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Prior to heading into the field on May 26, 2019 I came up with a rough plan of action. I decided to split my 2 15 acre sections into 3 plots per 15 acres. All plots being roughly 5 acres apart. I randomly selected a number (5 meters) as a radius to survey per plot. This allows for a very wide span of the 30 acre property. I have attached photos of my three pages of field notes, and a few photos of some of the plots found. Based on my little research on the Giant Hogweed before my field work I would hypothesize that I will only find them in the bottom 15 acres of my property, as it is a ‘disturbed’ site, where as the back 15 acres are a higher elevation as well as it is heavily forested. It is very possible that my hypothesis could be wrong, as the seeds of the Giant Hogweed can travel hundreds of meters, and with enough light could potential begin to grow in the forest.

To obtain information on the Giant Hogweed I was required to do some research. I will be reviewing information on Giant Hogweed in Canada as an invasive species. This information came from ‘The Biology of Invasive Alien Plants in Canada. 4. Heracleum mantegazzianum,” Sommier and Levier. It reviews on how it takes over including its effects on the environment and human health. It also speaks on the identification and nature of the plant, as well as give possible management options, etc.

This is an academic, peer-reviewed material. https://www.nrcresearchpress.com/doi/pdf/10.4141/P05-158

In the last 3 pages of their review is a long list of sources sited in the text. They do not run their own tests, but rather review many others.

I have decided to my project on my own private property, located in Southbank, British Columbia, Canada. Southbank is a small remote rural area, about 24 km from Burns Lake, BC. There you will reach the ferry terminal of the Francois Forester that crosses Francois Lake to Southbank. Francois Lake is the 2nd largest natural lake in British Columbia. Our property is on the first street bordering the lake (we are on the upper side of the street, so our land does not sit directly on the lake shore).  For the purpose of this study I have split the 30 acres into 2 separate sections to study and observe.To make things simple, I divided the property in half. The first 15 acres (Section 1) is the home front. It is mostly grass land and was select logged around 10 years ago. To break down section 1 there is around 1 acre of mature birch and aspen stand, 3 acres cleared (home, yard, etc.), 5 acres new immature growth (aspen, birch, cottonwood), and the remaining 6 acres is grassland. The second section is a mature mixed forest stand (birch, pine, spruce). 1/4 of the back property is made up of a steep gully. The entire property is on around a 30% slope. The first site visit was May 25, 2019, spring/summer time. The temperature was around 20 degrees Celsius, at 1015. It was sunny with a slight breeze. I began to notice the abundance of young Giant Hogweed (Heracleum mantegazzianum). Giant Hogweed (also known as cow parsnip), is a prennial plant and often grows around roadsides, ditches, and streams.  It is an invasive plant and is know to commonly invade old fields and native habitats (woodlots). Their seeds remain viable in the soil for 15 years and each plant can produce up to 120000 winged seeds, which helps them travel long distances in the wind and streams. Once I obtained this information I began to thing of 1.) How does Giant Hogweed impact the environment (Natural Resource Impacts)? 2.) Pre-Cautions? How does it affect human health? and 3.) How do we prevent further growth as well as safe removal and management?

Below are photos of the site, both section 1 and 2.

References: http://www.invadingspecies.com/giant-hogweed/

I was in a bit of rush to record my field data before autumn erased the data I was trying to capture and realized that I was about 10 samples short for a valid bivariate regression analysis so unfortunately, I have to add a caveat to results.  Like many science inquiries, this raised more questions for me than it answered.  The ecological conditions in the forest are more complex than a simple walk through the park suggests.  I cannot walk my dog through this portion of the forest anymore without thinking about the forest dynamics all around me.

The correlation between the data appears to be borderline and requires more in-depth analysis.  I expected a stronger positive correlation.  It is interesting to note the cluster that took place with the light intensity readings.  I am just guessing but this could be due to canopy openings are not as variable as they appear to the eye and form discrete opening sizes.  The one outlier defies explanation at this time.

It is common knowledge that plants need light, however, I am interested to know how strong the correlation is to the amount of available light and the proliferation of vegetation on the forest floor when the canopy has undergone a disturbance.  Additionally, the presence of pedestrian traffic through the study area ensures that there is continuous disturbance of the vegetation in the area of the footpath.  People routinely stray off-path, dogs run off-leash, and herbivores such as deer eat young vegetation as it develops.  These conditions offer benefits to invasive species as they can be found along any popular forest footpath in the area.  These factors probably have a major role in determining the overall composition of the ecological communities, but each community is primarily dependent on available light for photosynthesis.  Therefore, I believe that studying the relationship between light levels and amount of vegetation would provide an interesting insight into the revegetation in continuously disturbed areas.

Project Keywords:

Light-levels, vegetation ground cover, Human disturbance

My study transect followed a footpath through the park forest.  The segment of the path in the study area is roughly 200m so I decided that 20 stations at approximately 10m intervals would provide a good sample.  After recording weather conditions and time/date, I followed the following procedure at each interval.

1. Note interval station in Excel.
2. Record relative light level in Lux (3x)
3. Measure horizontal distance from footpath to significant change in elevation (not part of the study but I thought it might be interesting to collect this data)
4. Measure max height of vegetation 1m from path (again not intended to be part of the study)
5. Photograph the vegetation in the area perpendicular to the footpath.

Additionally, I took ambient light readings in urban areas, open areas and under full forest canopy to establish data boundaries.

The sampling strategy was efficient and didn’t cause any problems.  I was able to take the light reading in quick succession so that the ambient light would be fairly consistent and not changed due to time-of-day variation.  The photographic data collection was not as time-sensitive because of the colour and luminosity calibration which I included in each image.

Although plant height was extraneous to this study, I determined that there was some correlation between light levels and plant height but I have not completed the image analysis to comment on the central thesis of this study.