Tuesday's the day when a lot of test cutting turns into full-blown wheat harvest -- weeks ahead of the normal start time -- for farmers throughout Kansas.

So far, variability is the theme of this year's harvest, says Kansas Wheat communications director Bill Spiegel. But, after a weekend of blast furnace-type weather in much of the state, this week will likely be a huge one for wheat farmers.

"Temperatures soared into triple digits in areas of southern Kansas, and hot south winds sped up the ripening of the 2012 wheat crop," he says.

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Farmers around the state report a wide window for test weight, yield and protein content. In south-central Kansas, for example, farmers hauling grain to the Andale Farmers Cooperative in Andale and Colwich are finding test weights between 57 and 64 pounds/bushel, with protein levels ranging from 9% to almost 15% and yields between 30 and 60 bushels/acre.

One bright spot is in extreme southeastern Kansas, where yields are running better than expected. Spiegel says Kansas Association of Wheat Growers (KAWG) director Jim Michael, who farmers near McCune in Crawford County, has reported high quality across the board.

"Michael says his field of the variety Everest yielded a bit better than 70 bushels per acre, with 63 pound test weights and moisture averaging 12.5. Southeast Kansas farmers planted 430,000 acres of wheat last fall; the highest total in nearly 5 years," Spiegel says.  

And though some farmers are just wrapping up test-cutting and getting into harvest full-bore, others have already been at it for a while. Farmers in southwestern Kansas have already whittled out about a third of the crop and, like other parts of the state, crop variability is a common refrain.

"Test weights there average about 60 pounds per bushel and early protein samples averaged about 14," Spiegel says. "Area custom harvesters report yields between 30 and 45 bushels per acre. The harvest is about one-third complete."

Further north, farmers and grain elevator operators expect combines to be rolling at full steam by the middle of this week, a timeframe that one grain merchandiser says is the earliest start to harvest in more than 4 decades, Spiegel says.