As I walk around some of our pastures, I wonder and try to observe what is going on with the plant communities. I also watch the cattle and try to identify what they are eating.
In my case, I am looking for what I consider the most nutritious plants for the cattle but I also look for sign of a healthy plant community. Hopefully well managed pastures will be balanced in the healthiness for cattle (or other livestock) and a healthy ecology.
As I put questions to myself, more often than not I realize I don’t know the answers. My baseline for any conclusion from looking at the pasture (grasses, forbs, shrubs and trees) is that I want to see a semi open landscape.
Some have said that as human beings evolving, we sought for our habitation a balance of openness to see predators and cover to protect us from the elements. Science tells us we evolved as a species in the Savannah which is dominated by grassy areas with few trees.
Recently, more consideration has been given to having trees for shade, shelter, deep rooting for water conservation, and the spreading of nutrients by falling leaves. This fertilization has the effect of bringing up nutrients for the plants growing close to the surface of the soil.
If we want trees and shrubs as part of the pasture for biodiversity purposes, then we must ensure the grazing animals don’t negatively impact them to the point of elimination.
Too little impact on trees in-growing in grasslands and especially in wetter regions will result in tree canopy closure leaving little or no light for grasses and forbs and maybe shrubs that make good grazing feed.
Fire used to play a much bigger role in keeping the forest in check for the sake of the open land species that humans have wanted.
For those readers who want to know more depth about research on this topic, I would direct you to the Noble Research Institute.
The Nobel Research Institute is an independent non-profit agricultural research organization based in the US dedicated to delivering solutions to great agricultural challenges. Their website is www.noble.org.
The complexity of good management can be seen in the June 2020 blog available at their website.
Put simply to make better decisions on the ranch we must understand the eight grazing metrics.
The five foundational metrics are: stocking rate, carrying capacity, annual demand and animal units, allowable forage and harvest efficiency, grazable acres.
Then there are the three metrics of management tools: stock density, grazing days per pasture, and stock days per pasture.
The best Canadian resource is, as I have cited before, the Beef Council Research Council.
Good intensive managers must try to improve their understanding of all of these metrics and use them.
For me this is a work in progress. Right now, I am hoping to reduce ingrowth of brush and too many trees by targeting areas where the aspens are springing up and the hazel brush is dense.
I see the cows, who also love peavine and grasses, nibbling at wild roses, alder brush, young aspens, …the list goes on. This is the season of greatest palatability of these non-grass species.
I will also be watching for overgrazing which can damage the “desirable” species of grasses.
Complicated and challenging!
David Zirnhelt is a rancher and member of the Cariboo Cattlemen’s Association. He is also chair of the Advisory Committee for the Applied Sustainable Ranching Program at Thompson Rivers University Williams Lake.