Sunday, July 24, 2016

Adaptation and Resilience

I'm taking a course as part of my master's degree program at Colorado State University called "Managing for Ecosystem Sustainability."  I've enjoyed the course, which has covered topics like the carbon and nitrogen cycles and soils management.  The reading materials and lectures have also focused on resiliency and adaptation to climate change - topics that are especially relevant to me, given my recent experience with drought.

I've long thought that any successful response to climate change will require an accumulation of small, individual decisions to change our behaviors as a species.  Government mandates and technological advances aside, climate change will only be addressed successfully by individuals, in my opinion.  The "big" solution doesn't seem likely.  In the past, my thinking has focused on behavior changes that will reduce, or at least slow, the affects of climate change (increasing carbon dioxide concentrations and temperatures and rising sea levels, just to name the ones that come to mind immediately).  This class, on the other hand, has made me consider the things that I can do personally to adapt to these changes (which, increasingly, seem inevitable to me).

In some respects, the long history of agriculture has been one of adaptation.  Farmers and ranchers have figured out what grows well in their specific location.  In California, at least, crops are grown (for the most part) where the climate and environment support their profitable cultivation.  Rice is grown on heavy soils in the Sacramento Valley, for example.  Small grains (wheat, barley, rye, etc.) are grown in the Montezuma Hills in the Delta where irrigation water is scarce.  Avocados and citrus are grown in climates (and micro-climates) where freezing temperatures are unlikely.

Ranchers make similar choices.  In his essay, "Let the Farm Judge," Wendell Berry writes about the powers of observation and adaptation that led British (and Scottish, Welsh and Irish) shepherds to develop 80 distinct breeds and cross-breeds of sheep on a group of islands the size of Kentucky.  As Berry suggests, while the market (consumer demand) often places specific product demands on livestock producers, the land and its climate deserve at least equal weight in a producer's decisions about livestock breeds.

 Admittedly, sometimes technology gets it wrong.  I'm not convinced - the economic incentives aside - that we should be growing almond trees on rangeland in California (for a variety of reasons).  As the grain farmers who broke the sod of the high plains in the 1920s learned, rain doesn't follow the plow.  I guess this brings me back to the importance of individual acts over large-scale technological innovation.

Our ranching operation entails turning grass (grown on rangeland that won't - or shouldn't - produce cultivated crops) into flesh and fiber and milk.  Using ruminant animals (sheep, in our case), we turn this grass into products that humans can use.  We've focused on sheep because we feel that they fit our environment (small pieces of unfenced grassland) better than cattle (and frankly, because sheep fit my skill-set better than cattle).  We've focused on a cross-breeding system that results in sheep that thrive on a combination of annual grasses, weeds, brush, and irrigated pasture.  And we've selected individual sheep in our breeding program that perform especially well in our oak woodland environment.

Rising temperatures and increasing carbon dioxide concentrations will undoubtedly impact our rangelands and our irrigated pastures.  I expect that we'll see more invasive weeds (both grasses and broadleaf plants).  We'll see warm-season grasses (which thrive with more carbon dioxide and warmer temperatures) displace the cool-season grasses in our irrigated pastures.  Because sheep generally have a more widely varied diet than cattle - and because our sheep specifically have been exposed to a wide range of forage plants - I think we're well positioned to adapt to the changing climate.

Some "experts" believe that animal agriculture should be abandoned in the face of climate change - after all, ruminant animals emit methane (a far more potent greenhouse gas than carbon dioxide).  I disagree for a variety of reasons.  First, grazing animals allow humans to produce nutritionally dense food (meat and milk) and renewable fiber on land that won't grow a crop.  For example, our ewes spend approximately two thirds of the year grazing on land that is too dry, too steep or too poor to grow a food crop - but this land grows outstanding forage (which our sheep convert to meat and wool).  Second, by focusing on the type of animal that fits our environment - and managing our rangeland to favor the plants that they prefer - we can increase the digestive efficiency of our sheep (and reduce methane emissions).

I'll admit that I'm worried about the world we seem to be leaving our children and grandchildren.  As I write this piece, we're in the midst of our second significant heat wave of the summer in Northern California.  While I'm not suggesting that this (or any particular) heat wave is a result of global climate change, I do worry about the ramifications of even a small increase in average temperatures.  That said, I'm encouraged by the proven ability of farmers and ranchers to adapt to their environments.  Taking steps to reduce the drivers of climate change is important; continuing to adapt to an ever-changing environment is even more critical.

Thursday, July 7, 2016

Managing the Dry Season

As we enter the middle of summer in the Sierra foothills, we transition to a different phase of our annual grazing management.  Our lambs are making one last pass over our irrigated pasture, while the ewes have been moved onto un-irrigated annual grasslands nearby.  With the rains of last winter and spring behind us, we're meting out this year's forage growth (in the form of standing dry grass and broad-leaf plants) - and hoping for a few soaking rains in October to get next year's grass started!

Sheep are ruminant animals, which means they have multiple compartments to their digestive tract.  Micro-organisms in the rumen (and to a lesser extent, in the omasum, abomasum and reticulum) allow ruminant animals to break down cellulose (plant fiber) into essential fatty acids.  In other words, the bugs in a sheep's gut allow the animal to make a living on grass!

To facilitate the digestion of cellulose, these micro-organisms require the animal to consume forages or other feeds with at least 8 percent protein - the bugs need the protein to survive.  On our annual rangelands, green forage typically contains 15-25 percent protein.  During the growing season (fall, if we get rain, and especially springtime), the standing forage contains more than enough protein - indeed, this is why we lamb in late winter and early spring.  But during the dry months (mid-June through October or November, typically), our dry annual grasses and broad-leaf plants are very low in protein (as low as 3-4 percent).  Despite the decline in quantity, we typically have more than enough quantity of forage during these months.  The trick for us, then, is to get enough protein to the sheep to allow their "bugs" to digest this dry forage.

The most important part of our grazing/nutritional strategy is timing.  We time our production cycle to take advantage of the usually sufficient quantity of high quality forage in the spring time - we match demand with supply.  The greatest nutritional demand for a ewe is during her last month of pregnancy and her first six weeks of lactation.  By overlaying this 10-week period of high demand with the period of rapid grass growth in the spring, we eliminate the need for supplemental feeding during this critical time.  Equally as important, this schedule allows us to match our period of lowest demand (post-weaning and pre-breeding) with the period of lowest forage quality.

After we wean the lambs and before we start preparing the ewes for the next breeding season (a technique called "flushing" - more on this below), we simply want the ewes to maintain their condition.  Actually, for the 7-10 days after we wean the lambs, we like to have the ewes on low quality forage to dry up their milk production as quickly as possible (which reduces the chance of mastitis).  During this maintenance phase, we put our "dry" ewes (dry, as in no longer producing milk) on our dry annual grass.  To make sure they can digest this dry forage, we also provide supplemental protein.  Over the years, we've tried a variety of supplements - from alfalfa hay to molasses-based protein tubs.  Currently, we've provided tubs with 18 percent protein to the ewes; next week, we're going to try a small quantity of barley screenings (12 percent protein) fed by hand every other day instead of the tubs.  The grain won't replace the dry grass in our ewes' diets; rather, it will provide their gut micro-organisms with enough protein to digest the grass they'll will be grazing.  If it works, it will be a much lower cost alternative to the protein tubs.

If we had more irrigated pasture, we'd graze the ewes on green forage during the mid-summer months.  However, with our current limited pasture availability, supplemental protein allows us to keep more ewes in our flock to take advantage of the green grass in the winter and spring (and to make our business economically feasible).  Supplemental protein also allows us to use our sheep to help reduce the fuel load in our community - the ewes are currently reducing the fire danger in a neighborhood adjacent to Hidden Falls Regional Park west of Auburn.  Once the lambs have made their second pass over the irrigated pasture, they will either be sold or moved to dry forage as well (with supplemental protein).

The lower quality dry forage we're currently grazing also makes the effect of flushing more pronounced.  In early September, we'll move the ewes back to our irrigated pastures (which will have been ungrazed for 50-75 days at that point).  We'll also hand-feed the sheep with a high-protein, high-energy feed (this year, we'll use pelleted canola meal).  The shift from low-quality dry grass to higher-quality green grass and supplemental feed will increase ovulation in the ewes - and give us more lambs next spring!

In the meantime, our summer days are spent moving water on our irrigated pastures and building fence on our hard, dry annual rangelands.  We check the dogs (guardian dogs and border collies alike) and our socks for stickers and burs.  We watch the horizon for smoke and the sky for fire planes (wildfire is a constant worry during our summer grazing season). We lug 125-pound protein tubs or buckets of grain to the ewes.  And we look forward to the first rains of autumn!

Saturday, July 2, 2016

The Scariest Weekend of the Year

I awoke this morning to the realization that it was time for me to write my annual plea regarding fireworks and the 4th of July (see Living with Wildfire or Nervous).  As I write this post, significant portions of California are on fire - and our wildfire season has only just begun.  Closest to home, the Trailhead Fire has consumed more than 3,000 acres about 15 miles east of our home.

I'll admit that I enjoy a good, professionally orchestrated fireworks show.  For several years now, my family has gone to see the Sacramento River Cats play baseball on July 3 - both because we enjoy baseball and because the team puts on an outstanding fireworks display.  But living in the foothills - and running sheep on annual grasslands (which are tinder dry by this time of year) makes me nervous around Independence Day.  One careless spark could mean disaster.

And so here's my plea: if you live in the Sierra foothills and you want to enjoy fireworks, please (PLEASE) go somewhere and watch a professional show.  Don't take a chance on starting a fire!