Before you park the combine after harvest, it’s important to undertake a post-harvest process that ensures your equipment is clean and ready for next season.1 This isn’t just busy work. It’s a critical step in quality assurance for your farm.
By thoroughly cleaning equipment after harvest, you will:
- Remove residual grain, weed seeds and crop debris that can harbor insects and diseases
- Reduce the risk of crop contamination and spoilage during storage
- Keep grain clean to maintain its quality at time of delivery
Here are some practical guidelines for your post-harvest equipment cleaning.
How to clean farm equipment to reduce weed seed spread
When your combine rolls through the field, it doesn’t just gather corn or soybeans. It provides a free ride for all kinds of debris that can be detrimental to crop production.
Weed seeds are among the most costly and problematic types of debris to leave unchecked. A single weed seed is all it takes to potentially set up a persistent weed population that returns year after year. Careful cleaning of your harvesting equipment can help prevent these seeds from spreading, germinating and wreaking havoc in your fields. Take special care when cleaning any equipment used in fields known to have weed populations with herbicide resistance.
Use a pressure washer or air compressor to blow out weed seeds from surfaces, underneath hoods and inside hidey holes to detach any weed seeds that might be trapped. Do the same with trapdoors and rock traps.
As a rule of thumb, you should consider investing four to five hours cleaning your combine when downtime permits.2 That might sound like a lifetime, but every weed seed removed is a future headache alleviated.
Additionally, always inspect and clean any equipment you’ve purchased or borrowed before it enters and after it leaves your farm or fields to prevent weed seed carryover from farm to farm.
How to reduce disease spread by adding cleaning to your post harvesting process
Weeds aren’t the only problem to address in your post-harvest equipment cleaning regimen. You should also plan your harvest schedule to limit the spread of disease.
First, evaluate fields for disease pressure. If you are aware of specific problems in fields, such as white mold fungus in soybeans, make an effort to harvest infected fields last. That will limit the spread of disease from troubled fields to healthy ones. That’s especially true since white mold can infect future crops via its sclerotia, which help the fungus spread.3
Second, when cleaning your combine, look to eliminate not only debris but also dust and traces of old grain that often play host to pathogens. You can use a scraping tool to remove big chunks of soil and then a pressure washer dialed to 2,000-3,000 psi to wash away finer material.4
Third, make sure you’re thoroughly cleaning surfaces of other harvesting, handling and drying equipment.5
How to clean farm equipment to reduce grain storage pests
Insects, rodents and other pests know how to take advantage of less-than-clean conditions. Don’t give them the opportunity. Before storing harvested grain in bins, clear space outside your grain bins by removing any weeds and debris within a 10-foot radius.6
Then, fill in any cracks or holes in storage facilities. Even a single larvae can cause an entire infestation in your bins, damaging or destroying the crop you’ve worked hard to grow.
When cleaning harvesting equipment, pay special attention to components pests often latch onto. These include tires, machinery undercarriages and grills, and floors. Typically, pests hang out in mud and plant material, so make every effort to blow, brush or otherwise sweep away plant matter that could give pests a lifeline.
After cleaning machinery thoroughly, it’s important to apply a disinfectant to eliminate any pest threats you can’t see with the naked eye. Make sure wastewater from the cleaning process doesn’t flow into crop fields or adjacent waterways.7
If your fields are facing weed, pest or disease pressure caused in part by contaminated equipment, experts are available to help you make a management plan. Reach out to a nearby extension office agent or a professional like your regional BASF representative.
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Endnotes
- Anderson, Meaghan, et al. Recommended Procedures for a Between‑Field Combine Clean‑Out. NDSU Extension Service, Apr. 2024. North Dakota State University, https://www.ndsu.edu/agriculture/extension/publications/recommended-procedures-between-field-combine-clean-out. Accessed 17 June 2025.
- “Equipment Maintenance.” Getting Rid of Weeds, GROW (Getting Rid of Weeds through Integrated Weed Management), https://growiwm.org/equipment-maintenance/. Accessed 18 June 2025.
- “Disease Considerations for Corn and Soybean Harvest.” No‑Till Farmer, 11 Sept. 2014, www.no‑tillfarmer.com/articles/4187-disease-considerations-for-corn-and-soybean-harvest/. Accessed 20 June 2025.
- “Equipment Sanitation: Why and How.” Canola Watch, Canola Council of Canada, www.canolacouncil.org/canola-watch/fundamentals/equipment-sanitation-why-and-how/. Accessed 18 June 2025.
- Reducing Aflatoxin in Corn During Harvest and Storage. UGA Cooperative Extension. Bulletin B 1231, 7 July 2024, University of Georgia College of Agricultural and Environmental Sciences, https://extension.uga.edu/publications/detail.html?number=B1231&title=reducing-aflatoxin-in-corn-during-harvest-and-storage. Accessed 18 June 2025.
- Clean Up Grain Bins to Reduce Insect Pests. NDSU Extension Service, 25 Aug. 2022, North Dakota State University, https://www.ndsu.edu/agriculture/ag-hub/ag-topics/crop-production/diseases-insects-and-weeds/insects/clean-grain-bins-reduce-insect. Accessed 18 June 2025.
- “Cleaning Tractors and Farm Machinery.” University of Minnesota Extension, Regents of the University of Minnesota, 2023, extension.umn.edu/farm-safety/cleaning-tractors-and-farm-machinery. Accessed 20 June 2025.
