As we move into the dry season on our annual rangelands, I thought it might be useful to post a few resources on feeding supplemental protein to livestock to maintain forage intake!
Annual Rangeland Forage Quality (UCANR Publication 8022) - this 2001 publication provides a useful overview of the seasonal and annual variation in forage quality in our foothill region.
Cow Supplementation: Getting the Best Bang for your Buck (Proceedings, The Range Beef Cow Symposium XXIV, by K.C. Olson, 2015) - this is a great overview of ruminant nutrition and supplementation strategies, along with some basic economic considerations.
Alternative Protein Supplementation (Sierra Foothill Research and Extension Center Drought Workshop, 2014) - this video of a talk by Dr. Roberto Sainz from UC Davis offers some interesting alternatives to rangeland protein supplementation.
Essential Nutrient Requirements of Sheep (New Mexico State University) - a useful overview of sheep nutritional requirements, including protein supplementation strategies.
Every spring, there comes a stretch of time when I wish we had 10 times as many sheep. Since we're stocked at a level where we're comfortable we'll have enough grass in bad years (and in the autumn months - see my December 2018 post, Fall Feed... or Fuel Load?), we almost always have more grass than grazers in April and May. We simply can't keep up with forage growth during the spring flush.
Grazing, obviously, can be a tremendous tool for managing fuel load (especially "fine" fuels, like grass and broadleaf plants) in our Mediterranean climate. Unlike mowing or mechanical fuel reduction tools, or herbicide treatment, grazing actually removes flammable material - ruminant animals like sheep, goats and cattle convert this "fuel" into muscle, fat, bone, and fiber. Grazing livestock can access areas where it would be next to impossible to operate equipment. And areas that have been grazed don't burn with as much intensity as areas that haven't.
Despite these benefits, every spring I am reminded that we simply don't have enough livestock in California to address all of our wildfire fuel problems. Targeted grazing contractors have developed successful business models focused on bringing grazing animals to the fuel load - working with utilities, homeowners associations (HOAs), and municipalities to manage fuels near infrastructure, residences, and communities. Yet even within these more focused operations, I believe we'd benefit from greater coordination between grazing contractors, rangeland managers, and fire planners. Let me explain using an example from my own spring/summer grazing operations.
We no longer operate a paid targeted grazing business, but we do trade winter grazing for summer fuel load reduction with a community near Auburn - in other words, we graze our sheep in the community during winter and early spring for free, in exchange for reducing fuel load in the late spring and summer. So far, this arrangement has worked well for us as well as for the HOA. We do a great deal of grazing planning during our lambing season (mostly to ensure that we've got enough forage and natural shelter for the ewes and lambs); more recently, we've also started to be more intentional about our summer grazing plans.
The fuels in this community are mostly annual grasses and broadleaf plants, with some coyote bush, poison oak, and Himalayan blackberry interspersed with blue oaks, interior live oaks, and foothill pines. The homesites are located on a series of parallel ridges and drainages that fall off to the northwest, and the community is adjacent to a large regional park. In thinking about our summer efforts to make this community more fire safe, we've chosen to remove fuels from a strip on either side of the roads and driveways serving the homes. We've also grazed around the structures that are situated on ridge tops. We've realized that our grazing wouldn't necessarily be a fuel break (in the sense of removing all vegetation down to mineral soil); our grazing, rather, would hopefully slow a fire enough to give fire fighters a chance to protect structures and lives.
As we've thought about this, however, I've realized that I would benefit from a better understanding of fire behavior in our particular environment. Where are the ignition sources likely to be? My sense is that southerly Delta breezes in the summertime are usually associated with lower temperatures and higher humidity (and less extreme fire behavior). North and northeast winds, on the other hand, tend to be hot and dry - does this suggest that we should focus our grazing on removing fuels north and east of the community. These kinds questions, I think, are where ranchers, rangeland managers, and fire planners could greatly benefit one another's understanding of these interactions. Since we can't possibly have enough grazing animals to address ALL of our fuel-load issues, we need to be more strategic about prioritizing grazing activities that are focused on fuel-load reduction. These kinds of collaborative efforts, I think, are an important piece of reducing the threat of wildfire in our foothill communities.
As a grazer of sheep, at least from a forage management perspective, I live by the rule, "If the worst might happen, it probably will." A corollary to this rule is that pessimists are often pleasantly surprised. As a somewhat pessimistic rancher, I'm pleasantly surprised when we get fall rains and green grass before Halloween!
My pessimism manifests itself in a variety of ways. Like many ranchers, one of my go-to drought preparation tools is to use a conservative stocking rate. We maintain the number of animals that we know can graze even in a dry year, rather than permanently stocking for the best years. We can always adjust our stocking rate up when we have lots of grass (by purchasing feeder lambs or grazing someone else's sheep). This also means that we save some of the grass that grows each spring to come back to in the fall - this dry forage is the buffer that ensures we can carry our livestock through until the grass starts to grow again.
But this dry forage can represent a fire hazard in the summer and early autumn months. By consuming grass, broadleaf plants and brush, grazing and browsing livestock can help reduce fire risk by removing or modifying these fine fuels. For some, biomass utilization conjures images of high-tech power plants utilizing wood chips to generate electricity; for me, biomass utilization means that livestock eat plants; plants that might otherwise burn in the summer and fall.
These differing perspectives on the value of (or threat from) dry forage set up potential conflicts between grazing tenants and grazing landlords. The tenant, by necessity, wants to save grass for fall (a "non-rainy day" fund of sorts); the landlord wants to reduce fire danger. How do we meet the needs of both parties?
I'm not certain that I've figured out the answer to this conundrum, but perhaps our experience in managing our sheep this summer and fall might shed some light on one approach. After talking with the community that owns our winter grazing land, we weaned our lambs 3-4 weeks earlier than normal so that we could move ewes back to dry forage (dry ewes have significantly lower nutritional demands than lactating ewes or growing lambs). With input from the homeowners, we focused our summer grazing on the most vulnerable areas - south-facing slopes adjacent to homes, roadsides where fires could start, and weed-infested areas that needed summer grazing impact.
A careful accounting of our year suggests that our efforts, while beneficial to the neighborhood, were costly to us. Our early-weaned lambs were lighter than usual when we sold them, which meant lower income. Our replacement ewe lambs haven't grown as well as we expected. Our ewes needed supplemental protein (to allow them to digest dry grass) for 3-4 weeks longer than normal, which meant higher expenses. In other words, it cost us money to manage someone else's fuel loading problem.
These economic impacts are even more pronounced for cattle producers. Since sheep and goats have much shorter gestation periods, we typically have a 2-3 month window where their nutritional requirements are quite low - we can push them to manage dry forage and not impact next year's lamb or kid crop. Cattle, on the other hand, must re-breed 85-90 days after they deliver their calf - which makes nutrition between this year's calving and breeding for next year's calf crop a much more critical consideration.
Timing is also critical. In my experience, the critical time for reducing fuel loads with grazing is late spring and early summer - after the last rain but before the forage becomes tender dry. In reality, this means we need to cover lots of ground in a 4-6 week period - and few of us have enough livestock at that point in the grazing year to move that quickly. The challenge is further complicated by the fact that our annual grasses are less palatable at this growth stage.
Ultimately, grazing can be an incredibly important tool in reducing fire danger in our Mediterranean climate. Using this tool effectively, however, has value (and costs) - just like any other fuel-load reduction tool. As a rancher, I want to make sure I have some dry grass to come back to in the fall. This doesn't solve the fuel-loading problem; my community's fuel load is my fall forage. We need to re-think our grazing arrangements to reflect this reality!
April 27-28, 2018
UC Sierra Foothill Research and Extension Center
8279 Scott Forbes Rd., Browns Valley, California
This two-day, hands-on grazing school will provide participants with practical, field-based experience in applying the principles of managed grazing on rangeland and irrigated pasture. Working in teams, participants will learn about grazing planning, paddock design, range ecology, estimating carrying capacity, range ecology and monitoring, and drought planning.
Day 1 (Friday, April 27 - 8:30 a.m. - 7 p.m.)
- Principles of Managed Grazing
- Stocking Rate and Carrying Capacity Field Activity
- Electric Fencing Basics Field Activity
- Practical Grazing Management Field Activity
- Range Ecology and Monitoring
- Feed Budgeting and Drought Planning
Day 2 (Saturday, April 28 - 8:00 a.m. - 4:30 p.m.)
- Nutrition and Supplementation
- Pasture Walk and Assessment
- Beef Cattle Economics 101
- Putting the Principles into Practice - Action Planning for Your Ranch
Cost: $180 (includes meals and course materials). No refunds - your payment guarantees your space!
Hotels are available in Grass Valley and Marysville. Dormitory and camping spaces are available on a first-come-first-served basis at SFREC.
For more information:
Researchers at the UC Sierra Foothill Research and Extension Center (SFREC) in Browns Valley have been collecting rangeland forage production data since 1979. As a rangeland geek, grazier, and now livestock farm advisor, I find it fascinating to look back at the tremendous variability in forage growth over the last 39 years - partly, I suppose, to help predict the short-term future (in other words, this year's spring growth). From a practical standpoint, I find this dataset helpful for grazing planning purposes, as well.
Since the beginning, SFREC staff has noted germination dates for each year. Since the mid 1990s, the staff has also measured total available rangeland forage on the first day of the month from December through peak standing crop (which generally occurs sometime in May or early June). The average germination date over that time is October 21 - although germination has occurred as early as September 2 (in 2000) and as late as December 12 (in 2002). Interestingly, total production was right at average in 2000-2001, while the much later germination year (2002-2003) produced 145% of normal forage. Timing of precipitation after germination seems to be a critical factor!
As I said at the outset, annual rangeland forage production is incredibly variable. Total production over the last 39 years has ranged from 1,071 pounds of dry matter per acre in 1987-88 to 4,696 pounds per acre in 1992-93. Monthly production is also all over the board - on February 1, 2014, the crew measured just 98 pounds of dry matter per acre (average for the date is 533 pounds). I remember that February well - my family and I sold about a third of our commercial ewes because we simply didn't have enough grass.
Forage production on annual rangeland, obviously, is tied to precipitation. The relationship, however, is complex. Total precipitation is probably not as important as the timing. Air and soil temperatures are also related to grass growth, as this year's numbers clearly demonstrate. Here in Auburn (and I suspect in Browns Valley), our seasonal rainfall has been up and down. We had good rains in November, a relatively dry and warm December, a wet and warm January, and through this week, a dry February. As of today, our precipitation is about 80 percent of normal for our part of the foothills. This year's February 1 forage production at SFREC was a whopping 957 pounds of dry matter per acre - nearly 180 percent of normal for the date. And to think that back in late December I was worried about having enough grass this spring!
The timing of moisture also impacts the date at which we reach peak standing crop. With the dry weather and north wind we've had up until this week, I wondered if our annual grasses would mature earlier than normal. Antecdotally, some of the lower elevation ranchers I've spoken with in the last several weeks reported that the grasses on their shallower soils were starting to show signs of heading out. And talking to friends who ranch in other parts of the state (especially the Central and South Coasts and the San Joaquin Valley), the grass in our Sierra foothills is the exception rather than the rule this year. Some parts of the state do not have any green forage at all.
So what can we do with these numbers from a practical standpoint? I use the monthly numbers for planning purposes - a dry, cold autumn followed by a dry December and January means we'll be tight on forage in February (like 2013-14). Conversely, adequate moisture and warmer-than-usual temperatures (like last year and, at least in our region, this year) means extra forage in February. I also use the peak standing crop information to plan for summer and fall grazing. If we know how much we've grown, we can ration out our dry forage and make sure we leave enough residual to protect the soil when the rains start again in the fall.
Experienced ranchers, obviously, know the difference between a good grass year and a poor one. The data collected at SFREC helps put numbers to this variation - numbers that can help all of us become better managers!