Foothills Fescue Range Plant Community Guide - Sustainable ...

How do management changes affect plant communities?
When disturbance impacts are reduced or removed, the present plant community may
react in a number of ways. It may appear to remain static, or it may move toward a
number of identifiable plant communities, including the potential natural community.
Some rangeland communities due to disturbance history or a natural process of invasion,
have become dominated by non-native species called modified plant communities. To the
best of our knowledge, long-term rest of these modified plant communities will not return
these to native plant communities. When non-native plant communities are being
evaluated (not including tame pasture at this time), a separate set of questions are applied
to determine the health status of modified plant communities.
How can I tell the ecological status of a plant community?
The plant community tables provide guidance in understanding the ecological status of a
given plant community:
• The range plant community column normally contains plant communities considered
to be the Reference Plant Community(RPC) or site potential.
• The next column to the right shows plant communities that are seral. These
communities have had some modification due to disturbance with seral status
declining as you move down the column.
• The next column to the right of the seral communities column summarizes seral
modified communities where disturbance history has altered the plant communities to
a non-native or modified status.
7.2 Question 2 - Plant Community Structure
What is plant community structure and why is it important?
This parameter recognizes the importance of structure associated with the canopy cover of
major life form groups (trees, shrubs, forbs and graminoids) in a plant community. A
diverse plant community supports optimum nutrient cycling and energy flow. Different
life forms or life form groups vary in canopy structure and rooting depths, using sunlight,
water and nutrients from different zones in the vegetation canopy and soil. Plant
community structure is important in maintaining net primary production, especially in
forested rangelands, and in the maintenance of habitat values for a spectrum of wildlife
species including browsing opportunities for ungulates and feeding and nesting sites for
breeding birds. In grasslands plant community structure also contributes to snow capture
and retention.
Scoring structure in the Foothills Fescue grassland
• rough fescue grassland will normally have a tall grass and forb layer including rough
fescue, a number of native wheatgrasses and a number of tall forbs
• Parry oatgrass and Idaho fescue will identify a mid-grass structural layer
• healthy Foothills Fescue grasslands normally have a rich layer of low grasses and low
forbs filling in the spaces in the canopy between the larger bunchgrasses
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