Agro Woodlot Program
 

Selective Harvesting in Your Woodlot

Prepared by Shawn Dias, MAFRI Woodlot Forester (BDS)

Before cutting trees in your woodlot, it's important to consider that different tree species require different forest management and harvesting techniques.  For example, aspen/poplar and pine are pioneer species that require patch cuts, greater than two acres, to get the full sunlight required for regeneration.  Alternatively, ash, oak and basswood tolerate shade and require the “selective” cutting method.

 

If your woodlot is a mixed or pure hardwood forest, you should consider the selection method for harvesting trees.  With the selection method, specific trees are pre-marked for removal, while surrounding trees are left for a later cut.  Since trees in all age classes are commonly present in mixed hardwood stands, the goal is to remove mostly the over mature, dead and diseased trees first while leaving most of the younger, more vigorous trees for a later cut.  The results of this harvesting method include enhancing the quality of both wildlife habitat and forest, while simultaneously sustaining wood lands for the future.

A woodlot management plan is important for defining long-term goals, but the immediate future requires an Operational Plan.  An Operational Plan identifies the harvest area, the volume to be removed (by species and diameter class), trail locations, reforestation methods, wildlife concerns, environmental risks and harvesting techniques. 

Selective harvesting is probably the most difficult harvesting method because great care must be taken not to damage the valuable undergrowth. Selective harvesting in any stand should be carried out during the winter months when the ground is frozen.  This helps to reduce compaction lowering the damage to roots and the forest floor and also reduces rutting thus decreasing the potential for erosion.

Since most stands in southern Manitoba have had little or no forest management, the first harvest may require a cleaning out. This cleaning out is referred to as a Timber Stand Improvement Harvest (TSI).  A TSI attacks the woodlot by taking the worst first, which initially results in mostly firewood. In general, any tree that is slow growing, crooked, crowded, damaged or diseased should be removed to enhance growth of younger trees with good form.  Nevertheless, not all poor-quality trees should be harvested since standing dead trees provide shelter and a source of food for the many bird species that inhabit mixed hardwood forests. Deciding which trees to harvest and which trees to leave requires the skill and experience of a forester.

Finally, although it seems reasonable to harvest all of the best sawlog trees, this is a mistake.  It's always important to leave a few scattered high-quality parent trees to provide seed for the next generation.

It is never too late to start a forest management plan, since forest stands that have a management plan will provide income and enjoyment for years to come, especially if the appropriate harvesting techniques are used.

MAFRI Woodlot Foresters are available to provide woodlot owners with free services that include Woodlot Management Plans, Operational Plans, Marking Trees for Harvest, Regeneration Plans, Chainsaw Safety and Low Impact Logging Training Courses.

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