Before you dig near trees:

Preserving the critical root zone during construction: key thoughts and considerations.

Understanding the critical root zone (CRZ.)

The critical root zone is the area around a tree’s trunk that contains the roots essential for its health and stability. For many trees, this zone extends out to the edge of the canopy or even beyond, as roots can spread far beyond the visible branches.

Why the CRZ matters

Roots in the CRZ provide water, nutrients, and structural support. Damage to this zone-whether from digging, soil compaction, or changes in soil level-can cause the tree to decline or even die. Protecting this zone is vital for the tree’s long-term survival.

Best practices for CRZ preservation.

• Plan early and consult an arborist: Involve a tree care professional early in the project to identify the CRZ and create a protection plan.

• Install physical barriers: Set up sturdy fencing around the CRZ before construction starts, ideally extending to the tree’s dripline or as far as possible.

• Avoid disturbance: Keep all construction activities, equipment, and materials out of the CRZ to prevent root damage and soil compaction.

• Care for roots if work is unavoidable: If work near the CRZ is necessary, have an arborist supervise. Any exposed roots should be carefully pruned, kept moist, and covered promptly.

• Maintain soil health: Keep soil moisture at appropriate levels and avoid compacting the soil, especially near the surface where most fine roots are located.

• Address root damage promptly: If roots are damaged, assess the extent and follow expert recommendations to help the tree recover.

Balancing construction and tree health.

Protecting the CRZ may require changes to construction plans, but preserving mature trees adds lasting beauty, shade, and ecological benefits to your property. Taking proactive steps early on greatly improves the chances that your trees will thrive after construction is complete. Failure to take into consideration the preservation of the CRZ is one of the leading causes of long term damage and tree instability that I observe on Saltspring Island.

By prioritizing the protection of the critical root zone, you help ensure your trees remain healthy and strong, enhancing your landscape for years to come.