Pasture 42 - Ken and Susan Muller
Grazing orchard cover crops in the Capay Valley
Using livestock forage for cover crops throughout their hundred-acre farm in the western Sacramento Valley brings a plethora of benefits to farmers Ken and Susan Muller. According to Ken, the forage crops allow them to maximize production from their limited water, builds soil, and improves water-holding capacity. The approach works in part because it fits with their marketing strategy of fetching a premium price due to organic production methods and selling directly to customers.
The Farm
Arriving eight years ago to the Sacramento Valley from Oregon, the Mullers set up with mostly animals: 2,000 chickens, 5-8 milking cows (they no longer keep these), and an average of 5-6 beef steers, 30 pigs and 60 sheep. They’ve integrated the chickens, which all live in mobile houses, and the sheep into orchards as much as possible and move their animals every day using portable solar fencing. They have planted olives, almonds, and fruit trees, including citrus, pomegranates, figs, apricots, and a few others. They try to plant cover crops everywhere on the farm, including in the orchards, both summer and winter, though Ken says, “I guess they're more like grazing crops than cover crops because we do end up grazing everything, even if it's just with chickens.”
Cover crops that fit the season and build organic matter
Cool season perennial cover crops already grew over much of the farm when they bought it. These species required constant watering in the summer, which didn’t make sense to the Mullers who saw water as their scarcest resource. Ken says he’d rather spend money and time planting crops that grow really well in each season than trying to make crop not suited to the climate grow year-round. Now in the summer they plant species like Sudan grass which thrive in 100-degree temperatures.
According to Ken, they first grew the cover crops just to feed animals. Then they started to think more about the long-term soil benefits. Now their main goal is for the grazed cover crops – to which the animals also contribute manure – to build organic matter so water stays in the soil for longer. That way they can irrigate less. This goal has led them to no-till. They find that tilled soil needs more irrigation than non-tilled soil.
Instead of spending a lot of money applying fertilizers to balance soil nutrients, they don’t normally put anything except gypsum on the soil. By developing a thriving community of soil microorganism through diverse cover crops and proper grazing, they figure that “nutrient cycles will be sped up and crops can get what they need,”, according to Ken. They do apply some micronutrients through foliar sprays.
The Current Mix
As an overriding approach, the Mullers have assumed that more diversity is better in all seasons. In the summer, they plant sorghum, Sudan grass, cowpea, buckwheat, sunflowers, and anything else they can get to grow. They’ve even mixed in bird seed which has sunflower, sorghum, and other species. They find it cheaper than buying pre-made mixes.
For grazing, the Mullers look for species that will regrow after their animals come through. Radishes, Sudan grass, oats and other grains are pretty tough – even after an intensive grazing they still come back. Daikon grows like crazy if it gets any water on it, according to Ken. However, they keep the radish proportion low, as they want to encourage mycorrhizal fungi, which does not colonize radish well. They’ve also learned to keep the proportion of Sudan grass low to keep it from becoming the monoculture they want to avoid.
In the cool season, peas, beans and vetch are weaker. If livestock grazes them once, they don’t return, Ken says. In the summer, buckwheat is pretty fragile. It does best when seeded somewhat thickly.
Their favorite forage crop is alfalfa, a perennial. With its deep taproot, alfalfa can survive drought better than most grass species. They often overseed the alfalfa with cool-season forage species in the fall.
Timing, Planting, and Equipment
The Mullers find timing important. Ken says planting cool season cover crops in September works best if irrigation water is available. With irrigation, the cover crop can be grazed in December and maybe again in February and again in March, April, or May. However, if the seed isn’t in until November, the crop is not useful until March. In farm areas without irrigation, they plant when rain is on the horizon. In the past, rain showed up in October, but recently October rain has not been dependable.
To terminate a cover crop, they prefer to graze it, and then plant directly into the stubble. However, in the spring, they will mow or make hay when they have too much forage, planting into mower stubble. Ken notes that sorghum must be at least eighteen inches tall before grazing, otherwise it has poisonous acids (Vough 2022).
To support their no-till commitment, the Mullers have just purchased a no-till seed drill. They opted for a John Deere 750 drill, which they think is heavy duty enough to force the seed into their sometimes very hard ground. In the summer, they plant deep to protect against the high heat that can wring moisture out of any surface in very little time. The cooler weather in winter is more forgiving, so they do not have to plant as deeply. When conditions don’t allow, and before they had a seed drill, the Mullers would broadcast seed into the old cover crop and disc lightly to cover the seed.
Overall challenges
The Mullers continue to struggle with reducing compaction on their high magnesium soil. They also are looking for ways to out-compete Bermudagrass, which Ken believes they have inadvertently selected for through past management practices.
The Mullers are also looking for better strategies for protecting trees when integrating livestock. Sheep and young, aggressive chickens can decimate trees – especially young ones - by eating their bark and girdling them. This has slowed down livestock integration. They have experimented, with some success, with spraying trees with a pepper mixture to discourage sheep browsing.
Finally, using cover crops as forage in their orchards complicates harvest. By law, the orchards must not have animals in them for at least 120 days before harvesting. Finding a way to allow grazing closer to harvest would help, such as by using a wrap-around tarp or some other method to keep the harvested crop off the ground.
The Bottom Line
Ken advises that integrating livestock is a good idea if you can find an effective way to do so. Cover cropping is a part of the formula for the Mullers. It does not add much extra cost for their operation, says Ken, because they would plant the crops for forage anyway. While moving the animals around takes labor, their products sell at a premium because they are organic and pasture raised. Most importantly, they get more production out of each drop of water, harvesting both orchard products and either eggs or meat.
An important step is to pick the right animal – poultry or sheep are best because they are not as destructive as cows, goats, and pigs. However, even chicken and sheep can damage young trees, so it is best to introduce them to orchards with older trees. Ken realizes that some farms might have a difficult time marketing both animal and orchard products. But the integration works for his farm because they sell at farmer’s markets where they can distribute a wide variety of products at once and find consumers willing to pay a premium price for free-range and grass-feed products.
Reference
Vough, Les. 2022. Preventing Prussic Acid Poisoning of Livestock. Forage Information System, Oregon State University. https://forages.oregonstate.edu/fi/topics/pasturesandgrazing/grazingsystemdesign/preventingprussicacidpoisening