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:

   No rills present. Some minor rill development may occur where this site occurs below exposed bedrock or other water shedding areas where increased runoff may occur. Where rills are present, they should be fairly short (3-6 feet), <1 inch deep and somewhat widely spaced (4-8 feet). Rills may increase in lenght (4-8 feet) and decrease in spacing (3-6 feet)on slopes greater than 40 percent. A minor increase in rill development may be observed on all slopes following major thunderstorm or spring runoff events but should heal during the next growing season.

2. Presence of water flow patterns:

   Very minor evidence of water flow patterns may be found around perennial plant bases. They show little evidence of current erosion. They are expected to be short (3-6 feet), stable, sinuous, and not connected. There may be very minor evidence of deposition. Evidence of water flow may increase somewhat following significant spring runoff events or major thunderstorms, but should heal during the following growing season.

3. Number and height of erosional pedestals or terracettes:

   Perennial vegetation shows very little evidence of erosional pedestalling (< 1% of individual plants). Plant roots are covered and litter remains in place around plant crowns. Terracettes should be absent or, if present, stable. A slight increase in both pedestal and terracette development may occur with increasing slope.

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

   20-25% bare ground. Soil surface is covered by 35 to 60 percent gravels and/or channers. Bare ground spaces should not be greater than 1 foot in diameter.

5. Number of gullies and erosion associated with gullies:

   No gullies present on site. A very few gullies may be present in landscape settings where they transport runoff from areas of greater water flow such as exposed bedrock. These gullies will be limited to areas where this runoff accumulation occurs. Any gullies present should show little sign of accelerated erosion and should be stabilized with perennial vegetation.

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

   None. No evidence of wind generated soil movement is present. This site is covered with gravel and/or channers on the soil surface which help armor it and reduce the potential for wind erosion. Wind caused blowouts and deposition are not present.

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

   Most litter resides in place with some minor redistribution downslope caused by water movement. Minor litter removal may occur in flow channels with deposition occurring within 1 foot at points of obstruction. The majority of litter accumulates at the base of plants. Some grass leaves and small twigs (grass stems) may accumulate in soil depressions adjacent to plants. Woody stems are not likely to move. A minor increase in litter movement is expected (up to 2 feet) as slopes approach 15% and/or following heavy thunderstorms.

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

   This site should have a soil stability rating of 5 or 6 under the plant canopies, and a rating of 4 to 5 in the interspaces. The average rating should be a 5.

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

   (Lanver) Soil surface 0-3 inches. Texture is a very channery sandy loam; color is brown (10YR 6/3); and structure is moderate thin and medium platy parting to weak very fine subangular blocky. Ochric epipedon ranges from 0 to 3 inches. Use the specific information for the soil you are assessing found in the published soil survey to supplement this description.

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

    Surface coarse fragments combined with perennial vegetation produce sufficient cover and spatial arrangement to intercept most raindrops and reduce raindrop splash erosion. Litter on soil surface and cryptogamic crusting, where present, also protect soil from splash erosion and encourages a higher rate of infiltration. Plant spatial distribution should slow runoff, allowing additional time for infiltration. Bare spaces are expected to be small and irregular in shape and are usually not connected. Vegetative structure is usually adequate to capture snow and ensure that snowmelt occurs in a controlled manner, allowing maximum time for infiltration, and reducing runoff and erosion in all but the most extreme storm events. When perennial grasses and shrubs decrease due to natural events (i.e., drought, insect damage, etc.) which reduce ground cover and increase bare ground, runoff is expected to increase and associated infiltration be reduced.

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

    None. This soil contains significant amounts of coarse fragments throughout the profile. Sandstone bedrock occurs at about 36 to 40 inches.

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:

    Perennial bunchgrasses (Salina wildrye, Indian ricegrass), >> Non-sprouting shrubs (shadscale, broom snakeweed), > Sprouting shrub (green rabbitbrush).

    Sub-dominant:

    Rhizomatous grasses (James galleta) > = Sprouting shrubs (green ephedra) > Perennial forbs (scarlet globemallow).

    Other:

    A wide variety of other perennial grasses and both perennial and annual forbs can be expected to occur in the plant community.

    Additional:

    Natural disturbance regimes include fire, drought, and insects. Assumed fire cycle of 30 to 40+ years. Functional/structural groups may appropriately contain non-native species if their ecological function is the same as the native species in the reference state. Following a disturbance such as fire, drought, rodents or insects that remove woody vegetation, forbs and perennial grasses (herbaceous species) may dominate the community for a period of time. If a disturbance has not occurred for an extended period of time, woody species may continue to increase. These conditions would reflect natural functional community phases within the reference state.

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

    All age classes of perennial grasses should be present under average to above average growing conditions. There may be partial mortality on individual bunchgrasses and shrubs during drought periods and complete mortality of individual plants during severe drought periods. Slight decadence in the principle shrubs could occur near the end of the fire cycle or during periods of extended drought, or insect infestations. In general, a mix of age classes should be expected with some dead and decadent plants present.

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

    Litter cover will be heavier around perennial plants. Most litter will be herbaceous and depths of 1/4 to 1/2 inch would be considered normal. Perennial vegetation should be well distributed on the site.

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

    Annual production in air-dry herbage should be approximately 250 - 300 #/acre on an average year but could range from 150 - 400 #/acre during periods of prolonged drought or above average precipitation.
    
    

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, Utah juniper, and non-native, invasive annual forbs.

17. Perennial plant reproductive capability:

    All perennial plants should have the ability to reproduce in all years, except in extreme drought years. Green rabbitbrush sprouts vigorously following fire. There are no restrictions on either seed or vegetative reproduction. Some seedling recruitment of major species is present during average and above average growing years.

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