Rapid ecological restoration of aggregate sites: replication of mature hardwood forests

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The Ontario Aggregate Industry generated $44.7 billion of gross production, $13 billion of labour income, $22 billion of GDP (3.5% of total GDP), and 245,000 full time jobs in terms of direct production, immediate secondary impacts and downstream impacts. Aggregates are vital to infrastructure construction on Ontario and are a finite resource. Close-to-market extraction often requires removal of mature hardwood forests which can never be restored onsite due to permanent flooding of most pits and quarries. Aggregate producers plan off-site creation of new hardwood forests resembling those removed, but conventional practices are too slow and only partially replicate the ecosystem services of mature natural forests. The issue is stark: It can take 150 years to restore 80% of a forests but aggregate producers must conform to licences requiring evidence that full ecosystem compensation goals will likely be met - and they must do this within the 30-40 year lifetime of typical aggregate extraction operations.With the support of The Ontario Aggregate Resources Corporation, Walker Industrial Holdings Ltd (and subsidiary Walker Aggregates Inc.), it is propose to develop new strategies for restoring mixedwoods forests - rapidly, completely and cost-effectively. Progressive forest planting and natural regeneration strategies will be experimentally combined with nucleation (cluster planting of key tree species) and translocation of topsoil seed banks from natural stands being removed for licenced aggregate operations. This will mean saving the soil and biota from sites to be quarried and reusing them on sites that have been decommissioned. Treatment combinations supporting rapid emergence of diverse and characteristic target forest communities will significantly advance forest compensation practices, thereby satisfying regulators, facilitating access to close-to-market resources and improving the sustainability of the aggregates industry. Strategically, accelerated ecological restoration of forests could be applied across Canada to expand and reconnect existing forest fragments.