Cariboo Silvopasture Demonstrates Profitable Sustainability

Zirnhelt Ranch is a family owned and operated ranch located in the Beaver Valley of the Cariboo region of British Columbia.  The Zirnhelt family believes in sustainable food production and use farming methods that minimize the impact on the natural environment.  As well, the family ranch manages a woodlot and operates a timber frame building company located on the ranch.

Over the past few years, timber and livestock producers have faced depressed commodity prices and volatility due to fluctuating demand and exchange rates, pest outbreaks, and regulatory changes.  Additionally, the mountain pine beetle epidemic has created unprecedented social and economic challenges for communities in the region.  As part of a toolkit to address sustainable diversification, agroforestry systems such as silvopasture can help agricultural producers respond to these socio-economic and resource management challenges.

The Cariboo silvopasture demonstration at the Zirnhelt Ranch is an operational agroforestry approach implemented on a recently timber-harvested site and managed under high-intensity, short-duration grazing.  The long-term objectives of this demo are to determine the integrated forage and timber production, soil moisture response and the economic cost-benefits of a silvopasture approach under these conditions.

Bale grazing to help reduce unwanted brush

Establishing the silvopasture has involved brushing of unwanted shrub and tree regeneration, fencing and water developments.  And the Ranch has utilized innovative, low-cost methods to implement the silvopasture treatments with an eye towards short and long-term profitability.  For example, winter feeding of cattle over the untreated forest regeneration successfully reduced brush without damage to crop trees and created better conditions for grass and forb production.

In other areas, a silvicultural contractor spaced crop trees (a mix of fir, pine, spruce, aspen and birch) and a crew of three hand-piled the slash for later burning.  Zirnhelt Ranch bought this land after the trees had been harvested, and it was a full nine years post harvest before the silvopastures were implemented.  Ideally, for silvopastures created through logging and brushing, early introduction of cattle after logging, and in sufficient numbers to have a desired landscaping effect of trampling and stirring up the soil surface, to facilitate seeded forage establishment.

Thinning and piling to create a silvopasture

In the grazing season, cattle are used for additional brush control through their browsing.  The native shrubs that dominate the site have enough nutritional value for maintenance, but not large weight gains.  The silvopasture therefore has limits for backgrounding or finishing cattle at least in early years of development.

The Ranch has found temporary electric fencing (multi-strand electric wire and step-in posts) ideal for the silvopasture.  Major subdivision of pastures were created by running permanent cross fences from the top of the hills to the bottom, which allowed additional temporary fencing to be installed for frequent (daily to weekly) moves of livestock to follow the contours of the land.  They also found  that for any water supply it is a good idea to have a permanent electric mainline close by so that the water source can be enclosed with a charged (hot) fence to protect the water developments from excess trampling.  Locating permanent subdivision fences and travel corridors close to the water supplies is important in keeping maintenance costs down.