Site productivity

What is site productivity?

Site productivity describes the inherent capacity of a site to support tree growth, and is most commonly measured as site index, or the height of a dominant tree at breast height age of 50 years. Site Productivity is a primary driver of stand growth, and accurate site index estimates are a critical input to the Timber Supply Review (TSR) process and other forest management decisions across British Columbia.

The Forest Analysis and Inventory Branch (FAIB) leads the collection, analysis, and provincial delivery of site productivity information. This includes maintaining the Provincial Site Productivity Layer (PSPL), conducting ground-based site index sampling, and developing the methods and tools used to estimate and monitor site productivity across the province.

The provincial site productivity layer

The Provincial Site Productivity Layer (PSPL) is the primary provincial dataset for strategic-level site productivity information. It provides species-specific site index estimates for 14 commercial tree species at a 1 ha resolution across British Columbia and is used as a key input to managed stand yield tables and TSR.

PSPL v.9.0 was developed using machine learning models trained on over 13,000 ground-based site index observations and validated against independent Young Stand Monitoring (YSM) ground sampling data. It is designed to be readily updated as new ground inventory data and improved predictor variables become available.

Learn more about the Provincial Site Productivity Layer