Category: Percy Hebert

The organism that I would like to study is the Wolf Willow (Elaeagnus commutata). I chose three areas that are along the Bow River in the southwest of Calgary, Alberta that have a large population of E. commutata. The first area (1) was between two pathways, and a medium distance from the river; the second area (2) was at a much higher elevation than the river, close to the river; and the third area (3) was at a higher elevation than the river and far away from the river.

The plants that were closer to the river in area 1 appeared to be taller, and still had some berries present on the tallest branches. I didn’t bring a measuring tape but the plants here are taller than I am, so they are at least 6’ tall. The plants in area 2 were around 4’ tall, and much more abundant than either of the other areas. Only a few scattered berries were present, again on the tallest branches. In area 3, the furthest from the river, the plants were quite short – only around 2’ – and there were no berries present.

It’s unusual to see berries on plants during winter, but the wolf-willow’s berries seem to remain throughout the winter and into the spring. They are a pale silver colour.

From these observations I hypothesize that the growth of E. commutatais heavily reliant on a nearby water source. I predict that the tallest E. commutataplants will be in close proximity to the river. The responding variable would be the average height of the plants, which is a continuous variable. The explanatory variable would be the adequate water present in the form of the Bow River.

The organism I have chosen to study is the Western Sword Fern (Polystichum munitum), a common fern found in the Pacific North West region.  The fern is commonly found in moist, mild and shady environments.

The reason I decided to study this organism is that it is commonly found throughout Pacific Spirit Regional Park, however there were some locations on within the gradient of study that I observed fewer sword ferns present. At the creek site (Site 2), on the west bank of the stream there were fewer ferns, however on the east bank of the stream there were many more. The ferns at the interior site (Site 1) appeared to be more vigorous and larger than the ferns at site 2. Site 1 is located amongst large coniferous trees and it appears that less light makes it through to the forest floor. This is an environment that would suit sword fern growth so I would predict that the ferns may grow more vigorously or have greater abundance at this site compared to the creek site (site 1). The banks of the creek are relatively open to the sun as the creek runs south and the trees at the edge of the forest have been thinned or cleared as the creek passes beneath the road. I would expect that this site, although moist, the sun exposure may affect the sword fern growth. I did notice that the ferns were more prevalent on the east side of the creek than the west side, and again this may be due to the sun exposure the different banks experience.

I hypothesize that the fern growth will be greater in the more shady areas of the forest as measured by crown count per unit area, and frond length. I am also interested in counting the density of spores to determine if that also varies by site. The explanatory variable will be the amount of light at each site classified as high and low. The response variable of crown number/ plot and frond length will also be continuous variables.