This story originally appeared on the National Farmer’s Union blog as a series of posts. It appears here with the permission of the NFU and the author.
2800 words – 12-15 minute reading time
Some of America’s forward-thinking farmers and ranchers are innovating more flexible crop rotations that allow them to fine-tune crop choices in response to increasing weather variability. This kind of crop rotation strategy is called “dynamic cropping.” Dynamic cropping is an ecologically-based management strategy that optimizes production through the use of flexible crop sequencing. In other words, unlike fixed crop rotations whose crop sequences do not vary over the length of the rotation, dynamic cropping allows the producer to ask what to grow, as well as when and how to grow it, every time a crop is planted. The answers to these questions depend both on farm’s goals and other factors, both challenging and beneficial, such as current weather and soil conditions, short-term and seasonal weather forecasts, potential production costs, specific pest and disease challenges, the crop needs of other farm enterprises, and changing market conditions.
Dynamic cropping is more knowledge-intensive than traditional cropping methods, requiring greater familiarity with a broader range of crops than is typically necessary for most farmers. But those who have taken the plunge say that the practice increases crop yields, reduces the need for fertilizers and pesticides, increases nutrient and precipitation use efficiency, and allows them to take full advantage of changing environmental and market conditions that might inhibit the performance of less flexible management strategies. The limited research available on dynamic cropping suggests the practice offers significant benefits to agricultural producers amid the increasing uncertainties associated with climate change.
For more than forty years, Nash Huber has produced organic vegetables and fruits, food and feed grains, pork and poultry, and a variety of vegetable and cover crop seeds on 450 acres of prime farmland on Washington’s Olympic Peninsula. Much of Nash’s land is leased, and most of it is protected by conservation easements. With the help of a permanent crew of twenty-five, and an additional fifteen during peak growing season, Nash manages diverse dynamic rotations that build soil quality, provide nutrients, conserve water, and reduce pest pressures to keep the farm productive and profitable. The farm receives an annual average of seventeen inches of rain, and its production is irrigated entirely with surface waters replenished each year by snowmelt from the mountains to the south.
Nash Huber first started noticing changes in the weather in the early 1990s. The growing season seemed to lengthen as winters grew warmer, spring temperatures and precipitation grew more variable, and fall grain and seed harvests were increasingly disturbed by more frequent fall moisture. “It seems like our springs have gotten longer, cooler, and wetter,” says Nash. “We always used to get nice warm weather in late April and May. We haven’t gotten anything like that in years. Quite often, spring will start sometime between the middle of January and the middle of March, and it’s really variable. It can have too much swing and that really puts the squeeze on us.”
Nash Huber giving a tour of Delta Farm, farmland he helped to conserve in collaboration with PCC Farmland Trust. Photo credit: KIPMAN Creative
More variable summer weather coupled with increased moisture in the fall have impacted the farm’s most valuable products — grains and seeds. September weather used to be predictable, Nash explains. “You could count on thirty days of clear, sunny weather, but it is no longer that way. It used to be that our marine fog didn’t start to show itself until the middle of August. It would come in a little bit in the morning, and now we begin to see that in the middle of July. Now we begin to get showers in late August and September, and that has really impacted the harvest season since we grow so much seed and grain. It’s become difficult to get those crops dried down so that we can harvest them. Our seed crops have become very difficult because of the instability in September.”
Unpredictable weather has not changed the diverse crop mix on Nash’s farm, but it has required him to buy more tractors, tools, processing equipment, and combines to take advantage of increasingly narrow windows of time when conditions are right to get field work done. And Nash is doing a lot more dynamic cropping these days. “We switch out crops, depending on how the weather is affecting our ability to do fieldwork,” says Nash. “For example, if we can’t get into the field early enough in the fall, we put in barley instead of wheat. It’s very, very quick decision-making. We have a generalized pattern and then we switch up the crops depending upon what fields we can get into, when we can get into them and how much of each grain that we need.”
Dynamic Cropping Systems: Russ Zenner’s Story
Russ and Kathy Zenner have been farming in the Palouse Region of Idaho, near the Washington–Idaho border in Genesee, for more than forty years. Located about a hundred miles south of Spokane, Washington, Zenner Family Farms includes ground that was first farmed by Russ’s grandfather in 1935. Kathy and Russ joined the family business in 1970 and took over management of the farm fourteen years later. In 2012, Russ’s cousin Clint Zenner and his wife Alicia took on some management responsibilities, becoming the fourth generation to carry on the farming tradition of the Zenner family in Idaho.
Russ manages 2,800 acres of dryland direct-seeded crops in a three-year rotation of winter wheat, spring grains and spring broadleaf crops. In addition to those three crops, garbanzos, lentils, peas, oilseeds and grass seed are the farm’s main cash crops. Within each year of the rotation, Russ has a variety of crop types to choose from. Russ says that he considers a number of issues when choosing a specific crop for each phase of his crop rotation, but the overall goal is to increase the yield potential of the following crop. Over the years, the Zenner Farm crop rotation has shifted to emphasize spring-seeded crops to curtail both weed and disease problems in the winter wheat crop. Other important factors in crop selection include soil type, potential markets, seasonal workloads, and weather.
Changes in seasonal rainfall patterns and concerns about overall performance of his no-till production system have made Russ think about redesigning the crop rotation to increase both crop diversity and the proportion of fall-seeded broadleaf crops. “Years ago, we adjusted our rotations to reduce peak disease pressure in these no-till cropping systems,” Russ explains. “We’re planting less winter wheat than we did twenty years ago. Where it used to be 50 percent of our seeded acreage was winter wheat, we’re now down to about a third. That means two-thirds of the farm is seeded in the spring, and that’s a problem if it’s too wet.” But this plan carries some uncertainties as well, because the drier conditions in late summer and fall complicate fall planting. According to Russ, “The late summer and early fall have been drier compared to the first half of my career. That’s made it somewhat challenging to get good crop establishment on fall-seeded crops. “
As weather challenges increase, Russ appreciates the flexibility of the diverse crop rotation he has developed for the farm. “Say, for instance, a wet spring has delayed planting, we will maybe cut back on the garbanzo acres and plant more peas or lentils instead,” Russ says. “Garbanzos are the longest-maturing summer crop we have in our mix, so we can run into harvest risks in September if the crop is planted too late. Peas and lentils mature more quickly. Same way with spring grain – spring barley matures much more quickly than spring wheat. So if we need to, we can plant barley instead of wheat. And we can select from different maturity dates within the barley to fit the time available for production of the crop.”
Russ is also interested to see if there are diversity benefits to the reintegration of livestock on the farm. The newest members of the management team, Clint and Alicia, have introduced a beef cattle herd that they manage with intensive grazing of cover crops. Russ sees potential soil quality benefits of grazing cover crops, both from the additional crop diversity and the addition of manure to croplands. Although the cattle have only been on the farm one year, Russ says that the soil structure under the grazed cover crops has improved noticeably. He is looking forward to finding out how these changes in soil quality affect the yield and quality of subsequent grain crops.
Dynamic Cropping Systems: Gabe Brown’s Story
Gabe Brown has been producing cattle, feed, and food grains near Bismarck, North Dakota, for more than thirty years. When he began farming, natural resource quality on his ranch was poor. The cropland had been intensively tilled for many years, depleting the soil of organic matter and causing surface runoff and soil erosion. Weeds, insects, low soil moisture, and poor fertility seemed to be limiting crop yields, and the ranch’s extensive native grasslands were in poor health too. Soil organic matter levels were about 2% and infiltration capacity was a very low ½ in/hour.
With a focus on building soil quality, Gabe adopted management intensive grazing in 1991, and by 1993, he had converted all of his cropland to no-till. The following year, he began diversifying his crop rotation by adding peas to the spring wheat, oats, and barley that had been grown for many years on the ranch.
Today, the Brown Ranch includes about 2,000 acres of restored native rangeland that has never been tilled, 1,000 acres of perennial introduced forages, and another 2,000 acres of no-till, dryland cropland producing corn, peas (both grain and forage varieties), spring wheat, oats, barley, sunflowers, vetch, triticale, rye and alfalfa, plus a great diversity of cover crops. Throughout the year, as many as seventy different species are cultivated as crops. The grains, sunflower seeds, peas, and alfalfa are sold for cash, while cattle, poultry, and sheep are rotationally grazed through the grasslands, cover crops, and forages.
Soil organic matter levels on the ranch have more than doubled – averaging 5 percent – and infiltration capacity has increased by 16 times – averaging 8 in/hr. Brown has used neither insecticides or fungicides for over a decade, nor synthetic fertilizer since 2008, and he has cut herbicide use on the ranch by 75 percent. Corn yields at Brown’s Ranch are 20 percent higher than the county average.
Gabe says he noticed the weather becoming more extreme starting around 2006 or 2007, as flooding in some parts of North Dakota began to be the norm rather than a rare event. More variable weather has also complicated fieldwork, making crop production more difficult. “It used to be we knew we had a window of time when it’s usually dry and we can harvest some forages or plant a crop,” says Gabe. “We could plan for harvest during that dry period and plant crops according to a plan. That’s no longer the case.”
Gabe says the most effective climate risk management tool he has is the capacity of the ranch’s healthy soils to buffer more variable rainfall and temperatures. “If you can improve your soil resource and make these soils more resilient,” says Gabe, “you’ll be able to weather these extremes in moisture and temperature much more easily. I can easily go through a two-year drought and it does not affect our operation to any great extent because the soil is so much more resilient.”
Gabe appreciates the flexibility his diverse crop rotation allows him in variable weather conditions. Because he plants throughout the year, he can make adjustments to fine-tune the crop rotation plan to current weather conditions. “That’s the beauty of the diverse system of ours,” Gabe explains. “At times, we want to plant the cover crop. And then if the weather conditions change, maybe it’s dry, we’ll change the mix of that species a bit for more crop types that can handle drier conditions or vice versa. We have a really big toolbox to choose from.”
Switching out crops gives Gabe more freedom than less diverse producers to adapt his crop rotation to weather variability and extremes. This point is not lost on the conventional producers that visit the Brown Ranch to see for themselves how Gabe’s farming system works. Gabe explains, “I tell people this when I speak in the Corn Belt – those guys plant either corn or soybeans — that’s all they plant. If corn and beans don’t work out for those guys, then they’re going to have a poor year, whereas we have the ability to switch in or out of so many different crops. It just makes management so much easier.”
Dynamic Cropping Systems: Tom Trantham’s Story
Tom Trantham owns and manages Happy Cow Creamery, a 90-cow, forage-based dairy farm and creamery located east of Greenville, South Carolina. The inventor of the Twelve Aprils grazing program, Tom transitioned his ninety-cow dairy from feed-based to pasture-based production in 1983, dramatically lowering his costs while improving both herd health and milk quality.
The heart of Tom’s Twelve Aprils system is the successive, no-till planting of short-lived, seasonally adapted annual forages into a permanent Bermuda grass pasture. This keeps his soils covered and provides his cows with high-quality grazing every month of the year. The forages he uses include grazing maize, sudangrass, millet, small grains, alfalfa, and clover.
Variables such as weather, forage needs, and field-specific conditions mean that no two years are exactly alike, but on average, Tom makes five to seven no-till plantings a year. Cows graze a planting once or twice, and then the forage is either cut for hay or bushhogged to prepare for the following crop. Tom’s Holsteins consistently top a 23,000-pound herd average, and many of them are still producing well at ten to fourteen years of age.
Tom appreciates the flexibility the Twelve Aprils system gives him to adjust to changing weather patterns through the year. “I prepare for what I think the situation’s going to be,” Tom says, “and then if it doesn’t work, I just bushhog it and plant something else. That’s the great thing about my system.” Tom says this capacity to recover quickly from mistakes or other contingencies has been particularly helpful over the years.
Using no-till also provides a lot of flexibility, plus it saves time and money in fuel and equipment costs. “There’s always a challenge in farming,” he says, “but if you make a mistake. . .or maybe it isn’t a mistake, maybe it rained too much or it was too dry, with my system you’re not set back too much. Just the number of days it takes for you to get back out there and replant. But when you’ve got a hundred acres of corn silage and you lose it, you don’t have another shot until next year, so you’re done for. You’ve got to buy feed and all, and that’ll break you in a heartbeat, to have to purchase feed.”
Twenty-three years of diverse, no-till cropping and management-intensive grazing have produced very high-quality soils throughout the farm. “The organic matter in my soil is just unreal,” says Tom. “When a raindrop hits my ground, it’s just like a sponge. Hardpan is not a problem on my farm. When you walk on my fields, it’s like you’re walking on cushion.” Tom has not used any chemicals or fertilizers on his farm in twenty-nine years. “The one thing that I really believe in, as much as anything I’m doing, is no use of chemicals or fertilizers,” Tom explains. “You can see many of my fields have less weeds than a field that’s been sprayed with every kind of thing you can think of. I really like to be able to do that.”
Tom is upbeat about his farm’s ability to remain productive if weather variability and extremes increase as projected for his region. He views the combination of high soil quality, no-till planting, diverse, short-season annuals, and management intensive grazing as a very resilient production system. “I guess it depends on the degree of weather extremes that we are talking about,” says Tom, “but with my system, I am able to adjust. If one crop goes, another one’s put right in. I can respond rapidly to a situation that maybe others couldn’t.”
Guest Author: Laura Lengnick | Founder, Cultivating Resilience, LLC
The following four stories are excerpted from Resilient Agriculture: Cultivating Food Systems for a Changing Climate (New Society Publishers, 2015). Resilient Agriculture explores climate risk, resilience, and the future of food through the adaptation stories of 25 award-winning sustainable farmers and ranchers growing fruits, vegetables, nuts, grains, and livestock across America
