Ministry of Agriculture, Food and Rural Affairs

Table of Contents

What is RUSLE2?

RUSLE2 refers to version 2 of the Revised Universal Soil Loss Equation.

RUSLE2 is a computer program that estimates long-term average soil loss and from rill and interrill (sheet and rill) erosion caused by rainfall and related overland flow. Like its predecessor, the Universal Soil Loss Equation (USLE), RUSLE2 is used in the United States to guide conservation planning, and predict soil and sediment loads from upland areas.

RUSLE2 relies on a statistical approach to estimate soil loss from actual field and site situations. Its calculations are based on 10,000+ plot years of field observations and observations from more than 2,000 runs of rainfall simulation studies conducted on standard soil erosion plots.

With proper input and related datasets, RUSLE2 can estimate soil loss from:

What is RUSLE2 for Ontario?

RUSLE2 for Ontario is the same computer program used in the United States but includes only the datasets specifically developed to represent the Ontario environment.

You can download a copy of RUSLE2 for Ontario here.

The current version available for download is version 2.5.1.7, released June 10, 2014.

How do I Start Using RUSLE2 for Ontario?

5 training videos are available to help you become comfortable with using RUSLE2. Start with Module 1 and learn how to download the software and familiarizing yourself with the RUSLE2 input screens. We recommend you view Module 1 before downloading RUSLE2 to your computer.

Click on the links below to view the different training modules:

Once you have successfully downloaded and set up RUSLE2 for Ontario (using the information provided in Module 1), use the other modules to guide you in completing some common tasks with the software.

As you get more comfortable with the software, you can "build rotations" and "build managements", specific to your operation, which can be saved in the "My Rotations" and "My Management" folders for future use. Finally, practices such as contour cropping or the use of vegetative filter strips (support practice factor) can be selected in order to assess their impacts on soil loss due to water erosion.

Why should I switch to RUSLE2?

While the USLE is a relatively simple equation to use, RUSLE2 overcomes a number of the USLE's limitations.

The USLE is only capable of estimating a long-term average annual erosion rate. RUSLE2 can estimate long-term average seasonal, even daily, erosion rates. This is valuable as much of the sediment loading to Ontario waters occurs during the non-growing season (November through April). By breaking down soil loss estimates by season, we can better identify seasonal best management practices for protecting the soil and reducing the sedimentation of our watercourses.

There are many different management and tillage practices that farmers use on their farms. RUSLE2 has the ability to describe these different field practices in much more detail than is possible with the USLE's old C factor. RUSLE2 also has the capability of estimating the soil saving benefits of practices such as vegetated filter strips, buffers and silt fences.

Field hillslopes are generally not simple, "uniform" or "straight line" slopes. They are often convex, concave or S-shaped. See the article, Measuring Field Slopes for more detailed information on hillslope shapes and how to measure them or watch the video.

RUSLE2 can handle a variety of slop shapes encountered in the field and will estimate the erosion rate at each point along the hillslope's length as well as the sediment load leaving the bottom of it. Refer to Module 4 for instructions on how to represent complex hillslopes in RUSLE2.

RUSLE2 has other tools that help assess soil quality. For example, the Soil Conditioning Index (SCI) scores the ability of specific crop production and management practices to build or deplete soil organic matter levels. This is useful for assessing soil health, evaluating the impacts of harvesting biomass or demonstrating a farm's sustainable practices.

What if I need help with RUSLE2?

If you need help setting up RUSLE2 for Ontario or have questions, contact the Agricultural Information Contact Centre toll-free at 1-877-424-1300, or by email at ag.info.omafra@ontario.ca and they will connect you with a technical specialist.

What is Next for RUSLE2?

RUSLE2 for Ontario is a work in progress. There will always be new crops, new tillage equipment and new practices introduced to help enhance crop production and protect soil. RUSLE2 for Ontario will be updated to reflect those changes. Check back to this website periodically to ensure you are using the most current version of RUSLE2 for Ontario.

If you have a suggestion for how we can improve RUSLE2 for Ontario, send your comments by email to the Agricultural Information Contact Centre at ag.info.omafra@ontario.ca.