Note: This post was adapted from my Foothill Agrarian blog.
I've read a number of Twitter threads over the last six weeks that have been focused on supporting local farmers and ranchers during the COVID-19 crisis. I think this is great! Anything that refocuses our food buying habits on local producers is positive, in my opinion. But even at the local level, our food system is a complex network of relationships, business and otherwise. And producing meat, especially pork, lamb, and beef, is even more complicated - by regulations, as well as by basic biology. I thought it might be useful to walk through my own decision-making process when it comes to how we market our lambs.
Fundamentally, we are in the business of harvesting grass and other vegetation with sheep. Through the miracle of rumination, our sheep are able to turn this forage into muscle, fat, bone, fiber, and milk. When it comes right down to it, we're in the business of turning the products of photosynthesis into meat and wool.
As ranchers know, not all grass (or broadleaf forages) are created equal - nor are they of equal nutritional value all through the year. As grazers, we must be concerned with both quantity and quality when it comes to creating an annual forage budget. And we must think about matching our production cycle with our forage availability - in other words, we need to balance supply and demand.
From a quantitative perspective, we have an abundance of green, nutritious forage (in most years) from March through mid-May on our unirrigated rangelands, and from April through late June on our irrigated pasture. After the "summer slump" (when temperatures are too warm for our cool-season forages like orchard grass and clover), we get a second (although lesser) peak in forge production in the late summer and early fall. The most challenging time for us here in the Sierra foothills and Sacramento Valley is mid-autumn through mid-winter - in Auburn, our irrigation water ends on October 15, so we must conserve last year's dead grass until the autumn rains germinate the forage on our annual rangelands.
In terms of quality, we focus largely on protein. The rumen microbes that break down cellulose and provide our animals with energy need at least 7-8 percent protein in the forage the sheep are consuming. Green forage is much higher in protein (typically) than dry grass - the forages on our annual rangelands and irrigated pastures right now (late April) are 14-20 percent protein; the dry grass that our ewes graze in July and August are 4-6 percent protein.
On the demand side of the equation, our forage demand (both in terms of quality and quantity) peaks as our ewes give birth and nurse their lambs. Non-lactating ewes have much lower feed demands - that's why we can graze them on dry annual grass in mid-summer. Growing lambs, on the other hand, need the most nutritious forage we can provide - they need energy and protein to grow muscle, bone, fat, and wool. Since we wean our lambs in mid-June at 65-70 pounds, this means that any lambs we plan to keep and finish on grass (at 100-110 pounds) need the highest quality forage we can grow. And we have a second (albeit) lower peak in nutritional demand in September, when we bring our ewes back to irrigated pasture to get them ready for breeding season.
Regardless of the forage type (green or dry rangeland forage or irrigated forage), we boil the considerations I've outlined into an estimate of sheep days per acre. This is sheepherder talk for estimating how many sheep one acre of forage will support for one day (cattle producers can do the same kind of estimate - one cow day's worth of forage will feed 5-6 sheep!).
Last summer, we grew (and harvested with sheep) just over 18,000 sheep days of irrigated pasture forage. If we divide this number by the days in our irrigation season (180 days, to keep the math simple), we see that we can graze 100 head of sheep on our pasture for the duration of the irrigation season. Let's break this down a bit further:
- From April 15 to June 15, we grazed 80 lactating ewes, 10 replacement ewes, and 110 lambs on our irrigated pasture. Based on how much each of these classes of animals consume, we estimate that we harvested about 9,000 sheep days in that two-month period.
- Once we weaned the lambs, we sold all but 35 of them (the sheep we kept included 20 replacement ewe lambs and 15 feeder lambs that we wanted to finish on grass). These sheep remained on irrigated pasture from June 15 through August 31 (for our purposes, let's say 75 days). These sheep consumed 2,625 sheep days worth of forage.
- From September 1 through the end of irrigation season on October 15, we had all of our sheep (ewes, replacement ewe lambs, and feeder lambs) on irrigated pasture - a total of 120 head. During this period, we harvested another 5,400 sheep days of forage.
- After the end of irrigation season, we had approximately 975 sheep days of forage left - with 120 head of sheep in our flock, this meant we had just over 8 days of grazing left on our irrigated pasture after the water turned off.
So how did a blog post about selling meat end up looking at grazing math?! Let's say that we wanted to direct market more lamb as individual cuts of meat (that is, finished and processed lamb). For example, what if we wanted to finish and direct market 75 lambs - could we do it with our current forage resources? From June 15 through the end of irrigation season, these 75 lambs would require 9,000 sheep days of our best forage. Since we'd already used 9,000 sheep days up to June 15, these lambs would require every blade of grass we could grow after weaning. We would have no grass for growing ewe lambs, nor would we have any grass for our breeding ewes. Our alternatives would be to purchase hay, lease additional irrigated pasture, or reduce the size of our breeding flock. We couldn't simply wake up on June 15 (weaning day) and decide to keep 60 extra lambs because we wanted to sell meat next November instead of feeder lambs next week.
The last issue for me is the added time and cost involved in marketing meat. In a good year, I know I can sell our feeder lambs in late June for $130-150 per head. If I decide to finish them and sell them as meat, I will incur additional costs beyond the cost of feeding these lambs for another 4-5 months. Once they're finished, it will cost me about $150 per lamb to have them harvested and packaged in a form that I can legally sell. I'll have multiple trips to the processor (which take me away from doing work on the ranch). I'll have the time involved in marketing and selling meat (which can be significant). I'll have the cost involved in storing meat. At our scale, I've found that selling meat results in higher gross income, but selling feeder lambs in June results in higher net income. In other words, we're more profitable selling a live feeder lamb in June that we would be selling meat in November.