Protecting water, fine-tuning cropping systems

Gloria Hafemeister
Discovery Farms Wisconsin

WISCONSIN DELLS – “Nutrient crediting from manure is like on-line shopping,” according to Amber Radatz, co-director of the UW-Extension’s Discovery Farms program.

Speaking at the Discovery Farm’s annual conference in Wisconsin Dells last week, Radatz illustrated, “When you order it online you wait for it to arrive.  If it doesn’t arrive you don’t put out another order. You check to see where it is.”

According to Radatz manure is the most complex issue to deal with on a dairy farm.  When there are close neighbors, there needs to be a concern for odors. When there is not enough storage, decisions need to be made about when and where to spread it, particularly in winter when a growing crop will not immediately take up the nutrients.

To manage it producers need to know the value of the manure, when that value is delivered, how much is enough for a crop and how much is too much.

Amber Radatz, co-director of Wisconsin Discovery Farms program, has a technical background in manure management and nutrient loss.

“We are here to provide science and tools to deal with manure, balancing and protecting the environment while being agronomically successful,” she says.

Discovery Farms provides access to the tools and farmers must figure out which one is best for their farm and how they will put it to use.

UW-Discovery Farms has monitored water quality on farms that utilize manure for over a decade. 

Radatz says, “There is tremendous power in understanding the conditions that lead to runoff and a heightened risk for nutrient loss.  Using that knowledge to make small tweaks can pay big dividends towards achieving sustainable levels of nutrient loss.”

Things like depth of snow, how it melts, how frozen the soil is, and rain all determine the amount of runoff during winter, especially in the month of March, she points out.

To avoid problems she suggests avoiding manure application shortly before snowmelt and runoff.  Also, consider placement.  Using no till or limited tillage does a great job of minimizing soil loss.

Continuous surface application of manure without incorporation creates high levels of phosphorus in the upper soil layer that can lead to increased dissolved phosphorus. 

Radatz admits it can be a challenge to get good placement of nutrients without doing too much disturbance and causing soil loss. 

“Placement of phosphorus is a subtle adjustment that needs more attention, but not at the expense of soil conservation,” she notes.

She concludes, “If you must spread manure every month of the year, work with local soil conservationists to identify fields that are at lower risk for surface runoff or groundwater impact.”

She stresses the importance of developing a system and goals.

“Start with a system that works for your farm. There is variation in nutrient availability but this isn’t a reason to lack confidence in crediting. It’s a reason to verify the specifics for your own farm. Start by verifying and using nutrient credits from all sources and then test and develop realistic goals.”

Precision and decisions

Precision agriculture has helped tremendously with a farm’s ability to monitor nutrients and change the way nutrients are delivered to crops. Farmers are monitoring yields and moisture and placing more nutrients where needed and fewer nutrients where they will likely be wasted.

Professor Raj Khosla of Colorado State University, addressed that topic and shared ideas for understanding data that is collected from fields and using that information to make meaningful decisions.

He says, “With the advent of Precision Agriculture over two decades back, agriculture slowly started to embrace the advances of information and communication technologies.”

Noting that farmers are beginning to realize the advantage of using these technologies on the farm he says actually using the data to make changes that will improve production and protect the environment is a little slow to come.

He says Precision Agriculture is actually less complex than most people think.

“It consists of five ‘R’s application including the right input, at the right time, at the right place, in the right amount and in the right manner,” he says.

He points out that it is not necessary to use large and complex machinery but, rather, success of precision agriculture lies on how creatively farmers are able to institute the five “R”s in a manner that is site-specific, locally adaptive, operationally feasible and above all affordable.

There are many challenges in storing, sharing and analyzing data from fields that can then help the farmer develop a prescription for farming that field. There is technology to assist in soil sampling, remote-sensing, soil moisture sensing, crop health sensing, prescriptive input applications, spatial variability, yield mapping and more. 

Many farmers today are using some or all of these tools to guide them in their planting, fertilizing and pest management decisions. Several farmers and crop consultants who have used these tools shared what they have learned as a final part of the Discovery Farms conference.

Learning new things

Among the couple hundred attendees at the conference were several of the leaders of Dodge County’s new Healthy Soils – Healthy Waters group.

Marty Weiss, Beaver Dam says he enjoys the Discovery Farms conferences because they look at real farms and take into consideration the many different types of soils and weather conditions.

“I always learn something new when I come to these things,” he says.

He enjoys learning how others are using available technology to improve the overall health of the soil. His past experience grazing helped him understand the benefits of getting diversity into the soil. Now that he isn’t raising livestock he has gone to establishing cover crops to accomplish that goal.

“I do it for diversity in the soil and to get the biology going,” he says.  “Each thing that I plant has a purpose.”

Tony Pierick of Watertown also enjoys trying new things on the farm as a means of improving soil health. He attends the Discovery Farms conference each year to get practical information from other farmers and from the researchers who monitor results of various ways of doing things on a variety of real farms under real-life conditions

He has been no-tilling on his Watertown farm since the 1990’s and in the last few years has incorporated cover crops into his plan. Eighty-percent of his 1000-acre farm now has cover crops.

Pierick would like to see more farmers attend the Discovery Farms conferences and farm tours to learn about all the new ways to fine-tune their cropping system. Using today’s tools not only improves water quality and production but it can also save farmers money by not using more fertilizer than is needed.

So what’s ahead for Discovery Farms?

Raddatz suggested, “We’ve looked at typical systems in Wisconsin. Now maybe we need to look at some of the less common systems that farmers are developing on their own to create healthy soil, grow better crops and protect water quality.”