For me, a highlight of the production year is spending some time running the combine. I’ve done it every year since I was 15.
The 2011 harvest was a special time on my son-in-law’s farm at Annaheim. The combination of superior soil, good management and absolute cooperation from Mother Nature brought a once in a lifetime result. On a couple of days during the wheat harvest I saw the combine yield monitor showing 70 bushels per acre and better. I was happy to be called back for a second tour of duty when the canola harvest started.
Gerald Dauk and his brother Murray had discovered that slowing down (a lot) left a lot more canola in the hopper. A neighbour with engineering experience did “catch” tests to confirm that slowing down would work the grain cart harder.
So, I started out on 36 foot swaths, straight as a ruler — cut with autosteer — and with strict instructions to keep the speed to 1.5 miles per hour. The combine did not have autosteer, but if I could get the combine tires in the swather tracks, little steering was needed. At 1.5 m.p.h. with autosteer and straight swaths, keeping awake would be a problem. If a recorder was available I could have easily penned a Grainews column at the same time. It was easy to have lunch — including pouring coffee — on the run.
At one point I was given a piece of land flat as a board with quarter mile strips, so each swath was close to one acre. On the first ten swaths the monitor bounced from 68 to 72 bushels per acre at 1.3 m.p.h. It was a very uniform piece of land and crop. I had to see for myself, so every once in a while I goosed it all the way up to 3 m.p.h. and watched the monitor settle back to about 55 bushels per acre.
I finally decided to do a test for myself. This test was not pre-authorized by the boss, so I risked getting fired! The combine records the bushels in the tank, and that number has been checked against weight and found to be accurate. So I swathed one row at 1.3 m.p.h. and went on the return row at 2.5 m.p.h. (each row was one acre, according to the combine). The result was scary. At 1.3 mph, I put 73 bushels in the tank. On the way back, at the faster speed, I put in only 57 bushels.
Being a scientist, I know that two numbers can always show a difference. But is it repeatable? So I did a second repetition. Same result. Going slower, I put 15 bushels more in the tank than at the faster speed.
I thought about trying more repetitions, and switching the direction of travel in case there was a slope I couldn’t recognize. In my experience in hilly land at Dundurn, yield monitors give a very low result when going uphill and a very high result when going downhill. But if my results were real, each repetition was costing about $175 so I left it at that.
Now, I’m not an engineer and there could be fundamental problems with using monitors in this way but it is what I found, for what it’s worth.
Rather unbelievable, and I’m sure many could knock holes in the actual numbers. But there is no getting away from differences that are not acceptable. The dry, hot conditions would result in a fine mat on the sieves and many suggestions for settings could be offered, but much tinkering with settings had been done.
On September 22, 2011, Gerald obtained a weigh wagon help from the local Co-op, and two more combines came along and each did a 2.2 acre swath. At 1.2 m.p.h. Gerald’s result was 70.1 bushels per acre and other results varied from 69.3 to 60.3 bushels per acre depending on the colour of machine and speed. The neighbours’ combines went at speeds ranging from 3.9 to 5.5 m.p.h.
It was definitely worth the effort to combine the canola at such a snail’s pace this year, with nothing but good weather in view. But it is not a long term solution.
The point of this article is to raise awareness and get more people experimenting. In the June 2010 issue of Grainews, Scott Garvey explained how to measure and calculate losses and set loss monitors. His opening salvo was “it is impossible to measure grain losses through a chopper.” Any experience I have had at catching seed in a pan has left me with little confidence in the result, and dropping the chopper is not common.
The comment was made that our modern combines are really designed for corn and larger grains. The fine seeds are a challenge in separation.
When my Dad talked about the era of stationery harvest he called the machine a separator, not a threshing machine. With canola, separation is the challenge. As I watch the canola going into the combine, it’s mostly thrashed before it hits the feeder chain and I’m sure it’s all thrashed before it ever hits the rotor.
I’m sure many will have other thoughts and may think my results are crazy, but that is what I observed. I hope this stirs up interest in bigger and better experiments to get better results. †