Some weeds aren't resistant – just hard to control. Then again, other weeds are hard to control because they're resistant. It's a catch-22 that three Midwestern farmers try to steer clear of. It's also one you may need to consider as well.

"Maybe you didn't get control three years ago on waterhemp, but you blamed it on dry weather," says Rick DeGroote, Parkersburg, Iowa. "The next year maybe you sprayed late. You keep coming up with excuses, and before you know it, you've got a population of resistant waterhemp that's tough to handle."

Looking for options: These farmers visited the Dow AgroSciences demonstration farm and shared concerns about weed control. Left to right are Kenny Wells, Brett Reiss and Rick DeGrote

Waterhemp was a bigger problem in Iowa, then Illinois, before it finally reached Indiana. Going into 2013 Bill Johnson, Purdue University weed control specialist, documented it in about one-third of all Indiana counties, and suspected it was likely in more counties. He does not know how many of those counties have waterhemp resistant to glyphosate.

Waterhemp is a cousin to redroot pigweed, an annual in Indiana that has been here for years. It is also related to Palmer amaranth, the monster from the South that's now confirmed in 18 Indiana counties this year.

Kenny Wells, St. Joseph, Mo., says "Our program was glyphosate, glyphosate, glyphosate year after year. Now we have resistant waterhemp. We must look for other options."

Many others have relied on glyphosate-heavy programs as well. Most weed control specialists say the days of cheap weed control thanks to glyphosate alone are over.

Some farmers may consider tillage, but it's a last resort for Brett Reiss, Plains, Kan. "We only get 15 inches of rain per year," he says. "Every time I till I lose valuable moisture. I'm looking for herbicide options that will work instead so I don't have to till," he says.