When to Harvest
By Paul Schroden / August 2019
Paul is a Barley Agronomist based in Bismarck, ND. He has a bachelor’s degree in Agribusiness from North Dakota State University and has worked for Anheuser-Busch since March 2019.
Determining when to harvest malting barley is decided by a combination of factors including weather, barley variety, and maturity. There are two common methods to harvesting barley: Straight-cutting and swathing.
This is the preferred method to harvest malting barley because it is a one pass system. There is also less risk involved because the heads are staying up off the ground away from ground moisture which poses potential risk such as pre harvest sprouting and damage to grain quality. To determine when the crop should be straight-cut, there are a few distinct visual characteristics which signify a field is ready to be harvested.
- First, the peduncle will lose its green color which is a sign the grain has stopped filling and has begun the drying down process. Right now the moisture level is around 25-30 percent. Without drying capabilities, it is not recommended that grain be harvested at this moisture content.
- Second, the spikes (heads) will begin to gradually nod downward, as you can see in the picture below. The moisture content is gradually falling from 25 percent to 15 percent.
- Lastly, the heads will reach their final maturity when they are completely fallen over. This is when the plant has lost as much internal moisture that it can in the field, less than 13 percent.
- Growers should be advised to harvest before this stage, because once grain is at this point, it becomes extremely vulnerable to sprout and other quality issues.
Another way to try assess maturity is by walking into the field, breaking open a head, and looking at the seed.
- Full Maturity- Struggling to dent the seed with a thumbnail and it cracks when biting with teeth
- Nearly Mature - Seed dents slightly and shears when biting
- Immature- Seed dents very easily with a thumbnail and squishes when bitten into
Swathing is an alternative harvesting method to straight-cutting. It poses many risks associated with laying the grain down on the ground. However, under the right circumstances, it can be as effective as straight-cutting.
- First, correctly timing the swath is crucial because if done too early, there will still be green kernels in the sample and that may lead to rejection. The correct time to swath is when the peduncle loses its green color and the grain is done filling. Around 25-30 percent moisture.
- Secondly, swaths are recommended to be on the ground no longer than 6 days, as prolonged time on the ground may cause peeling or cracked kernels.
- Thirdly, weather plays a huge part in swathing. The swaths cannot be rained on and fields should have little to no dew present or else pre-harvest sprout will be an issue.
When deciding when to harvest make sure these three things are addressed:
- Plant maturity
- Grain moisture content
- Weather conditions in the field
If you have any questions on when to harvest, please consult your Anheuser-Busch Agronomist.
1. “On Timing Malting Barley Harvest.” | Field Crops, fieldcrops.cals.cornell.edu/small-grains/malting-barley/timing-malting-barley-harvest/.
2. “Harvest and Storage of Malting Barley.” |nmsp.cals.cornell.edu/publications/factsheet/factsheet82.pdf
3. “Harvest Strategies.” | growbarley.com/production/harvest