Field Training with plants at York University; European Buckthorn (RhaImnus cathartica) DBH and canopy coverage in Danby Woods

Methods & Materials:

In order to assess the relationship between European Buckthorn DBH and
distance to other same species, 10 tree samples were studied.

The survey was situated within the Danby Woodlot at York University (≈ 43.7735⁰N, 79.5019⁰W)

The weather on Thursday September 22, 2016 was very warm with periods of
sun and cloud. A very small amount of precipitation occurred that was
insignificant. Students sampled 10 European Buckthorn trees within the Danby
Woodlot and recorded DBH and distance from one sample to the next. Students
used a tape measure to measure the distance and DBH and recorded results in a
notebook.
Hypothesis:The diameter of Buckthorn tree samples in the study would be
dependent on the distance from other Buckthorn tree samples. Buckthorn tree
samples with large DBH measurements would also have a high percentage of canopy
cover. Large trees are likely to have more canopy coverage since they have more
leaves. Trees close to trees with large DBH will consequently have smaller DBH
measurements and a smaller percentage of canopy coverage since the larger
canopies restrict sunlight to the small tree specimens.
Predictions:1. Buckthorn tree samples near a Buckthorn tree with a large
DBH will have smaller DBH measurements

2. Large Buckthorn tree samples with large DBH will have more
canopy coverage

3. Samples with high percentage of canopy coverage will be
the larger of trees sampled in this study

Group Members: Krysten Zarivnij, Monica Matta, Vanessa Guo and Avani Abraham
Metadata:Attribute: Description

Buckthorn Sample:
Data was collected by sampling 10 adult European Buckthorn trees. Adult trees
were selected based on trunk size (more than 2cm) and height (more than 200cm)
Sampling took place at York University in the Danby woodlot.

DBH (cm): Diameter
at breast height was measured in centimetres using a measuring tape. The height
of measurement was approximate 1.3m from the base of the tree. This measurement
was a rough estimate of the diameter of the trees trunk.

Canopy Coverage (%):
Canopy coverage was measured by shaking the tree while all group members
watched how much of the canopy moved within eye view directly above head. A
rough percentage was assigned to each tree canopy. Canopy coverage estimated
the amount of leaf cover in the sky directly above the tree of interest.

Distance between
samples (m): Distance from one European buckthorn sample to the next was
measured in metres using a taut tape measure.