Island Copper Mine: Vegetation Assessment

Northern Vancouver Island · 2017 reclamation assessment

Seeded grasses and legumes competed with planted red alder across parts of Island Copper Mine. Recovery varied between reclaimed areas, making follow-up assessment important for understanding where vegetation was developing and where it needed attention.

Polster Environmental Services prepared the 2017 reclamation assessment, using field observations collected July 4–6, 2017 and previous vegetation monitoring.

The assessment examined plant establishment, competition and understory development. The historical photographs below illustrate how these processes unfolded in different parts of the mine.

Discuss reclamation assessment and field support with PES

Red alder contributes to vegetation development in several ways:

The historical planting program used red alder to establish woody cover. As the trees grew together, their canopy could reduce the light available to competing grasses and create conditions for understory plants.

The 2017 PES assessment records 505,630 red alder planted mine-wide since 1978. This is the total for the historical planting program across mine areas and years.

PES examined vegetation development along monitored transects. The assessment considered:

• The establishment and growth of planted woody vegetation.
• Competition from seeded grasses and legumes.
• The development of understory vegetation as canopy cover changed.

The original presentation follows an area at Red Island planted in 1996, with photographs from 1998, 2000 and 2009:

• Planted 1996 / Photographed 1998: Young alder growing among grasses and legumes.
• Photographed 2000: Further alder growth.
• Photographed 2009: Closed or near-closed alder canopy, thirteen years after planting.

The Red Island photographs illustrate the importance of tree establishment and canopy development. Where alder remained scattered, grasses and legumes continued to compete; where trees formed a canopy, shade changed conditions beneath them.

The 2017 assessment found differing responses across monitored areas. Restoration decisions therefore need to account for local surface conditions, competing vegetation and the intended plant community.

Planning reclamation or reviewing an established site? Talk to PES about vegetation assessment. Request a Site Assessment →

The photographs below illustrate features that help explain how a reclaimed site is developing: ground cover, tree spacing, canopy cover and the plants beneath it.

Dense grass and legume cover can obscure a lack of woody establishment. Looking at the species present helps distinguish ground cover from the development of the intended plant community.

Red Island: planted 1996, photographed 1998.

Tree spacing matters alongside tree height. Gaps between alder stems allow more light to reach the seeded understory, which can continue to compete with young trees.

Open ground dominated by seeded cover.

As alder grows, its shade changes conditions for plants beneath it. The density of the canopy and the vegetation remaining below it help indicate this change.

Alder canopy shading the ground below.

Swordfern is one of the understory species discussed in David Polster’s presentation. The presentation explains how windborne spores can collect on alder branches and wash to the ground in winter rain.

Conifers establish under the alder shelter.

• Source deck: David Polster, Seeding Grasses & Legumes, Island Copper Mine.
• Polster, D.F., B. Welchman and C. Hanks. 2001. Revegetation Strategy at the Island Copper Mine.
• Why Grass Seeding Fails

PES assesses plant establishment, competing vegetation and ground conditions to help owners and project teams plan their next restoration steps.