Story by Ann Y. Robinson
Many know Dan Andersen (’08 MS agricultural engineering, ’12 PhD) as Dr. Manure, a “brand” he created for himself. He wanted the nickname to suggest his goal of bringing a “science-based perspective with some humor in it” to the serious topic of getting the most value from livestock poop.
A professor in agricultural and biosystems engineering at Iowa State University, Andersen grew up on a Wisconsin dairy farm. He came to Ames for graduate school and ended up staying here to help farmers solve problems.
“Manure is a rich source of fertility that’s underutilized, but its management is complicated,” he says. “We have to be developing modern strategies for smarter use to encourage farmers to recycle this resource – and get good results.”
The complexities he points out include balancing variable soils and weather, uncertain nutrient levels, crop fertility needs, water quality concerns, equipment, economics and tight schedules for manure application based on regulations, retailers’ availability and weather. During presentations, Andersen talks quickly, reviewing data from plots around the state where he tests a multiverse of interactions that reflect these factors.
One focus of his current research is fine-tuning manure use with cover crops. For this, he’s exploring innovations like perennial cover crops, strip-tillage and experimenting with global positioning and row-guidance technologies that can create unique placement zones for a cash crop, a cover crop and fertilizers.
“That’s really promising,” he says. “There are also laser systems now that can quickly assess manure composition as autonomous application equipment moves through a field, and then accurately apply variable rates. We haven’t tested that yet, but they’re starting to be available. These precision management tools can improve chances for success, but they aren’t cheap, so it’s important to help farmers understand how to maximize their benefits.”
Andersen is always looking for creative ways to reach a wider group of farmers and agricultural retailers and encourage them to consider “next steps.” As a result, in 2023, he launched “Talkin’ Crap,” a podcast that offers advanced manure management advice from experts around the country to a growing set of followers. The tone can be light, but the topics are far from trivial.
“I want to help farmers succeed in making use of their manure resources, ideally benefiting their bottom line and the environment,” Dr. Manure says. “No joke.”