If you're interested in the latest trend in drying haylage faster — wide swathing without conditioning — consider University of Wisconsin research before jumping in.

The wide-swath concept is simple: as swath width increases, more hay is exposed to the sun for faster drydown. But the reality is that most commercial windrowers and mower-conditioners can't, at this time, lay swaths their full cutting width because the conditioning rolls aren't that wide.

So some growers are taking off their conditioning units. That prompted Kevin Shinners, UW-Madison ag engineer, to examine whether wide, unconditioned swaths dry faster than narrower conditioned swaths.

“In order to get a benefit from not conditioning the material, you have to be able to lay it out twice as wide as your conditioned crop,” he says.

A 14' mower-conditioner with 5'-wide conditioning rolls taken off could potentially make an unconditioned swath that's more than two times as wide as a conditioned swath.

“If you could lay it out 14' wide without conditioning, it would dry faster than that 5' conditioned swath would,” says Shinners.

But say the 14' machine was able to lay out a 7½'-wide conditioned swath, Shinners adds. “In that case, it would not be beneficial to take the conditioner out and lay the swath 14' wide. You'd get just as fast drying — or faster — by conditioning and laying it at 7½' wide. Also, most wide mower-conditioners cannot lay material full width without major modifications, even if the conditioner is removed.”

Another concern with wide swaths: driving over the crop. With full-width swaths, at least one tractor tire on pull-type mower-conditioners will run over the previously cut swath, slowing drying and adding soil contamination, Shinners says.

“Maybe driving over the cut crop is a little less of a problem in haylage than in dry hay,” he adds. “But you have to worry about how you're going to pick that stuff up. If you push it into the ground, then start raking, or are picking up rocks or dirt into the windrow when raking or merging, that's not a good thing.”

“It's tough to envision with any pull-type machine, or most of the windrowers out there, how you can actually lay this crop out full width of the cutting platform. The one situation where I have seen this work is on a large sickle platform like MacDon has. It has fairly narrow conditioning rolls and a 25'-wide cutting platform. The producer took the back out of the machine and just drops the material directly on the ground. In that case, you could really produce an extremely wide swath,” he says.

Nathan Strahm, a custom harvester from Monticello, WI, did just that. His MacDon windrower has no conditioning rolls and he also took off its commercial draper belts. He at first added a few homemade rollers, with draper belt motors coupled to them, to keep hay from hanging up on the head's support arms. That worked the first year he tried the unit, but last year the crop caught up in the support arm area. He's planning to replace the rollers with small draper belts, about 1' in width.

After converting the windrower, he also invested in a 30' merger to combine those swaths hours after mowing.

Strahm was careful to keep his MacDon draper belts intact in case the wide swathing didn't work. The windrower's resale value should be good, too, since the belts haven't been used, he says.

Shinners stresses that growers shouldn't abandon conditioners unless they can lay crop more than twice the width of a conditioned swath, as Strahm did. But producers should always consider laying conditioned swaths as wide as possible to hasten drying. Conditioners also help shape windrows, he says, something growers will want in lower-yielding later cuttings.

For more on Strahm's wide-swath conversion, see Hay & Forage Grower's May 2006 article, “Wide Works Wonders,” also found online at hayandforage.com (put headline in search box and click go).