tapered as little as possible.

            •  Remove plugs at least 3 ft. from the trail and fill in holes with soil or rocks.

            •  Dig holes slightly larger than plugs and fill in around plugs with the excavated soil.

            •  Place plugs 5 - 8 in. apart.  Attempt to create clumps and not just a straight line of transplants.

            •  We believe this method will be most effective in wet areas. 

            •  We initiated the first trial of this method in the Rocky Mountains during the summer of 2000 on Mount Harvard, thus no data is yet available evaluating the success.

Passive restoration - Natural seedling establishment

Considerations

            •  Involves no time, physical effort, or materials

            •  Slow to achieve vegetation cover

            •  Will not hold soil in place

            •  Will not work if the seed bank is badly damaged - the upper soil horizon gone - or where       there        is soil movement

Implementation

            •  Most successful in mildly disturbed areas with little erosion, very low slope angle, and nearby seed sources (i.e. mature vegetation)

•  Mature vegetation can also act as a “safe-site” for developing seedlings providing protection      

   from environmental hazards.

            •  This method may have beneficial use between turf blocks or single species transplants. 

            •  Seedlings will likely naturally colonize gaps of up to 20 cm between turf blocks - which means               that turf materials can be placed farther apart so that they can cover more area.

Erosion Matting

Considerations 

•  Increases success of single species transplants, seeding, and probably would improve natural    seedling establishment as well.

            •  Heavy and expensive

            •  Not aesthetically pleasing to some hikers

            •  Not always allowed in Wilderness Areas

Implementation

•  Recommend Curlexâ excelsior erosion matting made with aspen fibers held together with

cotton netting.  There are also mats with straw, jute and other fibers that we have not tried.

            •  Tack down with 6" staples every meter, place rocks on the edges, and dig in the ends (especially           the uphill end)

            •  Rolls are 4' x 180' and weigh approximately 80 lb.

Step 4: MAINTENANCE & Monitoring

Considerations 

            •  If implemented correctly none of these methods should require maintenance

            •  It takes a little longer to implement revegetation in such a way that they can be monitored, however if done well it can serve as a resource to further our knowledge and understanding of revegetation methods

            •  Monitoring and evaluating the success of past restoration/revegetation projects can ultimately lead to even more successful future projects

Implementation

            •  Always record the method used, date, and exact location with photos if possible, drawings are also good

            •  Record the estimated area revegetated

            •  When seeding or transplanting plugs record the species used and the amount of plant material used

            •  Photo-degradable erosion matting will not completely degrade above treeline and will often have to be removed after several years.  It is also often necessary to return to the site after several years to remove any debris used to disguise the trail.