Caring for the Green Zone

Article Abstract
Cathie Erichsen Arychuk, P.Ag.
Bison Production Specialist
AAFRD, Fairview

Summary

Riparian areas, the banks of creeks, streams and sloughs, are important forage producing areas in pastures.  They are also sensitive to damage during grazing and deserve special management.

Caring for the Green Zone

Different management on either side of a fence can make such a difference in the appearance of a stream.  On one side, the banks are trampled, the trees and shrubs are gone, the water is muddy from erosion.  On the other, the stream supports a community of trees, shrubs, sedges and grasses.  The banks are stable and erosion is minimal.  Often, riparian areas are not treated with care.  In the past we have focussed on upland pasture management, determining sustainable use levels and fixing management problems.  Since 98% of our rangelands are uplands, this focus has not been completely wrong.  However, it overlooks the limited but important riparian areas.

Over the past thirty years, research by range managers, biologists and hydrologists has shown the value of riparian areas.  The are important areas for forage production.  They maintain fish and wildlife populations.  They provide water, both surface and groundwater, to sustain human communities.  The two percent of our rangelands consisting of riparian areas are much more important than their size indicates.  Riparian areas are different than uplands and need to be managed differently.  Careful management will maintain healthy riparian areas.  It will also help restore damaged areas.

• Good range management principles promote riparian area health.  These principles imitate the natural system and foster healthy native plant communities, both on uplands and in riparian areas.  The four key principles are:
• Balance animal demand with available forage supply.  This means harvesting forage, but leaving enough carryover to protect plants and soil.
• Distribute livestock evenly.  Many management tools can be used to spread the grazing load over the landscape.
• Avoid or minimize grazing during fragile or vulnerable periods.  For riparian areas, this may be when stream banks are saturated with moisture and vulnerable to trampling.
• Provide effective rest after grazing.  Giving plants time to rest when growing conditions are favourable rebuilds roots, energy supply and vigour.

Successful riparian area management depends on healthy vegetation to build strong stream banks.  It ensures enough vegetation to slow water, trap sediments and maintain stream channel shape during high flows.  It provides protection during vulnerable stages to prevent trampling of banks and maintain woody and grassy vegetation.

Riparian areas - the green zone - are important components of any farm or ranch.  Proper management will ensure they remain productive.