|Downie Timber and Selkirk Cedar’s silviculture program
The program covers a broad range of practices, specific to the ecological site conditions and management objectives. Our treatments include:
Site preparation treatments are sometimes completed to facilitate planting or to reduce fire hazard. In general, sufficient plantable spots exist following harvest. However, there are occasions when treatment is necessary to increase seedling survival and growth, achieve target-stocking levels, control brush species, reduce fire hazard and improve wildlife habitat.
- Low impact excavators are used to mechanical spot scarify or mound cutover areas and areas with soil compaction concerns. Most of the fine and coarse woody debris remains on site.
- In areas where non-merchandisable material has accumulated along the roadsides during harvesting, debris is piled and burned. Some accumulations may be left to weather naturally and provide important habitat for small mammals. The debris may be moved onto the roadbed as part of our program to rehabilitate secondary resource roads following harvest. The large woody debris provides both shade and a long-term nutrient supply to seedlings planted along the deactivated road surface. Extremely heavy roadside accumulations are bunched or windrowed in preparation for burning.
- Areas maybe broadcast burned in situations where fire hazard is considered to be unacceptably high and insufficient plantable spots exist.
Courtesy Peter Gribbon
Downie Timber and Selkirk Cedar is required by law to bring every cutblock harvested back to a healthy, "free-to-grow" forest state within a maximum of 15 years from commencement of harvesting. Every year Downie Timber and Selkirk Cedar plants in the region of 1 million trees. The regenerated stands are managed until free-to-grow status is achieved.
The seedlings planted are derived from appropriate supply of ecologically suitable seedlings. Where superior seed is available from the provincial tree improvement program, we will favour the use of this seed in our reforestation activities. For a proportion of our harvest areas, we encourage natural regeneration of the same species found on the site prior to harvest.
Courtesy Peter Gribbon
Brushing and Weeding
Brushing and weeding helps to control brush competition and ensure crop tree survival. Excessive competition for light, water and nutrients can have a serious impact on seedling survival and site productivity. A seedling may survive under such conditions but will not grow effectively until released from the competing vegetation. Any prescribed brush control treatment is designed to minimize the effect on native wildlife species. We use three different control treatments: herbicide, manual and biological. The immediate planting of all brush-prone sites with high quality nursery stock assists in minimizing the need for brush control.
A small proportion of blocks herbicide is applied to hold targeted vegetation in check until seedlings are tall enough to no longer be affected by the competition for light and nutrients.
Pre-commercial thinning (spacing)
This involves the removal of weak or deformed trees, providing more room for the stronger trees so they can grow faster, straighter and stronger. Unless it will create a hazard for other forest users, we leave the thinned trees on the ground to maintain soil productivity and provide habitat for small mammals, birds, insects and other creatures.
Downie Timber and Selkirk Cedar also thins certain stands to enhance timber quality, improve wildlife habitat, such as mule deer winter range, or to shorten the time required for the stand to develop old growth attributes.
A silvicultural system is a planned program of treatments throughout the life of the stand to achieve stand structural objectives based on integrated resource management goals. A silvicultural system includes harvesting, regeneration and stand-tending methods or phases. It covers all activities for the entire length of a rotation or cutting cycle.
At Downie Timber and Selkirk Cedar, many silvicultural systems are utilized including variations and combinations of clearcut, patch-cut, coppice, shelterwood and selection systems.
A series of periodic surveys are used to monitor the health and vigour of our young forests from initial establishment to second harvest. Regeneration surveys are carried out within two years of planting. These surveys assess the level of success that our reforestation efforts have achieved relative to the objectives set out in the stocking standards contained within the Site Plan.
Regeneration performance assessments are done to review the effect of different treatments on seedling survival and growth. The results of the assessment allow us to develop new and innovative techniques designed to improve the performance of our young forests. A free-growing survey is the final field check performed to certify that our basic forestry objectives have been met.
Sometimes the survey results determine that remedial action is required to increase stocking levels, control brush species, or protect seedlings from animal damage. When this occurs, the necessary action is prescribed and the area is scheduled for treatment.