A lot of grain has been harvested at low moisture contents this year. Farmers are paid at a base price of 20% moisture content. Drier grain means weight loss.

So, a trailer weighing 10t at 20% moisture content will weigh more than the same grain at 15% moisture content.

In this article, we will show you how to correct your grain yield to 20% moisture content, or another grain moisture content, and also examine the amount of weight loss or gain from low and high moisture contents. It will also help you to calculate weight loss when drying grain.

Growers can then work out if the moisture bonus they are being paid is making up for the weight loss or figure out what the optimum weight for individual farmer to harvest at is.

What you need:

  • Grain yield or weight.
  • Moisture content when harvested.
  • Base moisture content or dried moisture content.

    • Calculation

    The new weight is equal to the initial weight multiplied by the sum of dividing two dry matter weights. So, you minus the initial moisture content from 100 and divide it by 100, minus the new moisture content.

    New weight = initial weight x (100 – initial moisture %)/(100 – new moisture %)

    This sum below shows that the yield of grain harvested at 15% moisture content when corrected to 20% moisture content. The 3.5t/ac of grain harvested at 15% moisture content is equivalent of 3.72t/ac at 20% moisture content.

    3.5 x (100 – 15)/(100 – 20) = 3.72t/ac

    How does this impact income?

    So how does this affect income? To be clear, the examples below are not based on any merchant or co-op, and all will differ from year to year depending on circumstances and energy prices. Some merchants or co-ops will pay a base price from 20%, some pay below this or start slight above this.

    The bonus or deduction will vary from place to place. It could be €3/t, it could be €2.50/t, it might be €2/t, and it might be paid down to 16% or 15%. It will vary across the country. The examples below are only guides and designed to allow you to work out your own yields and incomes.

    Cut at 15%

    Lets take an acre of barley. If this acre yielded 3.5t/ac at a moisture content of 15%, a base price of €200/t (for example purposes only) and a moisture bonus of €3/t paid down to 16%, it would return €742/ac. At a base price of €200/t and a moisture bonus of €2.50/t down to 16%, the income would be €735/ac. At a base price of €200/t and a bonus €2/t down to 15%, the income would also be €735/t.

    Cut at 20%

    However, had that same acre of the crop been cut at 20% moisture content, it is estimated that it would have yielded 3.72t/ac. At a base price of €200/t and without any moisture bonuses, the crop would bring in €744/ac.

    Cut at 21%

    If that grain had been harvested at 21% moisture content, its yield is estimated at 3.77t/ac. At a base price of €200/t and subject to a moisture deduction of €3/t for the 1% moisture content above 20%, the grain would bring in €742.69/ac. At a base price of €200/t and a moisture deduction of €2.50/t per point, the income would be €744.58/ac. At a base price of €200/t and a deduction of €2/t per point, the income would be €746.46/t.

    Cut at 14%

    Going a step further, if the same crop was cut at 14% moisture content, it is estimated it would have yielded 3.46t/ac. At a base price of €200/t and a moisture bonus of €3/t down to 16%, this would return €733.52/ac. At a base price of €200/t and a moisture bonus of €2.50/t down to 16%, the income would be €726.60/ac. At a base price of €200/t and a bonus €2/t down to 15%, the income would also be €726.60/t.

    Cut at 12%

    If it was cut at 12% moisture content, the yield is estimated at 3.38t/ac. At a base price of €200/t and a moisture bonus of €3/t, that equates to an income from the grain of €716.70/ac. At a base price of €200/t and a moisture bonus of €2.50/t down to 16%, the income would be €709.80/ac. At a base price of €200/t and a bonus €2/t down to 15%, the income would also be €709.80/t.

    Things to consider

    No other factors have been taken into account, such as bushel, or protein, or premium markets. The prices used are for example purposes only and do not give any indication of where harvest prices will land.

    All growers should check with their co-op or merchant on base prices, moisture content base levels, moisture bonus payments and moisture deductions, as well as the moisture percentage they pay down to and the moisture levels they will accept.

    Can’t control all the factors

    Often when you are cutting you will have no control over the moisture contents, particularly where they are too low, but often you do have control.

    Spring barley this year is being harvested at low moisture contents, but would not thresh any sooner for growers. Winter barley and winter oats' moistures dropped rapidly in the heatwave and farmers with large amounts of crops to cut could not cut any faster, so crops were cut at low moisture contents.

    In wet years, it is hard to control the moisture content. Patience is needed to cut crops at suitable levels. For example, malting barley is not meant to be harvested at higher than 21.5% moisture content.

    At a moisture content of 20% you’re receiving the base price. You are not suffering weight loss. You are not losing out on moisture bonuses once you hit the cut off and are not taking deductions.

    As we know though, harvest and weather will decide, for the most part, what levels you harvest at will be determined by when you can cut, but if you can avoid very high or very low moisture contents, you should be better off.