An ambitious, University based, USDA sponsored research project investigating
the sustainable production and distribution of bioenergy and
bioproducts for the central U.S.

Harvesting Bales from Start to Finish

By Ali Lenger

Bales being harvested with the help of a baler machine. Photo Credit:CenUSA Bioenergy 
Every step adds precious dollars and cents when harvest time rolls around. To maximize profits, a bale’s journey from the field to processing facility must be efficient and economical.

But what is the best way to maximize harvest efficiency for of perennial grasses? According to researchers studying the logistics of harvest at CenUSA Bioenergy, it is by thinking carefully about all the harvesting steps and maximizing their efficiency: cutting, drying, harvesting and transportation of bales.

“It's no use having a lot of capacity for baling, if you don’t have the capacity to move that material quickly,” said Stuart Birrell associate professor in Agriculture & Biosystems Engineering at Iowa State University and a CenUSA Project co-director. “Before you invest in a much larger piece of machinery for one of the operations, make sure that it’s not one of the other operations that is your restricting factor.”

The first three steps of harvesting are typically done using a “haybine” or mower conditioner. The machine mows, conditions (crimps or crushes hay, so it dries more easily), and creates windrows. A wider windrow allows for faster drying time, but can be harder to pick up and bale.

Maximizing efficiency also means deciding, what is the best size and shape for bales?

According to Kevin Shinners, professor of Agricultural Engineering at the University of Wisconsin, Madison and co-Project Director with Birrell, large round balers (typically 5 x 6’) are both common and cheap. As they are round, they shed water, helping maintain quality when stored outside. But compared to square bales, round bales are less dense, harder to stack and less efficient to transport.

To improve efficiency, some farmers are baling their crop into larger round bales (8’ x 8’) or large square bales (typically 3’ x 3’ x 8’ or 4’ x 4’ x 8’). Larger bales lower transportation costs, but add capital costs. Small square bales are popular and easier to move, but have higher labor costs, taking more people to move and load the bales onto a truck.

”A very big issue with the transportation, to a certain extent, is the miles you have to travel, but a lot of it is how quickly you can load and unload the system,” said Birrell.

In terms of storage, there are many factors to look out for. Moisture management can become a large issue because the material can lose material to bacteria said Birrell.

“I might have lowest harvesting cost for one scheme, but the transporting and processing cost may be so great that a higher harvesting cost system may end up costing having a lower total cost at the end of the day,” said Shinners.

“Every day that you get out of that optimum period you’re losing yield, but the longer you can harvest the most acres,” said Birrell. “(Y)our capital costs are lower per acre.”

You can learn more about harvest CenUSA’s research here.