Overview

Where mapping or technical analysis is required, a Land Evaluation and Area Review (LEAR) approach is generally recommended to identify and then designate prime agricultural areas. The Agricultural Land Evaluation System (ALES) is also used to support the designation of prime agricultural areas.

A study using these approaches may be conducted to help identify prime agricultural areas or the agricultural land base more broadly, for designation in official plans. In municipalities where the land outside settlement areas meets the definition of a prime agricultural area, a study may not be required to designate the area in an official plan.

Over time, updates to official plans, changes in land use or the availability of new information may require prime agricultural area designations to be reviewed and updated. In these cases, new or updated ALES or LEAR studies may be undertaken to support planning decisions.

Characteristics of prime agricultural areas

When evaluating whether lands should be included in a prime agricultural area, it is important to consider the Provincial Planning Statement's (PPS), 2024 definitions of prime agricultural land and prime agricultural area.

Prime agricultural land means specialty crop areas and/or Canada Land Inventory Class 1, 2 and 3 lands, as amended from time to time, in this order of priority for protection.

Prime agricultural area means areas where prime agricultural lands predominate. This includes areas of prime agricultural lands and associated Canada Land Inventory Class 4 through 7 lands, and additional areas where there is a local concentration of farms which exhibit characteristics of ongoing agriculture.

Prime agricultural areas may be identified by a planning authority based on provincial guidance or informed by mapping obtained from the Ministry of Agriculture, Food and Agribusiness (OMAFA) and the Ministry of Rural Affairs (MRA) or any successor to those ministries.

Organic soils are not mapped in Canada land inventory (CLI) and should be considered as part of an evaluation, as they can be very productive for agriculture, particularly if improvements are undertaken (for example, installation of tile drainage) or when used for crops such as certain vegetables that thrive in organic soil. The CLI agricultural capability mapping from Ontario GeoHub should be used as it provides the most current information.

Also, prime agricultural areas include areas where there is a local concentration of farms that exhibit characteristics of ongoing agriculture. When assessing this portion of the definition, consider:

  • the actual land use and whether the land is being used or could be used for agricultural purposes
  • whether investments have been made into crops (for example, perennial plant stock such as trees or grapevines) or agricultural infrastructure (for example, livestock facilities, other agricultural buildings, drainage systems, fencing)
  • the lot size(s) within the study area and the degree of lot fragmentation

In general, areas with a concentration of agricultural uses, productive soils, with a low degree of fragmentation, and investments into agricultural uses and associated infrastructure are characteristic of prime agricultural areas.

Land Evaluation and Area Review (LEAR)

LEAR is a commonly used tool in Ontario developed by OMAFA to quantitatively evaluate the relative importance of lands for agriculture based on the land's inherent characteristics and other factors affecting agricultural potential.

LEAR studies are used as a starting point to identify prime agricultural areas. LEARs may be supplemented with additional analysis and field verification prior to designating prime agricultural areas.

OMAFA surveyed LEAR practitioners from across Ontario to learn from their experiences and develop a consistent, evidence-based approach. The resulting LEAR methodology uses standardized factors, datasets and weightings to identify areas of agricultural potential using consistent criteria.

OMAFA recommends that municipalities use this approach to support the identification and protection of prime agricultural areas in accordance with the PPS 2024.

Municipalities interested in completing a LEAR should contact their local OMAFA rural planner to discuss available data and technical support.

Components of a LEAR evaluation

LEAR studies consist of land evaluations and area reviews.

Land evaluations (LE) assess inherent soil and climatic conditions for agriculture. OMAFA’s CLI mapping is used to identify and compare the agricultural capability for common field crops.

Area reviews (AR) consider other factors important to agricultural potential such as fragmentation of the land base and how land is used.

Scores from the LE and AR components are weighted and combined to provide an overall LEAR score for each evaluation unit in the study area. The highest scoring evaluation units represent areas with the greatest agricultural potential. Additional analysis and criteria are involved in delineating prime agricultural areas, including mapping areas with high LEAR scores to identifiable boundaries.

OMAFA assigns 60% of the LEAR score to LE factors and 40% to AR factors, recognizing the inherent suitability of land for agriculture.

2 AR factors are used: the fragmentation of the land base and the area in agricultural production. Combining the LE and AR factors means that areas may still receive a high LEAR score even if there are a small number of non-agricultural uses or smaller parcel sizes present, because the area is predominantly in agricultural production and the land base is relatively intact.

Once the total LEAR score for each evaluation unit in the study area is calculated, evaluation units with high, medium and low scores are grouped based on specific threshold scores determined through sensitivity analysis and consultation with OMAFA and the local agricultural community.

Principles for LEAR studies

LEAR studies should:

  • align with provincial objectives and policies
  • use the most recent and robust data available for the entire study area
  • use factors that are mutually exclusive to avoid double counting
  • limit the number of factors to avoid diffusing the importance of each factor
  • use factors that are well-reasoned and understandable to the public, agricultural stakeholders and decision-makers
  • account for differences between municipalities
  • apply a balanced approach where agriculture and natural heritage overlap

Additional detail is provided in the agricultural system mapping method (OMAFA, 2018). This document is available upon request to OMAFA's Agricultural Information Contact Centre, 1-877-424-1300.

Agricultural Land Evaluation System (ALES)

The ALES approach relies on the review and interpretation of relevant qualitative information such as soil capability and existing land use to determine if areas meet the characteristics of a prime agricultural area. In comparison, the LEAR approach is a quantitative evaluation, relying on geographic information system (GIS) modelling to assist with the identification of prime agricultural areas.

Recommended area threshold

To be consistent with the PPS 2024, OMAFA recommends that contiguous lands, generally 250 ha or larger, where prime agricultural area characteristics predominate, should be present to support a prime agricultural area designation. This threshold is not intended to prevent approval authorities from designating smaller areas with prime agricultural area characteristics.

Conversely, areas that do not exhibit prime agricultural area characteristics are recommended to be contiguously 250 ha or larger in size to be excluded from the prime agricultural area. When assessing where/when characteristics predominate, a generally >50% threshold is applied on a parcel-by-parcel basis.

Establishing designation boundaries

OMAFA also recommends applying common conventions when delineating prime agricultural areas for designation. When determining the extent of prime agricultural areas, designations should be adjusted to an identifiable boundary such as:

  • lot lines
  • roadways
  • railways
  • water bodies
  • infrastructure corridors (for example, hydro corridors) where present and mapped

Small pockets of non-agricultural uses may be present within a prime agricultural area and should not be excluded from the designation. Generally, prime agricultural areas should not divide individual parcels. However, in certain circumstances it may be appropriate to identify a designation boundary at a mid-concession point. This approach may be suitable for large lots (typically the original surveyed 40-ha lots) where the predominate characteristics drastically differ (prime versus non-prime) from one end of the lot to the other.

Resources to assist with the evaluation

ALES analysis can be supported by data and tools accessible in OMAFA's Agricultural Information Atlas (AgMaps). This public-facing GIS tool can overlay relevant data layers to compare and evaluate the characteristics of the land.

This tool can be used to assist with mapping work by providing access to:

  • CLI ratings
  • soil mapping
  • satellite imagery
  • parcel fabric
  • drainage information

Finalizing maps

Before making final mapping decisions, it is strongly recommended that ALES' study results be checked directly on the ground to confirm the designation and its boundaries. This is particularly important for areas where current satellite imagery is not available. Site visits often reveal conditions that were not anticipated based on desktop information.

This verification of facts is particularly important in areas experiencing agricultural expansion activities (such as tree-cutting or drainage improvements), which have opened or re-introduced lands for agricultural use. Consulting with local agricultural advisory committees where they exist, or agricultural organizations about the history and current use of land may also be beneficial. To achieve continuity of prime agricultural area designations across neighbouring jurisdictions, consultation with adjacent jurisdictions is recommended.