Grass just grows with a little water and sunlight right? Carbohydrates are created by photosynthesis working with minerals from the soil.
Not so simple, but if you want to now more check out this reference that was recently provided to the students of the Applied Sustainable Ranching Program at TRU by the instructor, Dan Denesiuk, for two modules of the Environmental Sustainabliity course during the past week.
This online course, located at www.plantsciences.ucdavis.edu/gmcourse/module_resources/module1/resources/howgrassgrows.swf, is a great short primer. We learn that there are three basic factors that we can manage with respect to grazing. First, the frequency, is the number of times a plant is defoliated during a period of time. Second, intensity, the proportional removal of plant material.
Third, the opportunity for growth and/or regrowth (timing or season) determined by environmental factors, season of removal, previous defoliation events, frequency and intensity.
The conclusion from the chart shown is that if you want your pasture plants to keep growing, you can’t allow your grazing animals to eat more than 50 per cent of the leaves, or the ability to recover the growth is seriously compromised and regrowth won’t happen for a month or so rather than immediately regrowing.
If you cut hay and set the cutter bar at eight inches rather than the typical four inches above the ground, the plants will recover faster. Similarly, the old rule of leaving stubble height at four inches when you move the livestock, probably is really outdated. Yet the West, they say, was built on this paradigm.
The Western rangelands won’t be sustained with this practice of taking more than 50 per cent of the leave matter.
Now don’t take it from me. You will have a chance to hear three experts and the subject of plant growth and range management.
They are going to be at Thompson Rivers University on June 24, in two weeks at the Williams Lake campus. They will be wrapping up this subject with the students, first with a classroom session and then a field trip. Cost to attend this seminar is $80. This is a highly subsidized cost.
TRU has money from industry funding sources on the condition that there be contributions by those attending. In my view, this is good value.
Lauch Fraser, professor from Kamloops who has headed a lot of research on Carbon sequestration will be there with one of his students (Dan Denesiuk, mentioned above) who has sampled soils and grasses in pastures in the Cariboo/Chilcotin and elsewhere.
The third speaker is Allen Dobb, a well-respected agrologist who has recently written The Rangeland Seeding Manual. He has been doing work in the Cariboo on ground water supply, wildfire management, storage dams for agriculture and land claim settlements.
Come and learn more. We are bringing this opportunity close to home.
David Zirnhelt is a member of the Cariboo Cattlemen’s Association and chair of the advisory committee for the Applied Sustainable Ranching program which started at Thompson Rivers University in Williams Lake this January.