In The Shop: Get Ready for A Tough Harvest
Aug 25, 2010
In my "In The Shop" column in the September issue of Farm Journal Magazine I look at how improved crop genetics have challenged modern combines during harvest. Here are a few of the major points:
-Bt corn genetics have made cornstalks like small trees. Running corn head deck plates at recommended spacing may encourage corn heads to cut off the upper portions of the stalks and feed them into the combine. The extra stalks, leaves and debris can overload straw walkers or the separating portions of rotors and cause grain to "go out the back." Don't blame the combine for throwing grain out the back if the cornhead is feeding too much junk into the front of the machine.
-Bean and small grain stems have gotten tougher due to improved genetics. Sickles AND the guards they work against must be sharp. Make certain the lower edges of rock guards are "sharp" and not rounded. New sickle sections are wasted if they have to work against rounded guard edges.
-When deciding whether to replace straw chopper knives, forget the current price of knives and consider how much trouble you had last spring getting straw and residue through your field cultivator or planter row cleaners. Tougher stems and stalks wear chopper knives more quickly and result in poorer shredding action. Plus, dull chopper knives pull harder and are a drain on engine horsepower.
This harvest, take a holistic approach to adjusting combines. Don't overlook the way headers are feeding material into the combine. And accept that there are conditions--wet straw, rubbery cobs, brittle stalks, rotted tips of ears---where it may NOT be possible to get a combine set perfectly. Any mechanic that says he can set a combine to combine any crop under any condition to do a perfect job every time...well, it ain't me. I'm only human.