Managing Lodged Cereal Crops
This article is jointly developed by Alberta Grains, Sask Wheat, SaskBarley and Manitoba Crop Alliance.
Lodging is one of the most common issues across the prairies. Growers can use tools such as plant growth hormones (PGRs) or select varieties with good lodging ratings to reduce lodging incidents, however, with the wet conditions and storms, lodging may still occur in some fields. Lodging causes delayed dry down, higher pre-harvest sprouting risks, reduced combining speed and higher disease risks such as FHB. This creates a challenging harvest situation.
TYPES OF LODGING IN CEREALS
Before discussing lodging management, let’s take a brief look at the different types of lodging.
Lodging occurs when the stems of a crop have completely or partially fallen over from their normal vertical position. There are two types of lodging that occur in cereal crops:
- Root lodging
Root lodging occurs at the crown area (plant part at or near soil surface). The stems are straight and intact, but the plant is leaning from the crown area. It is the most common form of lodging and tends to occur earlier in the season due to disturbance of the root system. - Stem lodging
Stem lodging occurs due to the bending or breaking of lower internodes. It is more likely to be induced by storms, including high wind, rain or hail events. It can also occur due to damage of wheat stem sawfly. Stem lodging usually occur later in season, when the crop is drying down.
When lodging occurs, what tools can be used to harvest the field and minimize risks?
TOOLS TO HELP PICK THE CROP UP
- Harvest direction
Assess the lodged area first. Estimate the angle of lodging and which direction the crop is lodged. Generally, harvesting in the direction against the heads (with heads facing you) is most efficient for picking up the crop. However, it can be very time consuming if one can only harvest in one direction. Alternatively, harvesting perpendicular to the direction the crop is lodged helps untangle the crop and pick up the heads.
Avoid harvesting in the same direction as lodging. This may cause the heads to be stuck under the cutter bar instead of being picked up.
- Use crop lifters
Crop lifter attachments are available for a few different header types. They aid with getting underneath the lodged plants and lifting them up for the cutter bar to cut the heads. The drop height of crop lifters can be adjusted to just above the soil to pick up the crop without digging.
- Adjust the pickup reel
Adjusting the reel as low as possible to pick up the flat plants and direct them to the cutter bar. Pickup reel should be positioned 2–4 inches ahead of knife, so tines lift crop into the cutter bar. The pickup reel should turn just faster than ground speed (1 to 1.3 times of ground speed). If wrapping occurs, slow reel or adjust tine pitch.
- Use a stripper header
Stripper headers are another useful tool to harvest lodged crop. Lodged crops have a higher risk of damp straws due to the slower dry down process. The use of stripper header helps reduce the risks of feeding large amounts of damp straw through the combine that may plug the system.
- Combine settings
Damp straw poses higher risk of plugging the combine. Adjust feeder chain tension to prevent plugging. Heads and kernels may also have higher moisture than ideal. Adjust the concave to slightly tighter to ensure green stems thresh cleanly. Choose a fan speed that allows kernel/chaff separation without blowing out lighter, drier kernels.
- Ground speed
Driving slowly is the key to harvesting lodged crops. More material will be going through the combine; therefore, the recommended combine speed is 0.5-1 mph slower than combining a standing crop. This gives the combine an opportunity to get the grain out of the straw. Monitor the combine to make sure materials are feeding through smoothly and be cautious about plugging the combine, especially in areas with green undergrowth.
TOOLS TO MINIMIZE DAMAGE OVER THE WHOLE FIELD
Lodging often occurs in sections of the field, causing the lodged area to dry down more slowly than the rest of the unlodged sections. A few tools can be used to manage the variation of moisture and minimize damage over the whole field.
- Swathing vs. straight-cutting
The choice to swath vs straight cut a wheat or barley crop often comes down to the equipment available, time management, quality management and personal preference. Below are a few considerations that relate to harvest techniques and lodged crops.Swathing is a great tool to manage uneven maturity and dry down. Swathing evens out the moisture differences and accelerates the dry down process. This reduces the period when the crop is exposed to damaging weather. However, it does come with risks. Rain events after swathing may slow down the drying process. Grain sprouting is also a concern if rain occurs while the crop is in the swath. If choosing to swath the crop, use pickup guards to minimize grain losses when picking up the swath. The reel should be rotating slightly faster than ground speed to pick up the materials efficiently.Straight cut works best in warm, dry conditions, when the crop is uniform in maturity. It is also recommended when the biomass is low and/or the crop is thin. Swathing a thin crop has higher risk of the heads directly laying on the soil surface, increasing risks of sprouting and failing to pick up the heads. - Sequence fields/patches
A wise harvest order can make a big difference. Severely lodged fields/patches should be harvested first if they are at risk of sprouting, molding or further quality loss. It is especially important if the weather is forecasted to deteriorate. If this is the case, harvest the lodged area first when the machinery can still access lodged areas without excessive grain loss or quality damage.There are a few exceptions. Harvest the standing crop first if it is overripe and shattering, and/or the lodged area is too wet or green to harvest. Logistically, if it makes more sense to clear the standing crop first to reach the lodged area, proceed with the most efficient plan. - Moisture management
Do not wait too long to harvest the lodged crops. Harvesting crops at slightly higher grain moisture can reduce PHS and disease risks typically associated with wet conditions. Early cutting also reduces shatter and head loss. The recommended moisture range for earlier harvest is:- Wheat: 14–20%
- Barley: 16–18%
The early-harvested grains need to be further dried down before safe storage. The safe temperature-moisture ranges for medium to long-term storage (5 months for barley, 6 months for wheat) are illustrated on Canadian Grain Commission.
For example, when the initial grain temperature is 15°C, the safe storage moisture for wheat and barley are around 14%. Dry, cool conditions help prevent spoilage.
- Figure 1. Safe storage chart for barley.
- Figure 2. Safe storage chart for wheat.
- Loss monitoring
Lodged crop may have higher harvest losses during cutting and threshing. Use a drop pan or check behind the combine every few passes. More information on estimating harvest loss can be found here. Also watch tailings monitor, lodged crop can overload the return, reducing threshing efficiency and increase grain loss. When needed, adjust the pickup reel, cutter bar and driving speed based on loss patterns.
MANAGE PRE-HARVEST SPROUTING AND DISEASE RISKS
Pre-Harvest Sprouting (PHS) in wheat and barley¹
Pre-harvest sprouting (PHS) is the premature germination of mature wheat and barley grains while still on the spike before harvest. In the malting industry, PHS is also referred to as chitting. PHS is triggered by rainfall spells, high humidity, and cool temperature, and relates to variety genetics. PHS leads to reduced grain quality, loss of germination energy, and can result in a significant economic hit to producers bottom line.
FACTORS UNFLUENCING PHS
Environmental
Environmental conditions at harvest strongly influence PHS; factors include rainfall, humidity and temperature. The factors are interactive and can result in loss of seed dormancy, specifics can be found below.
- Rainfall: ≥10–15 mm can trigger germination; timing and duration are critical.
- Humidity: High humidity reduces dormancy and increases disease risk.
- Temperature: Fluctuations and moderate temperatures (10–20°C) reduce dormancy; extreme heat or cold can induce dormancy or late-maturity alpha-amylase.
Phenotypic
- Morphology: Awns and waxy spikes reduce water retention (“umbrella” and “raincoat” effects).
- Seed coat: Color and permeability affect dormancy; red wheat generally has higher dormancy than white.
- Kernel hardness: Hard kernels absorb water slower, reducing PHS risk.
Genetics
- Variety genetics strongly influence the degree of PHS exhibited by a wheat or barley plant, with seed dormancy a key trait that reduces PHS risk. There are multiple types of seed dormancy, including embryo, seed coat enhanced and chemical inhibitory dormancy². Seed dormancy is a quantitative trait, meaning many genes regulate it. The extent and susceptibility to PHS differs by crop type as well, with durum wheat varieties typically being at higher risk for PHS than hard red spring wheats². Furthermore, Canadian malting barley varieties have very little seed dormancy, as quick and even seed germination is a variety characteristic valued by end users³.
MANAGEMENT
There are a few management options that can be implemented to mitigate some PHS risk, these include variety selection, planting date, seeding rate, PGR use, and harvest technique.
Variety selection
- Wheat and barley genetics have a large influence on grain sprouting. Therefore, choose a variety that has better sprouting resistance, while still maintaining other varietal attributes that are important to your farm. Consult the provincial seed guides for more information on variety PHS resistance.
Prevent lodging
- Lodge crops are at a higher risk to moisture exposure and thus have higher sprouting risk. Variety genetics and management all influence lodging risk. Balancing seeding rate, crop uniformity, nitrogen fertility and use of PGR products are necessary to reducing lodging risk.
Planting date/harvest
- Harvesting mature grain prior to moisture exposure is important to prevent PHS. Seeding early as possible and using an early maturity variety allows for the grain to be harvested prior to fall rains and overall poorer weather conditions. If swathing, leaving taller stubble can help increase aeration and encourage drying.
Storage
- Ensure grain is stored when sufficiently dry. Dry the grain to a safe moisture level if it is not sufficiently dry.
- General guidelines for safe grain storage moisture levels for select crop types.
Assessment of PHS
- The Hagberg Falling Number Test is the international standard for testing PHS in wheat. It is not a Canadian Grain Commission (CGC) grading standard. The CGC does visually inspect grain for degree of sprouting, either classifying it as sprouted kernels or severely sprouted kernels. More information on CGC grading factors can be found here. Although specific falling number values for grain selection differ annually, it is generally accepted that a 300s falling number (FN) indicates that grain is sound for most milling and bread making operations.
The Rapid Visco Analysis (RVA) test is used to determine the degree of PHS in barley grains and provide some general information on risk of germination loss in storage. This test is routinely used by malting and grain companies. RVA is not a grading factor. RVA test information can be found here.
Both RVA and FN indirectly measure alpha-amylase, an enzyme which increases when a kernel starts to sprout. The alpha-amylase enzyme breaks down long starch chains into simple sugars. Therefore, more alpha amylase increases starch breakdown and pre-harvest sprouting damage.
- Although FN and RVA are not CGC grading factors, the tests are routinely done by grain buyers and have become a common contract specification.
Takeaways
- Growers can use tools such as variety selection, plant growth regulators and fertilizer planning to reduce the risks of lodging.
- When lodging does occur, the risks for pre-harvest spouting, diseases and harvest loss are higher. Swathing, harvest sequences and harvesting early are potential ways to minimize losses.
- There are multiple tools to help pick the lodged crop up. Combine settings, travelling directions, crop lifters and stripper headers are potential tools depending on specific farm equipment.
- Pre-harvest sprouting (PHS) significantly impacts grain quality and end use. Variety selection, lodging management and proper harvest practices are ways to mitigate the losses caused by PHS.
ADDITIONAL RESOURCES
Wheat School: Flattened! Three tips for managing lodged wheat
How to Harvest Lodged Cereal Crops
Managing lodged wheat and harvest challenges after storm damage
Factsheet: Falling Number – Manitoba Crop Alliance
Combating Sprout Damage – Manitoba Crop Alliance
Pre-Harvest Sprouting in Malting Barley Explained – The Barley Bin
GRDC GrowthNotes, Barley Harvest
REFERENCES
- Hull, S. I., P. A. Swanepoel, and W. C. Botes. 2024. A critical review of the factors influencing pre-harvest sprouting of wheat. Agronomy J, 116: 3354–3367.
- Gerard, G., Hucl, P., Pozniak, C., and Briggs, C. 2021. Introgression of pre-harvest sprouting resistance from hexaploid wheat into high yielding durum wheat germplasm. Can J. Plant Sci, 102:347-355.
- Canadian Grain Commission (CGC). 2019. Using RVA to measure pre-germination in barley and predict germination energy after storage. Winnipeg (MB): CGC; [updated 2019 Feb 28; cited 2025 Sept 2]. Available from: Using RVA to measure pre-germination in barley and predict germination energy after storage