Today I read a draft chapter in the master's thesis of my friend and future colleague, Grace Woodmansee. Her thesis explores the drought management strategies of California ranchers, and without giving away her work, I want to share something I learned from reading her thesis: Since 2000, our weather in California has been trending drier. Looking at my own weather records (which date to 2002), I can see a great deal of variability in our precipitation timing and quantity. For our sheep operation, one of the most critical dates is the first real rain of autumn - the rain that gets our grass started. The rain we still haven't received as I write this blog post.
The UC Sierra Foothill Research and Extension Center has kept weather and forage records for about 40 years. Over that timeframe, the average date of a germinating rain is October 21. Looking at the last 19 Octobers in my records, we've received a germinating rain just less than half the time - proving that the average (or more accurately, the median) is simply a number where half the data lies on either side.
Variability is a fact of life when you're working with nature, and our approach to raising sheep reflects this uncertainty. We stock our rangelands and pastures conservatively. We time our high forage demand periods with the rapid growth phase on our rangelands. We try to leave enough forage at the end of the spring flush of growth that we'll have some dry forage to return to in a fall like this one. And we plan - we look at our forage availability and demand during key periods (like post-breeding in the late fall and lambing in the late winter and early spring).
For example, we are wrapping up our 6-week breeding season this week. During the first 6 weeks of gestation, our ewes have fairly low nutritional demands - which means we can utilize the dry forage we saved, as long as we provide supplemental protein. This year, we've penciled out the various sources of protein (including alfalfa hay, protein tubs, and loose bagged protein) and determined that alfalfa is our most economical option (at $7 per day). We'll feed hay every other day until our rangelands have grown enough green grass to supply the needed nutrients. We've also carefully mapped out the forage remaining on our irrigated pastures; every day on this still-green forage will delay the onset of feeding hay (and save our dry forage).
Having ranched through the millennial drought of 2012-2016 (the driest stretch of years in California in the last 12 centuries), my perspective on drought management has evolved. We still don't plan on feeding our way out of drought (that is, entirely replacing standing grass with hay), but we will chose economically feasible supplementation options. We won't pregnancy scan our ewes so that we can sell anything that isn't bred - rather, we've done a better job of matching our stocking rate (demand) with the carrying capacity (supply) of our winter rangeland. On the other hand, we've stopped giving ewes a second chance - if there's a reason to cull a ewe (because she didn't have a lamb or she's missing some teeth), she's gone!
Drought, in some respects, is similar to the pandemic we're living through. The beginning of a drought can sneak up on us, and we don't know when it will end. I've joked recently that I'll believe in a forecast of rain when I actually walk outside and get wet. And I'll believe we're not in a drought when I look back on the rainy season and see "normal" precipitation. Perhaps that's always been the way of ranching - perhaps "normal" has always meant the flexibility to survive the abnormal!
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