Monday, October 13, 2014

Your Combine Is A Weed Seed Spreader

We do a poor job of spreading residue from combines from coast to coast.  Combines are so large that they cannot mechanically spread residue past the width of the headers.  This is a problem I see on almost every farm in my travels across the country.

We basically band the nutrients that will eventually rot from the residue.  It's just like doing a poor job of spreading manure or commercial fertilizer.  We do that poorly enough already.

This article points out a real important topic today.  Combines are a weed seed spreader.  Resistant weeds are so prominent across the country that we are making the problem worse with the combine.  There is no way around it unless we control the weeds so they aren't harvested and spread.

We can set the combine so it can spread as far as possible but I haven't seen a one that does a perfect job.  There are modifications available that do a better job but few see the need of them.  Most farmers just accept combines for what they are and the job they do.  I think the poor job of spreading encourages unnecessary tillage but really tillage only hides the problem, its still there.

I hope more farmers see these problems and really attack them next spring but in this poor economy, I expect to see as many resistant weed problems as this year, if not worse.

No one wants to pay the chemical bill to kill weeds at these prices.

Ed Winkle


  1. "Combines are so large that they cannot mechanically spread residue past the width of the headers"
    Why would you want the combine to spread residue on more width than what they combine? Shouldn't everything from the combined rows go back to the same rows, so there is no loss of residue and nutrients?

    The weed seeds is a different problem, but I thought some combines were already sorting out weed seeds to keep them in a separate container for later disposal. This is probably what should be encouraged, although for the sake of me, I can't fathom how mechanical engineers can sort out all the seeds of different sizes of different weeds without seriously slowing down harvesting...

  2. You have to spread the volume past the width of the header to be spreading well enough to make it a good broadcast. It usually falls far short of the cut row. To me, good spreading always has a tiny bit of overlap.

    I have not seen seed separation commercially. That would be a giant seed cleaner larger than the combine sorting seeds from material.