Managing for Resiliency & Biodiversity on the Carrizo Ranch

Michael Dennis standing near the improved riparian area of San Juan Creek.

Michael Dennis grew up on the Rancho Santa Ana in southern California, which his great- grandmother purchased in 1874. He developed a great love for the land and the ranching lifestyle there but the land was sold by his grandfather in the 1970s and was eventually developed. The development of that land was devastating to Michael and he hoped to never have to go through that type of loss again.

After Michael went to Colorado College, where he graduated with a business degree, he worked on various ranches in Wyoming and decided he needed to be his own boss. He eventually decided to be a veterinarian and ended up with a very rewarding practice in Jackson, Wyoming. Over the years, he felt the call back to the ranching lifestyle. When his stepfather died, his mother, Sally Friend, asked Michael to manage the 27,000-acre Carrizo Ranch near Santa Margarita, California. In 2006 he began the next step of his ranching journey there.

The Carrizo cattle have good weight gain on this tall grass and the longer recovery periods and higher stock density with combined herds have allowed for more establishment of Stipa and other perennial grasses.

Managing for Water Infiltration

In 2010, Sally placed all of the Carrizo Ranch in a conservation easement with the California Rangeland Trust. She and Michael wanted to conserve the ranch from development. The next step was to improve ranch management and make the landscape more resilient. Holistic Management helped them do that.

“I met Richard King in 2016 when I went to HMI’s Whole Farm/Ranch Land Management (WFRLM) Course at Paicines Ranch,” says Michael. “He was the instructor for the course. We had just gone through 3 years of drought and I had worked on the genetics of my cattle. We had just made up our mind to feed ourselves out of the drought and it was a disaster. At that point my mom sold me the cows. I was forlorn because my beautiful ranch wasn’t doing well. I had been trying to practice Holistic Management and I thought I was making progress. So, when I went to HMI’s WFRLM program I was embarrassed and practically in tears because our land was so denuded.

“After that course I really got charged up. I already had in mind that our ecosystem was developed by grazing animals and I had simplistic thoughts about bunching the cattle and moving them. The cattle responded to this management so well. I had a plan for each pasture. I might have a big group of cattle graze a pasture for 2-3 weeks and then not come back for the year, or at least an extended recovery period. Sometimes I might do something like come back early for calving. It just depended on the year.

“At that point, I had 500 head of cows, and I didn’t have as many pastures as I have now. This is a harsh Mediterranean climate. Some years with a reasonable amount of rain, then 500 cattle can’t graze enough. But 2 years of drought brings us to our knees. Now I’m trying not to feed any hay at all. Now I stockpile my pastures so I don’t feel ashamed to come back to graze them again if I need to. I keep the cattle moving all the time.

Willow saplings, sedges, and rushes are all coming into the riparian areas as well as cottonwood saplings and creeping wildrye.

“These last 3 year we’ve had a tremendous amount of rainfalls. But in the drought, we went from 700 to 200 animals. It was a huge financial loss because the market dropped when everyone started selling. Then I got 25 inches of rain and I got to see how my ranch responded and see the perennials multiplying. We got 8 inches of rain this year, which is our average, and we grew a ton of grass and had lots of leftover feed. Now I’m trying to get them to eat off that old feed with what cattle I have, plus 425 stockers. I wanted more but we couldn’t get them. I’m also keeping all my heifer calves to increase my numbers again. I’m making my culling decisions during the preg check.

“I’ve also totally changed my idea about cattle genetics. I’ve jumped in with Kit Pharo and am working to breed smaller framed animals. I sold all the other bulls and I’m just using Pharo bulls. I figure this is my last viable decade to get my dream ranch in order, to make the perfect cow, and have my pastures dominated by perennial grasses.

“Our main perennial is creeping wild rye, and I watch how the cattle are grazing it and whether I need to move the cattle to protect the plant. However, black mustard is our sentinel plant because once it comes in, I often see wild rye following. I’m seeing creeping wild rye now in places I haven’t seen it before. It used to be limited to just a couple of pastures and now they all have some. In some pastures it is more than 50% of the pasture. We’ve made some big gains after big wet years. We also have giant rye, deer grass, blue pine grass, nodding needlegrass, and bulbous bluegrass. These grasses are thriving and spreading along the water ways. I’ve found that when I crowded cattle together, then they will do more non-selective grazing, grazing more evenly, which includes grazing the nodding needlegrass. The cattle like the deer grass as well and have become less selective.

Stipa grass plants and shrubs are now moving into annual grasslands and former cropland as a critical perennial species shift on the Carrizo.

“My understanding at the time of the Holistic Management training was pretty general. My introduction to Holistic Management was through Steve Cote’s low-stress stockmanship book, Stockmanship and Handling Cattle on the Range. I just had a rudimentary understanding of Holistic Management from that.

“But Richard taught me about carrying capacity. I was nervous about this forage inventory process because it seemed so subjective and I wanted to make sure we were leaving plenty of plants for cover. It was also very time consuming and every pasture has good parts and bad parts so how do you get a good estimation with that in mind? But I came out with a workable number.

“I figure out when I need to move the cattle or have too many cattle because I want to leave a lot of stuff (litter) on the ground. I knew I was in big trouble a few years ago when the landscape was becoming bare, so I cut my animal numbers. I had neighbors saying, ‘You should have just kept your cows and just eaten in down.’ I couldn’t do it. But, I make sure I don’t need hay. If hay is $400/ton and I would have to feed 10 tons/day, that’s $4000/day! I can’t afford that.

“I have all different sizes of pastures. Some are 20 or 60 acres, and some are 200-500 acres and then some are over 2,000 acres. I’ve been improving infrastructure with 100 water troughs and I’m ready to put in more, but my driller can’t get the permit. We keep all our water troughs up and running for the wildlife even if the livestock aren’t in the pasture.

“Richard definitely helped with training my eye to estimating the amount of forage. I know which pasture I want to graze next. My criteria for moving from a paddock is that I look at soil cover. I want plenty left over. If there is only 500#/acre cover, that is not enough cover. I’ve read that you lose 7% of your residual forage every month. That amount becomes less and less. As the chance of rain increases, then the more residual I want to leave behind to grow more forage.”

This picture was taken in 2018 and shows the field in the foreground which is a heavy mixture of annuals and nodding needlegrass. You can also see the great utilization of forage by cattle that comes from non-selective grazing in this smaller pasture. Now that pasture is filled with creeping rye.

Exploring Management & Monitoring Tools

When Michael got to the ranch in 2006, he found that his mother and stepfather had been grazing the 300 cows in multiple, small groups, with set stocking. “I had some rudimentary understanding that wasn’t good,” says Michael. “I immediately started putting groups together but it was 30-60 head at a time and then I got a group up to 200 and I knew this was the way I wanted to go. Eventually, I was able to get them to 400-500 head per herd because of water being the limiting factor.  More recently, prior to the drought, I had a combined herd total of 700 head, which included one herd of 400 cows and another herd of 300 head which included heifers and 3-year-olds in one group and it worked just fine.

“The only resistance I get with this herding is from the help. They don’t want to brand 450 calves in a day, so we break the herd up into 2 groups. I’m leasing a ranch from the Nature Conservancy (TNC) and I wanted to try out virtual fencing. I am grateful for the opportunity to be part of a three-year trial. The system has been relatively easy to implement and the results good.

“My mother said this land was short grass land, but not anymore!  Some of the grasses we have are now taller than me, like the creeping rye. Again, we’ve had some shifts in one of our better pastures from six-feet tall spikeweed to wild rye once the cattle were able to go in and graze the spikeweed. I didn’t think they would do it, but I mowed some paths in there and they went in and grazed and now it is full of wild rye.” In fact, Michael’s efforts at land stewardship, and the results he is achieving, has been noted by others. He and his mother won the California Rangeland Trust’s 2020 Conservationist of the Year award in 2020.

The Madre Fire, which started July 2, 2025, near the Carrizo Ranch, burned 80,000 acres of San Luis County and several thousand acres of the ranch as it tore across 4 miles in less than 1 hour. Michael had had to move the cattle to safer ground within the ranch quickly. Luckily, the low-stress livestock handling Michael uses along with some well-trained cows allowed the herd to move quickly to safety.

While Michael doesn’t do biological monitoring himself, he is collaborating with other organizations and programs that offer that service. “I’ve signed up with Grassroots Carbon and they’ve taken 260 samples for carbon,” says Michael. “I’ve also had the folks from the Ecdysis Foundation come out and monitor. They are capturing all kinds of information and will be sending me the report. I’ve also signed up with Audubon as a ranch raising bird-friendly beef.

“Holistic Management is a doorway to not get in the way of Mother Nature. It’s helped us have deer, elk, and antelope on the ranch again. We want diversity in our grazing animals and our livestock don’t need all the grass. We’ve quit having a war on weed. We spent enormous amount of money fighting our weeds and it wasn’t to our benefit. The weeds come back or you get a worse weed. As we concentrated our cattle, the weeds got less.

“Holistic Management is a cool way of looking at the world. It makes me reflect on what I am doing on the land. For example, I don’t like the ground squirrels because they eat a lot of grass and they leave bare spots. But they don’t like thick grass, which the cattle can produce and that makes the squirrels want to go someplace else.

At the “Rancher to Rancher” meetings facilitated by Richard King and Peter Donovan, there are no experts and the focus is on learning from each other about the experiments and practices of the ranchers and what they have discovered.

“I’ve also been involved in the Rancher-to-Rancher Program (R2R). It’s set up to help us learn from each other and create community. If we all can contribute to creating a better ecosystem, then we can have better food. This work of improving the land is how I can help make the world a better place. It’s my chance to make a significant difference.”