There are a large number of post-planting activities commonly practiced in the field of Silviculture. Some of these practices can significantly improve the quality of a newly developing forest. The management team at Replant.ca Environmental doesn't believe that our work is done once a tree is planted.
We typically implement spacing treatments (also known as juvenile thinning) on stands with young trees (typically between four and ten years in age). We use brush saws and hand saws for stems of up to 3-4 inches in diameter. We do not use mechanical harvesting equipment. We don't do a spacing treatment until a stand has had several years to start to establish itself properly, and after each desired species has become firmly established above the heights of any competing brush.
During a spacing program, we make assessments as we work through the stand, to determine which trees have the most potential for future growth. Several factors are taken into consideration here, including preferred vs acceptable species, the height and diameter of trees, proximity to other desired species, form, vigour, any evidence of potential disease, etc. Once we have determined which are the best trees to keep, depending on the previously mentioned considerations, we eliminate other competing or undesirable trees, which are cut and left on the ground to decompose. This process allows for more space and sunlight for the remaining good trees in the stand, so they will grow faster than they would have before the weaker competition was eliminated. It is an activity which is very similar to weeding a flower garden. Removing the weeds allows the flowers to flourish. Ultimately, our stand-tending efforts result in much stronger and healthier forests. Whenever we perform any thinning work on a portion of a project, we typically only cut a small percentage of trees, namely those that are unhealthy or diseased.
Normally, thinning treatments target specific post-treatment densities that involve significant reductions in stem counts. When Replant.ca Environmental does thinning treatments, we don't typically want to significantly reduce stem counts (except for grey birch, which is a weed tree that blocks growth of better species). We focus mainly on eliminating unhealthy trees that are taking resources from healthy trees.
There is another type of thinning, called commercial thinning. Replant.ca Environmental does not implement any commercial thinning programs, because we never cut or harvest trees for commercial purposes.
Brushing is an activity which typically takes place a couple years after an area is planted, or a couple years after natural regeneration starts to take hold. At this point in the growth of a stand, our young trees often fight with other plants and brush for critical resources such as water, sunlight, and nutrients. Brushing is a way to reduce or eliminate competition for the young trees, as our seedlings typically grow at a slower rate than most of the competing vegetation.
Brushing is almost always done with a special type of mechnical saw. A brush saw is designed to be used very much like a whipper-snipper (a tool used in residential grass control). A brush saw is much more effective than a chain saw for eliminating competition from small plant growth. A brush saw is also much safer than a chain saw, although it is not as effective on larger woody competition. Once stems start to get more than a few inches in diameter, a chain saw would be more practical.
Before a successful brushing application, you might look at a young stand and not really be able to see any healthy trees of desired species, due to the amount of brush and vegetation that hides them. However, after brushing, you will probably be able to see large numbers of healthy young juvenile trees, perhaps a few feet each in height.
After a successful brushing treatment eliminates vegetative competition, the growth rates of the remaining desirable trees will be significantly enhanced.
In general, pruning is a horticultural and silvicultural practice involving the selective removal of parts of a plant, such as branches, buds, or even roots. In the field of silviculture, the typical goal of pruning programs is to force trees into channeling their energy into vertical growth, so the fibre being produced by the tree goes into the height and diameter of the stem, rather than into low-lying branches. This ultimately results in healthier trees in our demonstration forests.
When we are pruning trees, we use pruning shears or saws (mechanical or hand-saws) to perform the work. Axes and machetes, and any tool that involves impact to the stem, are not effective tools. This is because they cause too much damage and scarring, and do not create a clean cut. A rough cut enhances the chance that undesirable fungi or other organisms will infect the tree. Chain saws are also undesirable, because they are too rough and lead to scarring.
Pruning should not be done during the spring, when bark is loose, as the risk of damage to the stem is greater. The late fall is a good time for pruning, for a variety of factors such as lower risk of infection by biological organisms. The winter is also an excellent time for pruning, when growth is minimal because the tree is dormant.
Pruning is also done to control blister rust in eastern white pine. Lower branches are removed, and infected bark is excised to prevent the spread of the rust.
Vegetation Management encompasses a variety of activities, such as herbiciding (either aerial sprays or targeted applications), targeted manual cutting via methods such as brushing (described above), indiscriminately clearing large amounts of vegetation through the use of heavy equipment (such as mulchers), and grazing by animals. Replant.ca Environmental does not participate in any herbicide, fungicide, or pesticide application programs! However, as already noted, we implement manual thinning programs when this activity will improve the overall quality of the forests that we manage. We also use mulchers and heavy equipment on an occasional basis when constructing trails within our demonstration forests.
Stand Tending by Replant.ca Environmental
Manual stand-tending treatments account for less than ten percent of the work that Replant.ca Environmental does as an organization. The majority of our work focuses upon planting trees, then allowing Nature to take her course. Although surgical maintenance of a plantation will usually improve the health of the plantation, our main focus is upon building new forests.