Rangeland health reference sheet

Interpreting Indicators of Rangeland Health is a qualitative assessment protocol used to determine ecosystem condition based on benchmark characteristics described in the Reference Sheet. A suite of 17 (or more) indicators are typically considered in an assessment. The ecological site(s) representative of an assessment location must be known prior to applying the protocol and must be verified based on soils and climate. Current plant community cannot be used to identify the ecological site.

Indicators

1. Number and extent of rills:

   None

2. Presence of water flow patterns:

   Typically none. If present (steeper slopes following intense storms) short and not connected.

3. Number and height of erosional pedestals or terracettes:

   None, due to the slope percentage and amount of cover. Pedestals and terracettes are indicators of soil being moved by water and/or wind.

4. Bare ground from Ecological Site Description or other studies (rock, litter, lichen, moss, plant canopy are not bare ground):

   Less than 5% bare ground is found on this site, with bare patches generally less than 2-3 inches in diameter. Extended drought can cause bare ground to increase. Bare ground is the remaining ground cover after accounting for ground surface covered by vegetation (basal and foliar canopy), litter, standing dead vegetation, gravel/rock, and visible biological crust (e.g., lichen, mosses, algae).

5. Number of gullies and erosion associated with gullies:

   None. Gullies are not a natural feature of this landscape and site.

6. Extent of wind scoured, blowouts and/or depositional areas:

   None. The vegetative cover in the reference state is sufficient to limit wind-scoured or blowout areas. This site is not a depositional area for offsite wind erosion.

7. Amount of litter movement (describe size and distance expected to travel):

   None. No evidence of litter movement (i.e., dead plant material that is in contact with the soil surface). The inherent capacity for litter movement on a soil is a function of its slope and landscape position.

8. Soil surface (top few mm) resistance to erosion (stability values are averages - most sites will show a range of values):

   Stability class ratings from the soil stability test should be =5 overall, with ratings of 5 or greater in the interspaces and under perennial plant canopy. Plant canopy is large enough to intercept the majority of raindrops. No physical crusts apparent.

9. Soil surface structure and SOM content (include type of structure and A-horizon color and thickness):

   The surface horizon (A) should be a minimum 7" (roots growing throughout) with weak fine granular to moderate fine subangular blocky structure. The surface (A) horizon color is very dark grayish brown 10YR 3/2 (moist), and the subsurface (B) horizon color is dark grayish brown 10YR 4/2 (moist).

10. Effect of community phase composition (relative proportion of different functional groups) and spatial distribution on infiltration and runoff:

    Diverse grass, forb, and shrub canopy and root structure reduces raindrop impact and slows overland flow providing increased time for infiltration to occur. Warm season shortgrasses are dominant. Tall and mid grasses and mid grass cool seasons are co-subdominants. Sedges, forbs, and shrubs are all minor components. Infiltration will decrease if tall and migrasses and mid grass cool season groups become minor or trace. Spatial distribution of functional/structural groups varies from north to south. In the northern part of this MLRA expect more cool seasons and shrubs than in the southern end.

11. Presence and thickness of compaction layer (usually none; describe soil profile features which may be mistaken for compaction on this site):

    There is no evidence of a compacted soil layer less than 6 inches from the soil surface. Soil structure is similar to that described in Indicator 9.

12. Functional/Structural Groups (list in order of descending dominance by above-ground annual-production or live foliar cover using symbols: >>, >, = to indicate much greater than, greater than, and equal to):

    Dominant:

    Group 1 Shortgrass Dominant 40% 680 lbs. blue grama 225-440, buffalograss 75-240

    Sub-dominant:

    Group 2 Tall and mid warm season grasses co-subdominant 21% 360 lbs. sideoats grama 20-150, little bluestem 20-100, big bluestem 0-45, composite dropseed 0-45, sand dropseed 0-45 Group 3 Midgrass cool season co-subdominant 18% 300 lbs. western wheatgrass 200-270, green needlegrass 0-120, needle and thread 0-80, Fendler threeawn 0-15, squirreltail 0-15

    Other:

    Group 4 Sedges minor component 6% 0-105 lbs. threadleaf sedge 0-50, sun sedge 0-30, sedge 0-25 Group 5 Forbs minor component 10% 170 lbs. see ESD for species list minimum 5 species. Group 6 Shrubs minor component 5% 85 lbs. see ESD for species list minimum 3 species.

    Additional:

13. Amount of plant mortality and decadence (include which functional groups are expected to show mortality or decadence):

    The majority of plants are alive and vigorous. Some (<10%) mortality and decadence is expected for the site. This in part is due to drought, unexpected wildfire or a combination of the two events. This would be expected for both dominant and sub-dominant groups.

14. Average percent litter cover (%) and depth ( in):

    Total litter cover is expected to be 60-80% and at an average depth of 0.25 inches. Litter may be reduced to 20-40% in cover and near zero depth for 1-2 years following wildfire or multiyear drought.

15. Expected annual annual-production (this is TOTAL above-ground annual-production, not just forage annual-production):

    Annual production is 1,700 pounds per acre in a year with normal precipitation and temperatures. Low and high production years should yield 900 and 2,200 pounds per acre, respectively. Annual production may be reduced by 40-60% the first year following a wildfire or following a multiyear drought.

16. Potential invasive (including noxious) species (native and non-native). List species which BOTH characterize degraded states and have the potential to become a dominant or co-dominant species on the ecological site if their future establishment and growth is not actively controlled by management interventions. Species that become dominant for only one to several years (e.g., short-term response to drought or wildfire) are not invasive plants. Note that unlike other indicators, we are describing what is NOT expected in the reference state for the ecological site:

    Cheatgrass, Russian thistle, kochia, and other non-native annuals may occur in trace amounts in community 1.1 but they do not have the potential to increase to a subdominant or dominant in the absence of wildfire and act as an invasive on this site. The listed invasives are not expected to occur in the reference state.

17. Perennial plant reproductive capability:

    Plants in all functional/structural groups should be capable of reproducing annually under normal weather conditions. The number and distribution of tillers or rhizomes is assessed on perennial plants occupying the evaluation area. Vigor and reproductive capability may be somewhat reduced during drought or for 1 year following a wildfire. At least 50% of plants should still have reproductive capability during droughts that last 1-2 years.