Dennis Buckmaster used a hair dryer, plastic piping and a bit of ingenuity to build a handy tool for checking forage moisture levels at harvest or feeding time.

Buckmaster, a Penn State University ag engineer, says his simple forage sample dryer is faster and easier to use than other methods.

“It's inexpensive, provides a high volume of air and is inexpensive to replace,” says Buckmaster after comparing his dryer to Koster testers and microwaves. “If the blow dryer goes, for $10 and a trip to your favorite department store, you can replace it.”

The blower end of the dryer is connected to a CPVC pipe attached to a funnel- or vortex-shaped container made from two round duct reducers. A 200-gram hay or silage sample is put into the dryer. Then a cover made from wood and window screen is secured on top and the dryer is turned on. It takes 20-60 minutes to dry a sample. While the sample is blown about within the dryer, a grower can finish some chores and not worry about burned test results, Buckmaster says.

“With the vortex, you don't have to stand there and watch it like you would a microwave,” he says. Although a microwave may produce results faster, the vortex dryer is faster and less expensive than a Koster tester. “The vortex is 35% quicker than a Koster,” he says.

In comparing his dryer with a Koster tester, Buckmaster used a drying oven as the control gauge for accuracy. The vortex is less expensive and even more accurate than a Koster tester, yielding moisture estimates within 1% at least 95% of the time, he points out.

Buckmaster's dryer also provides very uniform drying because the sample has air moving through and around it.

One benefit to switching to this low-cost, low-maintenance dryer is that growers can easily compile more data.

“People who sample in microwaves often don't take the time to do replicate or triplicate samples because they have to stand there.” If someone is getting ready to fill silo, he runs the harvester to get one little sample. He dries it in a microwave and gets a number, often basing the whole silo on that one number, he says. “The 200-gram sample you can do in a vortex dryer is also larger than the samples most people dry in a microwave oven.”

“I would encourage producers to spend $90 to $200 (to build or buy three vortex dryers) and, in the same amount of time, get three numbers and take an average. If there is only one sample, there is no clue whether it is a good or bad sample,” he says.

Anyone interested in ordering pre-built vortex forage sample dryers — or building their own — can get ordering, building, and operating instructions at: vortex.

What To Buy To Build A Moisture Tester

Here's what you need if you build a moisture tester:

Blow dryer, 1,200- to 1,600-watt.

CPVC or PVC base, 4" in diameter × 7" long, schedule 40.

CPVC tube, 1.5" in diameter × 6" long, schedule 40.

CPVC coupling, 1.5" in diameter.

Round duct reducers, 1 each of 6" to 4" and 9" to 6"galvanized steel.

Furnace filter.

Window screen, two pieces, 10" in diameter.

Wood for lid, 1 each of ½" plywood, 9" in diameter and 11" in diameter.

Wood or sheet PVC for floor, ½" thick, 4" in diameter.

Fastening hardware, pop rivets, screws and CPVC glue.

Note: The blow dryer's outside diameter should be compatible with CPVC coupling used as a connector.