Crop Report – July 21, 2021

Figure 1. Manure applied 1 week ahead of cover crop seeding - growth 3 weeks after seeding.

Revitalizing Soil with Manure and Cover Crops After Wheat Harvest

Wheat in a crop rotation provides many benefits, including spreading weather risks that can impact yields and balancing workload more evenly between planting and harvest season. Wheat also provides the opportunity to revitalize the soil; to disrupt pest cycles; alleviate compaction and increase subsequent corn and soybean crop yields. Best of all, wheat in rotation provides the opportunity for livestock farms to apply manure, potentially to fields further from the storage during a part of the season when risk of compaction and nutrient losses are lower. Manure applied with most cover crops provides almost immediate visible benefit from increased biomass growth and deeper colour.

With the wheat harvest currently in progress it’s time to start thinking about which cover crops to plant and integrating the application of manure or other organic amendments.  Cover crop goals, type of manure, storage capacity and proximity of storage will influence type of cover crop species and nutrient application decisions. Cover crops such as oats or barley are easiest to manage and are responsive to the addition of organic amendments. Complex cover crop mixtures may add diversity, however with manure there are usually a few dominant species (cereals, brassicas) that outcompete most other species. Two- or three-way mixes are often more economical, especially with liquid manure.

One of the most frequent questions – should the manure be applied before or after the cover crop is planted (See Figures 1, 2 & 3)? This depends on the several things, including soil moisture levels, weather forecasts, weed pressure and equipment and labour availability. Is the seed being broadcast and the manure applied the same day, potentially in one pass?  That’s the easiest and probably safest option for maximizing the nutrients, especially from liquid manures. However, high application rate combined with high total salts content (NH4-N, K, Mg, etc.,) and sodium can result in salt injury and reduced emergence.  When manure application is planned after the cover crop emerges, it is best to wait for some growth to occur. The greatest amount of damage occurs when the cover crop has just emerged and manure application with relatively narrow spread pattern results in significant wheel track damage to the new seedlings. Manure application – injected or surface applied – in early to mid-September still provides value to growth and help prevent nutrient losses, especially if the nutrients are applied below the crop canopy.

Figure 1. Manure applied 1 week ahead of cover crop seeding - growth 3 weeks after seeding.
Figure 1. Manure applied 1 week ahead of cover crop seeding – growth 3 weeks after seeding.









Figure 2. Manure applied immediately after cover crop planting – growth 3 weeks later
Figure 2. Manure applied immediately after cover crop planting – growth 3 weeks later.









Figure 3. Manure applied 2 weeks after seeding to emerged cover crop - growth 3 weeks after seeding.
Figure 3. Manure applied 2 weeks after seeding to emerged cover crop – growth 3 weeks after seeding.









Soil micro-organisms respond to the nutrients from manure, and with the growing cover crop will enhance root systems, provide synergy for biomass production, and enrich the soil. Taking a manure sample during application will provide insight on nutrients (including secondary and micro) applied and will provide guidance for determining commercial fertilizer needs.

Ontario is Hosting the 2021 North American Manure Expo August 25-26th

Come join us for the 2021 North American Manure Expo August 25-26th coming from Ontario. Registration is free for this virtual event hosted from Maplevue Farms near Listowel, Perth Cty.

Although a virtual event, there is a lot to see. Equipment demonstrations featuring some of the latest innovations, farm tours, informative sessions highlighting current research and practical in-field tips around manure and organic amendments are scheduled during the two-day event (but available to view until the end of the year). Topics include:

  • Determining the Real Cost of Handling Manure (panel)
  • OPACA Innovations – Ontario Professional Ag Contractors share innovations that enhance application
  • On-the-Go Tracking of Applied Nutrients – Opportunities, Challenges, Economics
  • Compaction – the Problem – measuring soil compaction from manure equipment at 6, 12- & 20-inch depth
  • Compaction – Fixing the Problem – choosing tires, managing tire pressure and utilizing inflation/deflation systems
  • Managing Manure to Reduce Greenhouse Gas Emissions
  • Phosphorus and Manure – is 4R enough to reduce P impact from manure?
  • Safe Travels – Tips for staying safe from agitation to application
  • Maximizing Growing Season and In-crop Manure Application Using Draghose Systems
  • Whole Farm Nutrient ManagementTour – Visit the North American Manure Expo 2021 host farm and family to experience Ontario dairy farm innovations and a whole-farm approach to manure nutrient management.
  • Tiny Bubbles Make Me HappyTour – Aeration systems in liquid manure storages are a new-to-Ontario technology. Two dairy farms show and tell why they chose aeration and how the technology has improved manure management.
  • Solid Innovations – Thinking Outside the BoxTour beef, dairy and poultry solid manure facilities including a compost pack barn, innovative covered storage and compost production facility.
  • From Flush to FieldTour – Did you ever wonder what happens to, well you know, when you flush the toilet? Journey through a wastewater treatment plant all the way to field application of biosolids and experience the people, the processes and the products.
  • The Land Down Under – Soil Interpretive Centre Tour – An overview of the world-class Soil Health Interpretive Centre (U of G) where cutting edge soils research meets farm field manure management.

On vacation, or busy during the last week of August? No worries: Once registered there is access to all the events anytime until the end of the year. Registration is free, nutrient management CEU credits are available and the top 10 manure slogans will be revealed.  Register today at

Weather Data

LocationYearWeekly July 12 – July 18Accumulated
Highest Temp (°C)Lowest Temp (°C)Rain (mm)Rain (mm) April 1stGDD 0C April 1st GDD 5C April 1stCHU May 1st
20193110 27414609581437
Mount Forest202127135425214979951470
2019309 12913178331313
20193010 20313708791324
Thunder Bay2021338322512647821212
Fort Frances2021326015813448561333
Report compiled by OMAFRA using Environment Canada data. Data quality is verified but accuracy is not guaranteed. Report supplied for general information purposes only. An expanded report is available at

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