Hitting his moisture target on corn silage when the crop is still a bright green color was a new experience for Hilmar, California, dairyman Aaron Wickstrom.

“Normally I would look at it and say it was 2-3 weeks from harvest, but this is corn at true maturity,” Wickstrom said as he watched choppers move across the field. “We will have to re-calibrate our eyes.”

Wickstrom and his farm manager Jimmy Myers were referring to their first strip-till silage cornfield grown with surface drip irrigation, a crop noticeably greener at harvest than an adjacent flood-irrigated cornfield. Myers manages the dairy’s 1,000 acres of forage crops, mostly a double crop rotation of winter forage and corn silage

Wickstrom and his father, Tim, have operated Wickstrom Dairies and Valsigna Farms LLC in Hilmar since 2004, milking 2,400 Jersey cows and supplying milk to the local Hilmar Cheese plant. 

After evaluating conservation tillage systems and planning their transition from conventional tillage, Wickstrom and Myers no-till drilled their winter forage crop in 2014, followed by strip-tilling silage corn in 2015. The transition is complete this year as all of their acreage has transitioned to strip-till, a form of conservation tillage.

Wickstrom also invested in more efficient irrigation systems, growing silage corn on 120 acres under drip, and 500 acres under center pivots. The challenge of running liquid manure through these irrigation systems was not an issue since lagoon water is not available at the converted fields. 

Combining conservation tillage with drip and center pivots was a good choice for his farm, Wickstrom said, because not only is he accumulating valuable organic matter, but also improving water holding capacity in the highly leachable sandy soils. 

Even on the dairy's most sandy fields, Myers said, the silage crops irrigated with drip or pivots used 28 inches vs. 46 inches for flood-irrigated fields. The water savings allowed them to plant all their acres in a drought year when many neighbors are fallowing fields to save water.

Crop residue left in the fields not only adds organic matter, but shades the soil, keeping temperatures lower and allowing newly emerged corn plants to thrive. 

“The crop residue really kept the soil temperatures cooler and the plants got a good start,” Myers said. 

The conservation tillage system for Myers started with setting up borders prior to no-tilling winter forage. After harvest of winter forage in the spring, he did a pre-irrigation, burndown for weeds, strip-tilled and then planted corn. Meyers said they saved about a week’s time in field preparation.

Use of RTK satellite navigation for precision planting was essential to their success, he stressed. Wickstrom said weed pressure was noticeable in many flood-irrigated fields this year, but it was only spotty in his drip-irrigated field. 

Harvesting silage in strip-tilled field on Wickstrom Dairy

Wickstrom field being strip-tilled with new implement

He also saw a significant reduction in fertilizer use. He applies dry manure in the fall, and normally applies synthetic nitrogen (N) to fields that are not irrigated with lagoon water. This year his N applications were 50% of normal as a result of precision planting and irrigation technologies that feed the plant the amount it needs when it’s needed. 

Increased tonnage at harvest is another reason Myers plans to continue conservation tillage while adding more acres under drip. His drip-irrigated corn with strip-till averaged 34-35 tons per acre. The same variety corn using flood-irrigation with strip-till averaged 31 tons per acre. 

Wickstrom said he expects his corn silage yield under center pivot will match the drip-irrigated fields. Based on visual comparisons of the plants and ears, he said 32-34 tons per acre is likely. 

“There is really no downside to adoption of this soil-based system for silage production,” Myers said and Wickstrom agreed. “You have to adopt the mindset that while this will change how you farm, it will improve soil health and save on water and fertilizer,” Wickstrom said.

Evaluating crop residue (Jimmy Myers on left, Aaron Wickstrom on right)

Spending time in the Midwest where conservation tillage is common helped him make the decision to initiate his system here in California. “I didn’t view it as a risk, and economically, it was a no-brainer,” he said. 

Next up, Myers said he can see them pushing for higher silage yields. There are hybrids capable of producing more tons per acre, and conservation tillage will help them with this goal by improving soil health to handle higher plant populations. 

“This is a complete system and you have to do the research and plan ahead, but water savings, fertilizer savings and making better forage for your cows are good reasons for adoption,” said Wickstrom. 

Growers interested in adopting new water conservation technology can contact their local Natural Resource Conservation Service for assistance. Conservation tillage and improvement of irrigation efficiency are two conservation practices listed for funding under the Environmental Quality Incentives Program. 

Conservation tillage equipment and technical assistance is also available through a partnership between Sustainable Conservation and California Ag Solutions. Growers should consider the opportunity to initiate this system after their corn or sorghum silage crops are harvested so field borders can be set up this fall prior to planting winter forage.

Observing silage corn harvest (Aaron Wickstrom on left, Jimmy Myers on right)

An innovative equipment rental program allows growers to test the conservation tillage system before investing in their own equipment. Mikel Winemiller, customer account manager for California Ag Solutions and project field leader, provides support for growers making their first attempt with conservation tillage. Growers supply the horsepower and the operator, Winemiller said, and he helps them with equipment delivery and technical expertise. 

Sustainable Conservation, www.suscon.org, is a California-based non-profit that helps California thrive by uniting people, including farmers, to solve the toughest challenges facing the state’s land, air and water. Madera-based California Ag Solutions, www.calagsolutions.com, offers a farming system that integrates all production practices and focuses on plant and soil interactions. 

For more information about conservation tillage and the rental program, contact Ladi Asgill at (209) 604-6554 or email lasgill@suscon.org, or visit: http://www.suscon.org/blog/2015/07/ct-tour-july-2015/.