Under ideal conditions, minimal tools are required to condition grain properly for long-term storage.

But as Western Canadian farmers can attest, perfect harvests are few and far between.

All too often, a late rain or early snow will delay harvest operations, leaving you with tough or damp grain.

Thankfully, tools and strategies for grain storage have been fine-tuned. With the right equipment and plan, you can extend your grain-drying season and effectively remove moisture, even when the temperature dips all the way down to minus 10 C.

Natural air drying

Natural air drying is the preferred — and most cost-effective — method of drying grain. The strength of your fans, however, determines your success, as do environmental conditions.

A higher airflow rate of one to two cubic feet per minute per bushel (cfm/bu) is required to dry most grains. At lower rates, the grain temperature can be lowered — provided the air outside the bin is cooler than the grain — but you won’t see drying.

Even with the additional power, natural air drying can be a slow process. According to the Prairie Agricultural Machinery Institute (PAMI), it can take as much as two weeks to dry wheat from 16.5 per cent to 14.5 per cent at one cfm/bu, depending on air temperature and relative humidity outside.

Equilibrium moisture content charts that show the effect these conditions can have on your ability to dry grain are available for most crop types (see chart below). Using the outside temperature and relative humidity, you can see the moisture content that will ultimately be reached using natural air drying, provided the environmental conditions remain stable.

Under certain conditions, you can actually add moisture to the bin, so it’s always important to closely monitor the environment.

Supplemental heat

To dry grain effectively using natural air drying, the average outside temperature should fall between 10 and 15 C. Once it dips below that, you’re unlikely to see any results from natural air drying, which becomes an issue when harvest stretches into the late fall.

In these cases, supplemental heat can help extend your drying season while also shortening the time it takes to dry grain.

With a heater attached to your fan, you can significantly raise the ambient air temperature. PAMI has found that, generally speaking, for every 10-degree increase in temperature, the relative humidity of the air entering the bin is cut in half.

Today, gas and electric heaters are available that can provide 60,000 to 200,000 BTU. The type and size of heater you select will be based on your ability to supply the energy needed to power the equipment.

If a more advanced drying system is needed, a batch or continuous-flow stand-alone grain dryer can be used. These systems are more expensive and costly to operate, but have increased capacity and will extend your drying season even further.

When is grain dry?

For safe long-term storage over five months, canola should be conditioned to eight-per-cent moisture and a temperature under 15 C. Canola and other crops, however, can be sold at moisture content levels above that.

Questions about grain conditioning? Speak with your local Pembina Co-op Equip Team Member.