CFS: Red Alder Natural Growth
History
During the 1980's, this area was cleared for a commercial conifer seedling nursery run by Dr. Oscar Sziklai until 1995. Styroblock containers were used for white spruce and lodgepole pine seedlings. After the nursery was closed, red alder seeded in naturally and became the primary overstory species in this area. The white spruce, lodgepole pine and other conifer species that form a secondary canopy layer in this area were planted at various times for short term student experiments.
General
Elevation: 90 m above sea level
Aspect: Southwest-east
Crown Closure: 89 %
Major Tree Species by Volume: Red Alder (Dr)
Minor Tree Species by Volume: Spruce (Sx)
Average Height of trees: 17.84 m
Tree Layers
The pioneer species, red alder, is usually the first to seed in after a disturbance and is later replaced by longer lived, shade-tolerant trees. In this case, the red alder continues to be the major species in the area with average heights of 29 m. Alder is a really important species in forest succession because it enriches the soil with nitrogen via symbiosis with Frankia bacteria in root nodules. The planted spruce are not native to this area.
The ground is fairly bare, mainly covered in woody debris and litter from the deciduous canopy above. There are some shrubs that dominate the area. Salmonberry lines the paths going into the wooded area at an average of 1.5 m tall. While there are some areas of invasive Himalayan blackberry, the main understory plants are native thimbleberry and sword fern.
Wildlife Trees and Large Woody Debris
Trees play a large role in forest even after they are dead. Standing dead trees house cavity excavators such as woodpeckers, squirrels and other cavity dwelling species. Red alder grows quickly, dies young and is easy to excavate, so it is an important source of wildlife trees in younger forests.
Wildlife
There are signs in this area that show that it is used often by wildlife. The sounds of birds lighten the canopy while the many worn paths indicate coyotes or other small mammals travel here. As well, excrement and markings confirm that animals are present. Look up, you may see a barred owl peering back at you from the lowest live branch of an alder tree! Click on the Play button below to hear what barred owls sound like.
Critical Thinking
How is red alder being used on the UBC Farm?
Why do you think few other tree species naturally seeded into this area?
Do you see any other remnants of the tree nursery that once bordered this area?
What would be the primary reason for alder trees dying in this area?
What contributions to the site do red alder bring? to the soil?