Harvest Timing & Harvest Now or Wait to Dry Down?

It depends on two costs that move in opposite directions. Waiting lets the crop dry in the field, cutting your drying bill, but each day standing adds field loss from shatter, lodging, birds and quality discounts. The tool plots both as curves over the days you wait; the total cost is U-shaped, and its lowest point is the economically optimal harvest day. If drying is dear and loss is slow, waiting pays; if loss is fast and the crop barely dries, harvest now.

For each day d it estimates field moisture (start moisture minus the weather-driven dry-down rate, floored at the crop's equilibrium), the points still to dry to your target, and the drying cost (points × $/point/tonne × yield). It adds the field-loss cost (loss %/day × days × yield × grain price). The optimal day is the one with the lowest total of drying plus field loss — where the falling drying curve and rising loss curve combine to a minimum.

In-field corn dry-down runs roughly 0.4–0.8 moisture points per day in warm, dry weather and falls to 0.1–0.3 points per day in cool, damp, late-season conditions. The tool uses a weather setting to scale the rate per crop, so warm-and-dry shows a fast dry-down (waiting more attractive) and cool-and-damp a slow one (waiting buys little drying).

It is the last day on which standing in the field still costs no more than harvesting today. Up to that day, dry-down savings at least offset accumulating field loss; beyond it, waiting is a net loss. So the optimal day is the cheapest day, and the break-even day is the latest you can defensibly wait — useful when weather or logistics force a delay.

Canola is the classic shatter-prone crop — pods split and drop seed quickly once ripe, so its field-loss rate is high and the window short. Wheat (head shatter, sprouting, test-weight), soybean (pod shatter, splits), sunflower and sorghum (head drop, birds) also lose fast. Corn loses more slowly to ear drop and lodging, which is why corn is more often left to dry down in the field.

Drying cost is commonly quoted per moisture point per unit of grain — removing one percentage point of moisture from the whole crop. As a rough planning figure it is about $0.02–0.05 per point per bushel, which the tool expresses as dollars per point per tonne. Multiply by the points you must remove (current minus target moisture) and your yield to get the drying bill per acre.

Strongly. Warm, dry weather speeds dry-down (more reason to wait) but also tends to reduce per-day field loss, while cool, damp weather slows dry-down and accelerates weathering and lodging. The weather setting scales both the dry-down rate and the field-loss rate, so the optimal day can swing several days between a dry spell and a wet one.

Aim for the moisture at the optimal day the tool reports — typically a little above your storage target, because the last points are slow and expensive to gain in the field and risky to wait for. Harvesting slightly wet and finishing in the dryer often beats chasing the final points, especially in shatter-prone crops or unsettled weather.

Early on, the crop is wet so drying cost is high while field loss is near zero — total cost is dominated by drying. As you wait, drying cost falls but field loss climbs; eventually the rising loss outweighs the falling drying. The sum therefore dips to a minimum and then rises, and that dip is the day with the lowest combined cost.

No — they are representative planning values from extension harvest-timing, dry-down and field-loss studies, not a measurement of your field. Dry-down depends on hybrid, weather and canopy; field loss depends on variety, lodging and pest pressure. Use the tool to frame the decision and the dollars, then adjust the rates to your own experience and let the forecast and grain quality override a close call.

Use the break-even wait window: any day up to it costs no more than harvesting today, so you have flexibility for weather and machinery. Past the break-even day, factor the rising loss into your scheduling — and remember that a real rain or wind event can wipe out the modelled savings, so when the call is close, take the grain off.