Often we are asked the question, "How big are your pastures, how many do you have, and why not make them smaller?" In order to answer this one must understand some background in regards to our location and our personal experiences as they are the determining factors to our pasture managament. First, our ranch is located in the heart of the Chihuahaun desert in Northern Mexico. According to the jornada experimental range in New Mexico, the average precipitation for our area is 255mm (10 inches) per year. In my own opinion, there is no such thing as an average. As we have seen, we might receive all of our annual precipitation at once, none at all or in a lucky year consistently and effectively throughout the monsoon season. From our observations we can typically rely on having two good years out of a whole decade. From 2010 to 2013 we recived a total cumulative rainfall of 280 mm, less than 100mm (4 inches) per year. At the end of the drought, summer of 2013, we received 320mm (13 inches) in a single week, then nothing more for the rest of the year. Ask yourself if it is even possible to mantain your herd with those conditions in small pastures? Is it practical to plan for a three year rest period, as this is what nature gave us to work with? To our surprise it was possible to survive the three year drought but it took a lot of thinking outside the box. Obviously we had to destock more than 60% of the herd. We did it gradually as things got worse and this helped from a cashflow perspective instead of selling all at once. Secondly, we had to rotate pastures as many times necesary to stay alive. Our thoughts in doing so was to provide any available forage and seasonal growth to keep our animals and pastures in the best possible condition.
Here are a few more details about our operation that aid in pasture management decisions. Our goal is to graze or introduce our cattle to areas they have never been before within our large pastures. Second, we manage only one group of animals which makes movements and planning easier. Also, by default you increase your rest time in all pastures. This also means that we do not have a controlled breeding season but rather, allow nature to determine when the best time to calve is. Next, we try to take advantage of every single growth event be it herbs, flowers, weeds, mesquite blossoms and vines and if lucky all grass types both perennial and annual, and warm season and cool season. Each pasture responds differently to moisture, temperature and offers a variety of vegetation. Lastly, as tough as this might sound, only the strongest survive; not only cattle but also man. We attribute our ability to stay afloat in the worst of times to larger pasture sizes and the flexibility to use our pastures for multiple rotations a year. Droughts are cyclical and will absolutely continue thus we are not interested in changing anything about our pasture sizes. We feel they are necessary to get us through those moment where we might not see any growth for 4+ years.
One must remember that animal density is a human unit of measure, not an animal one. In our experience, we find that although our pastures are large and may not receive the density "people" think they need, we see good results in regard to animal impact. Cows don't stand fixed in a single spot but rather are constantly in search for the best possible nutrition and are social beings, always wondering. Just because we are unable to see them neatly packed doesn't mean they behave as such when we are not looking. Some may sleep together at night, others may fight or play momentarily, others my scratch or dig for dust to remove flies, ect. They are creating animal impact at all times. A larger pasture doesn't mean insufficient animal impact. What it does mean is that we have to manage them by staying only sufficient times. This leads me to the second question related in this complicated discussion.
Is it really necessary to implement high animal impact at all times? I've seen vast areas of my ranch that have been overgrazed for more than 300 years. Some of these areas still have zero response to high animal impact. On the contrary, there are other areas the cows do their job year after year without having to put forth any effort on my part. There are also parts that have mature, overgrown grass that could use the impact and needs to be trampled. Let's take a further look at these points. If I have vast areas that aren't getting much or any benefits from high animal impact or where progress is slow and often insufficient to support the daily nutritional needs of my herd, then why would it be necesary to divide into small pastures? Wouldn't it be better to leave a larger pasture that has all three of the above scenarios? Thus aiding in the experience of a "salad bar effect" for your cattle. Not to mention the other money saving aspects of not invest in more fencing and water, and just let the cows do the work. Plus, there is the added benefit that your cows may be more grateful in the sence they have more space to explore, socialize, and feed high quality forage in order to mantain animal condition and reproduce. Honestly, how would you like it if you had to live in a bus full of people and have to fight for your fair share of food your whole life? Wouldn't it be less stressful and more productive to know you have enough space and food? If your cows are running out of pasture and eating as if they were starving im sorry to tell you that is stressful and not natural. In some environments or irrigated pastures forcing your cattle to eat everything works fantastic and cattle are able to meet their nutritional requirements and remain in top condition. However, for those of us in a brittle, dry, erratic, drought prone area it is not a reliable practice in our humble opinion on a year around consistent basis. Every pasture change should look like a walk in the park.
Going back to an earlier comment about trampling old matter. Here is a question for you, "how often and to what extent is trampling really necessary?" Most of us, including myself, have been told it ALL must be trampled. Come to find out it doesn't, and I would strongly advise you not to. What if it doesnt rain for 2 years and you have trampled everything to the bottom and are left with nothing to graze? When managing with nature one must always ask these what ifs. Cows may not go to certain areas during a growing season leaving the grass to mature and in some cases oxidize. It has little nutritional benefit to cattle however, it is ground cover and protecting the soil from erosion and other hash elements such as the sun. In nature animals may not graze certain areas but they might go back later in the season or even a couple of years later. If you allow sufficient grass to remain in this state, cows will return when they desire and will trample it and may also eat a little. In the case of coarse desert grasses such as toboso once spring hits things tend to green up a little and provide cattle with higher protein. They will naturally go for the new green tender growth while also getting a mouth full of dry matter. This combination allows their rumen to digest the old and the roughage to prevent them from loosing up. Thus, achieving several benefits without needing to trample 100% of pasture production. One benifit that is nice on the pocketbook is not needing to supplement with a protein source to help digest old unpalatable grass. Also, if a drought hits at least there is sufficient standing grass reserves throughout the property. This will allow for numerous rotations and a good drought management plan. Trust me, if a drought hits by the end of it the whole ranch will be trampled. So if you are hung up on the idea of trampling everything, it will happen in time. My conclusion is not to want to trample everything all the time. Leaving grass behind is an insurance policy for all the what ifs and it allows the flexibility to move around the property in order to reach those areas that may provide alternative sources of food or seasonal sprouts of growth. During a normal growing season it is important to treat areas in need of further animal impact via herding or portable polywire. You might be surprised by then the cows may have done most of the job on their own.
So the big question, "What is the best pasture size?" I would say all of them. In my most productive areas it is best and most manageable to be slightly on the smaller side. The average of our smaller pastures is 200 acres. On the contrary in the less productive areas we tend to keep the pastures large. Our average size for our large pastures is 1,500 acres. There isn't a real definitive answer to this question. My biggest advice for those wanting an answer is to constantly be monitoring your cows condition, behavior and recovery time to breed back. The longer you wait to come back to a pasture, or the longer the recovery period than necessary, the greater the need to supplement to avoid loss in condition. If you observe closely your cows will tell you what is working or not. One last thing I discourage many folks about is going crazy with fencing. We have achieved the same if not better results with fewer pastures. It can be argued that fencing is not natural therefore the more fences you put up and pastures you create, the less in line you are with nature. And on a personal note, I hate getting of my horse to open gates. The other reason there is no real answer is because each property/ranch changes so drastically from the next. In fact, within our own ranch each pasture requires different management practices and attention every season. This is the reason I will not discuss the exact amount of days our herd stays in our pastures because this number changes every single time. Some pastures can support the whole herd for 3 days and others can hold them for 3 weeks and still always leaving enough forage behind to come back. My grandfather used to say "When it rains the ranch is huge, but when it doesn't, the ranch becomes small". This concept is why I advise people to have sufficient pasture sizes to allow successful recovery, to focus on the more productive areas first, and its best to keep them bigger for those dry spells. After all, we can always implement portable subdivisions and herding when appropriate. This will mean less investments in fencing and extra resources available to invest in other areas be it infrastructure, genetics, water, ect. A cow can survive years on poor forage but only a couple of days with poor quality water. More often than not water is the real limiting factor for herd expansion and achieving the true potential of our most important resource, land.