What is development stage?

The term development stage refers to the current stage growth and development of a forest stand. This classification provides a way of tracking the silvicultural progress of a forest stand, starting with a recently depleted (by harvest or natural processes) through a young initiated stand and finally a successfully renewed stand.

There are several pathways a depleted stand can follow that include both natural and artificial regeneration options. The assessment of whether a stand is classed as “free-to-grow” or successfully renewed is determined through a silvicultural effectiveness monitoring survey.

In the Forest Information Manual (FIM 2009), development stage is described as the current state of growth and development for a productive forest stand. The MNRF has been receiving detailed spatial silviculture data since 2002, allowing for detailed tracking of forest change. The column containing area with a depletion history includes fire, harvest, salvage, blowdown and severe insect mortality since 2002 for available Crown forest.

Area of crown managed forest by development stage

Development stage Total area Managed forest with depletion history
Depleted–Harvest 811,111 549,758
Depleted–Natural 834,438 188,056
New Natural 670,945 376,058
New Plant 741,055 419,550
New Seed 199,902 135,333
Low Quality (Management) 212,378 3,316
Free to Grow–Natural 21,405,139 502,464
Free to Grow–Planted 1,364,600 83,531
Free to Grow–Seeded 329,025 19,208
Shelterwood/Selection Stages 527,825 –
Total Area 27,096,419 2,277,273

Crown forest by development state stands with depeletion history

pie chart of Crown forest by nine categories of development stage including depleted-harvest and natural, new natural, new plant, new seed, low quality (Management), free to grow - natural, planted and seeded.

Development stage classes:

Recently depleted–harvest

Forest recently disturbed by harvest and has received no regeneration/renewal treatment. Examples are FRI image of a harvested area and a ground level view of a harvested area.

image of a harvested area, from the air (left) and from the ground (right).

Forest area depleted by harvest can remain in this class for several years, until a treatment is applied (moves to new plant or new seed) or the area is declared natural (new natural). 3% of the area within the Crown managed forest is in this development stage.

Recently depleted–natural

Forest recently disturbed by natural causes and has received no regeneration/renewal treatment. Examples are FRI image of a forest fire and a ground level view of a forest depleted by fire.

image of a naturally disturbed area (fire), from the air (left) and from the ground (right).

Forest area depleted by natural causes (fire, severe weather and insect damage) can remain in this class for several years, and can move to a harvest or salvage category (depleted harvest) or may remain as natural until it is assessed for free to grow. 3% of the area within the Crown managed forest clearcut silvicultural system is in this development stage.

New natural

Forest recently renewed by natural regeneration, but not yet assessed for renewal success. Examples are of a naturally renewed area, from the air (FRI image) and from the ground.

image of a new naturally planted area, from the air (left) and from the ground (right)

Forest area within the recently depleted development stages can follow a natural or artificial renewal pathway. Allowing growth by natural means is a commonly utilized method of forest renewal. 2% of the area within the Crown managed forest is in this development stage.

New plant/new seed

Forest recently renewed by artificial regeneration, but not yet assessed for renewal success. Examples are of a planted area, from the air (FRI image) and from the ground.

image of a newly planted and seeded area, from the air (left) and from the ground (right).

Recently depleted forest area is often planted or seeded. This treatment can include mechanical or chemical site preparation followed by tree planting or seeding. The most commonly planted trees in Ontario are Jack Pine and spruce. 4% of the area within the Crown managed forest is in these development stages.

Free-to-grow natural

Forest recently renewed by natural regeneration and assessed as successfully renewed. Example is of a naturally regenerated area assessed as free-to-grow, from the air (FRI image) and from the ground.

image of a naturally regenerated area, from the air (left) and from the ground (right).

Forest areas that were regenerated successfully by natural means. Since most area in the forest is mature with no known depletion history, 79% of the Crown managed forest is in this development stage.

Free-to-grow plant/seed

Forest recently renewed by artificial regeneration and assessed as successfully renewed.4% of the area within the Crown managed forest is in these development stages. Example image is of a planted area at free-to-grow, from the air (FRI image) and from the ground.

image of a free-to-grow planted area, from the air (left) and from the ground (right).