Lab 11: Coastal Forest Virtual Field Trip
British Columbia’s coastal forests are some of the most productive in the world. The mild rainy winters sustain, in particular, the regional evergreen needleleaf (conifer) species that occur, and attain truly goliath proportions over their long lifespans. Coastal forests sustain a species-rich biota ranging from tiny edaphic (soil) organisms, to mammals, birds, and understory plants. Historically, the ecosystem included members of several nations of BC’s Coast Salish peoples (including the Musqueum, Squamish, Tsleil-Waututh Nations), who have lived sustainably in the region for millennia. Since European settlement, many coastal forests in the lower mainland region have been extensively logged and some converted completely to other human land uses.
This lab explores a large remnant of Coastal forest in Pacific Spirit Park, Point Grey, Vancouver, to examine its species composition, structure and dynamics, particularly in relation to human and natural disturbance processes. A set of 360° photos and videos (one in 360°) will be used to demonstrate the local species and landscapes. At the end of the lab, students should have an appreciation for the main species present and the sorts of processes that affect coastal forest dynamics, both natural and human-caused.
After completion of this lab, you will be able to:
- Become familiar with the species composition, structure and disturbance ecology of BC’s coastal forest ecosystems via an immersive digital experience.
- Use a dichotomous key to name and identify tree and shrub species present in coastal forests.
- Make field observations of forest stand structure and species composition and apply these to infer disturbance histories and predict future changes.
- Appreciate some techniques for studying forests, including tree-ring dating (dendrochronology).
- Learn about and identify some of the woody invasive species that have been introduced into Vancouver’s Pacific Spirit Forest and other local ecosystems.
- Consider some of the forest management practices of Indigenous peoples in the region and how these practices contrast with those of modern settlers.
In order to complete this lab, some background information in forest ecosystems, plant succession and disturbance processes is required.
Forest Ecosystems, Ecological Disturbance and Plant Succession
Read the textbook sections that review background concepts of forest structure and dynamics and concepts of ecological disturbance and succession. An overview is provided below:
Disturbance is a pervasive process in ecosystems. In the context of vegetation dynamics, it may be defined as any event that destroys part or all of the above ground vegetation in an ecosystem. Disturbance includes wildfire, flooding, large scale disease outbreaks, and major windstorms. Once viewed as a negative force acting on ecosystems, disturbance is now recognized as integral and essential to the function of many ecosystems. In forest ecosystems fire is often a critical disturbance. It has been a regular feature of BC’s dry interior ecosystems and even to some degree in the wetter coastal regions of this field trip. Fire adapted species require regular, frequent fires to remove competition, prepare the soil for their seed by removing litter and, for some conifers, provide the intense heat needed to open cones and release seeds. Without periodic fires, species in fire-prone ecosystems would gradually be replaced with less fire-adapted species.
For millennia in North America, wildfires were ignited by lightning or indigenous peoples. However, European settlers engaged in fire suppression in many ecosystems for decades. Thanks to growing scientific evidence, land managers now recognize fire’s role and, over the last several decades, have begun to implement “controlled” or “prescribed” burns to restore this critical ecosystem process. Nevertheless, catastrophic fires have becoming increasingly frequent and intense in recent years due to a combination of factors, including previous fire suppression and buildup of dead wood that increases fuel loads, as well as hotter, drier conditions and insect outbreaks associated with climate change. Although these newsworthy catastrophic fires have had tragic consequences for human populations, fire must be recognized as a critical ecosystem process in many systems, and considered in conservation and management agendas (Hewitt in Arbogast et al. 2018).
Plant succession refers to gradual changes in plant community composition and structure that occur following large-scale disturbance (e.g., fire, logging or cultivation) or on areas of new terrain (e.g., recently exposed glacial till, lava flows). Initial colonizing plant species are referred to as “pioneer” species. These are plants that arrive quickly via effective seed dispersal or that are adapted to grow rapidly in the open, well-lit conditions of early succession. Other names for pioneer species include r-selected species or r-strategists, and early-successional species. They may contribute to the establishment of additional species via root penetration and the cycling of organic material and minerals in the soil, though their role may be less pivotal in facilitating subsequent plant populations than once assumed. Later in succession, additional plant species establish populations as their seeds arrive from neighbouring sites, or, if the substrate is intact (e.g., following fire), as they emerge from buried seed and vegetative plant parts in the soil. In time, trees and shrubs mature, casting shade and altering the microclimate at ground level. The changes in humidity and soil temperature create conditions for shade-adapted understory plant species to establish. If major disturbance such as fire or human activity does not occur, an increasingly complex community structure may develop, and species more adapted to recruiting in shady understory conditions may dominate. These mid-to-late successional species are sometime categorized as k-strategists (and even “climax” species).
Succession was previously considered a relatively predictable process in which a sequence of plant communities replaced one another in a unidirectional fashion, with a stable endpoint called a “climax” community. Today, it is recognized to be a much less orderly process. The particular sequence of changes may be random as a result of stochastic processes such as dispersal that affect which species will establish. Patterns of succession may vary even across similar sites within one ecological region. Further, given the prevalence of disturbance, succession may be interrupted and “reset” frequently, for example in fire-prone ecosystems, so there is no guarantee that the elusive “climax” community will take hold. Thus, while this idea of a uniform, highly predictable successional process continues to be articulated in many university textbooks (Johnson and Miyanishi 2008), the evidence exists for a more stochastic, less predictable trajectory of change.
Background Information about the tour location
The Park was initially a part of the UBC Endowment Lands which were set aside in 1923 by the BC government to be used as a source of revenue for the fledgling University of British Columbia. Logging for export to European markets was the main revenue generator. Eventually, all but a narrow band of forest along the western tip of Point Grey was harvested. Today the forest is mostly second growth that established after logging or more recent disturbances. In 1975, the provincial government designated part of the UBC Endowment Lands as an ecological reserve and Pacific Spirit Park was established in 1989 (UBC Geography, 2019).
Vegetation and Soils
Both human activity and soils influence the tree and understory plant species across the park. Differences in the kind of past disturbance as well as the severity and timing, have contributed to the patchwork of varied plant associations throughout the park. The soils vary considerably among locations, although they are influenced by the same general climate and have common parent materials. Podzols underlie much of the Park and are characterised by a leached layer where minerals and decayed organic matter have been removed by rain seeping through the soil. Differences in soils between sites can be attributed to the growth and decay of organic material, which itself varies between sites based on local topography, the distribution of water and drainage of rainfall, and vegetation cover (UBC Geography, 2019). A video interpreting the soils in the Park in the second growth needle-leaf forest is available at UBC SoilWeb.
Dichotomous Key to Common Vascular Plants in Pacific Spirit Park
Download and view the dichotomous Key to Common Vascular Plants in Pacific Spirit Park provided with this lab (in Supplemental Materials, below). A simplified pictorial version of the key is also available for you, but you should be able to work with the language in the text-based dichotomous key. It is important to learn how to use a plant key and to become familiar with the vocabulary used to describe plants. The vocabulary is very specific to plant taxonomy and requires some attention.
In this lab, we begin by examining the forest stand structure and species composition of Pacific Spirit Forest along Spanish Trail. This lab consists of 4 exercises. Exercises 1-3 should take about 2-3 hours to complete Exercises 4 should take an hour or so.
BC’s original coastal forest ecosystems have been classified using the Biogeoclimatic Ecosystem Classification System (BEC zone). There are a couple of types of coastal forest. Identify the two main types, including the one where this tour is situated, and briefly describe them. This exercise should take 10-15 minutes to complete.
Step 1: Open Google Maps and enter these coordinates to locate the tour: 49°16’07.9″N, 123°14’09.5″W (49.268851, -123.235963).
Step 2: Go to the BC Climate Explorer website at: http://www.bc-climate-explorer.org/ (note – if window remains blank, set your internet browser for this site to “trusted”). If you wish, you may view the instructions (just first 55 seconds). Locate the tour area by zooming into the map near known features (e.g., coastlines, rivers, etc.) based on the location you have identified in Google maps. To zoom in on this website, you may need to double click on the map; to zoom out, you may need to use the command ‘-‘.
Step 3: In Climate Explorer, click “BEC UNIT” at the top under “Map By”. The BEC zone and subzone abbreviations will appear when you hover the cursor over the site location, e.g., “PPxh1” (short for “Ponderosa Pine Okanagan very dry hot”). Find full zone names at BEC Classification Reports. Navigate to the area of Pacific Spirit Park, using the landmarks on Google Maps.
- Record the abbreviation and full zone and subzone names for the following:
- Pacific Spirit Park tour site
- Another adjacent/nearby coastal forest type common in the region
Step 3: Go to Selkirk College’s online modules. Hover over the zone name to view the map; click on the zone name to see its description.
- Using the resource in Step 3, briefly describe the following:
- The climate conditions, including temperature and rain/snowfall conditions of the zone containing Pacific Spirit Park indicated in the Introduction for this zone’s page at Selkirk College’s online modules. A climograph of the region is available for your perusal here.
- The main ecosystem characteristics, and 3-4 of the major tree species found in this zone (2-3 sentences). Note that this zone is variable within, and you may not see all of these species along the tour.
Now that you are aware of the regional context, you are ready to begin the tour. It starts at the head of Spanish Trail where College Highroad meets Pacific Spirit Park as shown in the Google map, below. To zoom into the map, use the “+” icon. You may click the blue markers and a sidebar will appear with a brief overview of each stop.
NB: For a more immersive experience, at anytime you may try this interactive, 360 H5P version of the tour. Only the 360 photos and videos are embedded, however, so you will need to view the other learning materials (photos, text, linked resources) in the body of this lab.
Land acknowledgement: This tour takes place on the traditional, ancestral and unceded territory of the xʷməθkʷəy̓əm (Musqueam) People. We are grateful for the chance to study and enjoy this ecosystem, which they sustained for millennia.
Step 1: Watch this introduction video:
Step 2: Click and drag within the image below to explore the 360 photo at the Spanish Trail head.
As you learned in the video, the disturbance event that led to stand initiation here was a human-caused one. The site was cleared of trees, stumps and even topsoil, in 1952 to make way for a residential development. Clearly, the development plan did not go through, explaining why you see second-growth forest here, rather than apartments! Broadleaf, deciduous tree species regenerated spontaneously following the disturbance.
Step 3: Using the 360 photo, be a “field ecologist” and apply your observational skills, paying particular attention to visible evidence of:
- Species composition: inferred from, e.g., bark characteristics (color, texture/pattern); plant type, based on life-form by forest layer (shrub vs. tree; see Fig. 11.1, above), stem morphology and branch pattern, etc.
- Age structure: inferred from the range of stem sizes visible. Is this a stand with even-aged stems or one with stems in lots of different size/age categories? Note your responses.
Hardwood (Broad-leaf) Forest Stop (Stop 1)
Step 4: Watch the following instructional video:
Step 5: Click and drag within the image below to explore the 360 photo at Stop 1.
Here is the same scene in midsummer, June 17 2020, when deciduous trees had leafed out.
Ideas to consider before proceeding to the next step: Can you identify the two main species discussed in the video and shown in Figure 11.2? Use your dichotomous key to find their latin binomials and common names. Both species are early successional, and these individuals recruited shortly after site had been disturbed when there was no tree canopy, little competition, and ample light. One of these species is more abundant (common) than the other in this forest. You should be able to determine which by looking around the photosphere once you can identify each from its bark (see the video for clues) and other features, even without leaves on the trees!
What sorts of characteristics do you think these species have that allow them to arrive and thrive in recently disturbed sites (use your text as a reference)? These are adaptations – traits evolved over time, and they help to match the species with the type of environment (e.g., open, recently disturbed sites; shady, undisturbed sites) for which it is specialized. A few considerations:
- Seed size vs. seed numbers: there is often a trade-off between the size of a species’ seeds and the number it can produce with limited resources – species tend to fall into categories, either producing many-small, or few-large seeds.
- Seed dispersal characteristics: do the seeds have appendages such as plumes or wings to be scattered broadly by wind, or do they have tasty coverings to attract animal dispersers and be placed in specific locations? More importantly, how do these dispersal syndromes affect the chances of arriving and surviving in particular sites? Hint: species in the many-small seed category have a decent chance of at least some arriving in recent openings; species that produce a few large seeds have larger seed nutrient reserves to enable establishment in closed, shady sites where sunlight at the ground may be limited; at the same time, in these coastal forests, most tree species fall into the many-small seeds grouping. Nature often defies our simple attempts at categorization!
Are there other sorts of disturbances that might affect the forest? You might see some clues of more small-scale disturbance in the 360 photo. (Any broken branches? Signs of disease?) A discussion of disturbances, small and large-scale, should be available in your textbook or lecture notes.
How do you think this site will change in future? The answer will be relevant in the next set of Lab Exercises. Go to the next step for more clues.
Step 6: View the following video in which Kevin Pierce chats about clues that indicate how this early successional hardwood stand may change. Kevin is a UBC Geography PhD candidate and Teaching Assistant (2017-18) who led students on in-person field trips to this forest (shared with permission from KP; videographer, K Hurley, Mar 2019).
Step 7: Now watch this video in which biogeographer N Hewitt demonstrates how to date disturbance. In the video, a ring series (tree-ring core) is extracted from one of the largest, and oldest, stems at Stop 1. The ring counts and age of this tree tell how long ago it established, indicating the approximate timing of the disturbance event that led to stand initiation at the site (Note that this is species x – the one you were asked to identify first).
With this information and your dichotomous key in hand, you should be ready to answer the first few questions the next set of Lab Exercises.
Next, proceed to the boardwalk site….
Step 7: Watch the following video:
Step 8: Click and drag within the image below to explore the 360 photo of Boardwalk site [New Tab]:
Based on the information you learned, what sort of disturbance occurred here? How/Why? Hint: What do you know about Canada’s National animal (seen in Fig. 11.3)? What was the effect of this disturbance on the ecosystem and what sorts of species did it facilitate (allow to live here in its aftermath)?
Entering the Needleleaf Forest and a Look at some Recently Introduced Species
Step 9: Watch the following video:
In the video, a shrub species native to this forest, salal, was highlighted. Find out more about this and other native understory species, including Red huckleberry, Sword fern and Dull Oregon grape at Coastal Plants of BC videos, filmed here in Pacific Spirit Park!
Invasive species: Another species highlighted in the video is non-native. As you may infer from Figure 11.4, below, this European invader has been very successful at colonizing the hardwood forest, with several individuals visible in the photo. Consider the adaptations that have made it so successful in this ecosystem (what might they be?). Another introduced invasive species present in the park is European laurel (Prunus amygdala). Note that both of these European invaders are evergreen woody species adapted to environments with mild rainy winters, so they have been introduced in a place with a climate that closely matches their origin (you will revisit the issue of invasive species in the Reflection Questions, below). They also produce many berries that animals disperse. If you wish to explore the topic of invasive species, see e-flora BC’s Invasive plant species page (Klinkenberg 2020).
Needle-leaf Forest Stop (Stop 2)
Step 10: Watch the following video:
Step 11: Click and drag within the image below to explore the 360 photo of the needleleaf forest, Stop 2 [New Tab].
You have entered a remnant of a native coastal forest of the kind you identified using BC’s BEC System in 11.EX1. Notice the larger (and older) canopy trees relative to those in the hardwood forest, indicating the longer time since major disturbance. This stand established following logging and burning in the 1920s, regenerating naturally thereafter (planting or seeding later become common practice in clearcut sites in BC).
Consider the kinds of site conditions present here: cool and shady or hot and sunny (which?). How do they affect the sorts of species growing here (and visa versa)? Identify the three conifer (needle-leaf) species discussed in the video based on their leaves and bark, using your species id key. You will come back to this in 11.EX3.
Other native species in this forest include the small understory Acer (maple) species mentioned in the video. There is also a canopy species of maple with very large leaves (see your key!). The latter, large-leaved maple, is sort of a co-dominant species in this forest. It is shade-tolerant and reaches the canopy alongside the 3 conifers in late-successional stands. Find both in your dichotomous key; for precise botanical information on the understory maple species, watch this Coastal Indicator Plants of BC video. Now, you may wish to try this tree species id knowledge test.
Notice, in the 360 photo, the large pile of earth with young hemlock trees (saplings) growing on it along the east side of the trail (opposite from the dog). This is a tree-fall or tip-up mound, an important micro-habitat and “safe site” for many forest species, Red huckleberry and Western hemlock, for instance. Safe sites refer to areas protected from hazards (e.g., burial from leaf-litter) and providing suitable conditions (fresh, exposed soil) for species’ seed to germinate and establish. These sorts of micro-habitats become more available in complex environments such as this, where forest trees have had time to live out their life cycles, decay, and created decomposed stump or branch litter, etc.
More about Pacific Spirit Forest, Past and Present:
This area, like the one at Stop 1, experienced large-scale human disturbance, in this case, by extensive logging/tree-cutting, but less recently. See a photo of what this must have looked like at this link (clearing of Point Grey, 1914, UBC Archives). One may assume that the forest is approaching a size (age) structure and species composition of a late successional stand, perhaps one that more closely resembles the historical forest, common throughout the region prior to European settlement. Successional changes have thus proceeded for longer than at Stop 1, and this greater time since disturbance helps to explain the difference in species composition and structure between the two sites. That said, it probably lacks the complexity and very large, old (>500 years age) stems that might have occurred otherwise on sites that escaped periodic fires.
There are other sorts of disturbance here including some more regular, small-scale disturbance. When we take students through this site, we pass some burned out stumps (remember this for 11.EX3, Question 11).
Think about the forest before the logging event. It would have supported stems much more massive than those present (Fig. 11.6).
Stumps associated with these wide-scale logging events are found throughout Pacific Spirit forest (Fig. 11.7). How do you think the university’s extractive forestry practices affected the ecosystem? Would there have been long-term impacts on structure and function? Of course, disturbance and change is a normal feature of ecosystems, but perhaps the scale of destruction from logging operations was atypical? In this sense, this little piece of needleleaf forest represents an altered remnant, and may be illustrative of the “Anthropocene”.
Consider how post-settlement forest practices compare to those of the original people of Point Grey, the xʷməθkʷəy̓əm (Musqueum). One Indigenous practice of forest harvesting, cedar bark stripping, was touched on in the video. This was non-destructive: Trees survived, gradually sealing off wood where bark was stripped via cambial tissue growth (growth from cambial cells located just beneath the bark that produce the tree’s annual rings). Affected trees retain residual scars that identify them years later, and are referred to as “culturally modified trees” (CMT).
Stop #1. Broadleaf Forest
- For the dominant tree species, identify the species and give both its common and scientific name. Note: it is scientific protocol to either underline or italicize scientific names. Genus names are capitalized and the species names are lower case.
- Common name of the dominant tree.
- Scientific name of the dominant tree.
- List two diagnostic features from the key that you found most helpful to identify this species.
- What was the main disturbance that initiated this broadleaf forest?
- Based on your observations, list two other disturbances (besides the hiking trail) that appear likely to have occurred in this forest and provide evidence for each one.
- Name the pioneer tree species in this forest and describe at least 2 specific attributes (adaptations) that help it to be an effective pioneer species?
- Based on your observations, how might the broadleaf forest change in the future, assuming it continues to undergo succession without any further major disturbances? State two possible ways the forest might change or develop.
- The trees in this forest are deciduous and lose their leaves each autumn. Do leaves contribute to organic or mineral soil horizons or both? Briefly explain.
Stop #2. Needleleaf Forest
- Use the Key to Common Vascular Plants in Pacific Spirit Park (Supplemental Materials) to identify three common tree species in the needleleaf forest. Give both their common and scientific names. Explain at least one diagnostic feature you found most useful in identifying each. These could be features mentioned in the video or observed on the specimens and seen in the key.
- Name the two maple species mentioned in the materials above, and in the videos. Identify which is a small understory species and which is emergent, in the canopy.
- Name the dominant species (one or potentially more). Briefly explain what information you based this assertion on (what did you observe in the photospheres and/or video to suggest that this was the case)?
- Based on your observations, list two disturbances that have occurred in this forest and suggest why you listed these. What information did you notice/draw on?
NB: Were we to continue down the trail a few metres, we would arrive at the site of a charred tree stump. Other sorts of small- and large- scale forest ecosystem disturbance types are discussed in your course readings and in this Natural Resources Canada page (in particular, the literature cited list).
- In the needleleaf forest stand (at Stop 2) we touched on a few characteristics, or “ecosystem properties” that occur in these less-recently disturbed sites, and are important from a biodiversity standpoint. Describe one characteristic/property and explain why it matters from an ecosystem or biodiversity standpoint.
- If disturbance occurs and creates large canopy openings, which tree species do you predict will colonize the openings. Justify your choice (there are two possibilities. One of them is growing in the canopy at this site, and acts as a sort of “pioneer species” in large openings in this otherwise mature forest).
Questions 1-4; 6-8; 10-11 adapted from UBC Geography (2019).
Get to know some of the species of tree growing near you: Identify two species in your immediate landscape (garden, along your street, in a park or nature preserve or outdoor recreational area you visit). Here are the steps:
- Find species: Criteria to look for:
- Tree species (not shrubs/herbs/ferns).
- At least one should be a coniferous/needle-leaf species. See your dichotomous key to ensure you find one.
- At least one should be a broadleaf/hardwood tree. See dichotomous key for indicators
- Note that a common street tree in North America, and native to Asia, Ginkgo biloba, is not a broadleaf / hardwood (angiosperm) – it is taxonomically related to needle-leaf / conifer (gymnosperm) species, but its appearance is deceiving!
- Identify and document your species: List the names, both scientific and common, for each of your species and take a photo of the leaves and bark / any cones or flowers/seeds to include in your submission
- Indicate the species’ origin: State whether the species is native to your location or non-native and if the latter, where it originates.
- Estimate its commonness/abundance in the local landscape: State whether it is one you have noticed frequently in which case it may be labelled abundant/common in your location, whether it is not common, or you “don’t know” (since this information is often complicated by human land management and cultivation practices and may not be easily determined).
- Note other relevant details, e.g., any of the following which apply: Is the individual you saw cultivated (planted) or wild (recruited naturally). If the species are native to your area, can you specify its niche or role in the local ecosystem? If non-native, how do you think it got there – intentionally (brought in to be planted/cultivated) or unintentionally. Provide brief notes to explain your reasoning.
Length: 1 short paragraph per species, plus photos.
Tips for finding species information: The Key to Common Species in Pacific Spirit Park (or pictorical version of the dichotomous key) will assist you in distinguishing needle-leaf and broad-leaf species, but if you are not in BC, clearly the taxa will differ at the species and possibly genus level. If you are unable to determine species’ identity with reference to online guides, take a photo with your phone and use one of several apps, including iNaturalist (at: Google Playstore; App store) to identify it. To find whether native or non-native to your region, there are many online sites such as e-flora (here for BC; or search for other parts of the world using scientific or common names). Wikipedia is often reliable (though no guarantees with crowd-sourced information!). If you have trouble finding information, ask your TA/Instructor for assistance.
- How did the species you identified in the needle-leaf forest compare to those you noted from the ecosystem classification for this BEC zone (in 11.EX1)? How did the species composition differ (indicate any species in the BEC zone description that were present and ones were absent or in addition to what you had expected). What might account for these differences (ecosystem controls, and factors that determine plant populations)? Note that “randomness” is a factor influencing plant populations and patterns of species distribution!
- One of the woody species we glimpsed in both forest types is an introduced species (see the video filmed as we enter the needle-leaf forest). It is known for its evergreen leaves with pointed edges and for its red fruits. Use the key to identify this species. Name the species and state which world region it originated from. You also learned of at least one other introduced species on the tour. What impact do these sorts of invasive species have on native species in the forest? What actions do you think could be taken to manage invasive species and the threat they pose to biodiversity? (one paragraph with the species information and your thoughts)
Key to Common Tree Species in Pacific Spirit Park
Download the Key to Common Species in Pacific Spirit Park and print or open it on your computer. A key is a tool for identifying plants. Characteristics of the plant are described in couplets (e.g. 1a and 1b). For each species, only one of the two statements is accurate. For each accurate description, follow the instructions indicated in the right column; continue to the next pair of couplets or note the identification of the plant. Ultimately you will determine the genus and species of each plant using this key or by referring to other field guides. Remember to follow protocol when using scientific names of plants. *indicates non-native species.
The pictorial key is also available for download here, but it is good practice to become accustomed to operating the more detailed text version above.
Illustration of Useful Terms
Simple: a broadleaf, with only a single blade and is joined by its stalk to a twig or branchlet that is woody.
Compound: a broadleaf, with several distinct leaflets attached to a midrib that is not woody. It is the stalk of the midrib that is attached to the woody twig.
Leaflet: leaf-like subdivision of compound leaves (see above), species usually have a characteristic number of leaflets per leaf.
Alternate: leaves (simple or compound) are arranged singly at intervals along the twig.
Opposite: leaves (simple or compound) that occur in opposing pairs along the twig.
Lobed: a leaf with incompletely separated, rounded or bristle-tipped sections.
Toothed: a leaf having large, dentate or serrate teeth at its edges.
Palmate – leaf structures (e.g., veins or leaflets of compound leaves) radiating out from a common point
Pinnate – leaf structures (e.g., veins or leaflets of compound leaves) distributed along a central line
Branchlet: the end portion of a branch containing the previous year’s growth
Hewitt, N. in Arbogast et al. 2018. “Discovering Physical Geography”, Chapter 10: Plant Geography. 1st Canadian Edition, John Wiley & Sons, Toronto
Johnson, E.A. and K. Miyanishi. 2008. Testing the assumptions of chronosequences in succession. Ecology Letters 11:419-431.
Klinkenberg, B. (2020). Invasive Plant Species. In: Klinkenberg, Brian. (Editor) 2020. E-Flora BC: Electronic Atlas of the Flora of British Columbia [eflora.bc.ca]. Lab for Advanced Spatial Analysis, Department of Geography, University of British Columbia, Vancouver. [Accessed July 23 2020]
Straley, G.B. and R.P. Harrison. 1987. An Illustrated Flora of the University Endowment Lands. Botanical Garden, Technical Bulletin #12. University of British Columbia, Vancouver BC
UBC Geography (2019) Lab 4 Handout: Soils, Tree Species Composition and Disturbance History in Pacific Spirit Park. In GEOB 102, Our Changing Environment: Climate and Ecosystems, Dept. of Geog., UBC
Key to Common Trees in Pacific Spirit Park adapted from Straley, G.B. and R.P. Harrison. 1987. An Illustrated Flora of the University Endowment Lands. Botanical Garden, Technical Bulletin #12. University of British Columbia, Vancouver B.C.
Combined Media Attributions
- Figure 11.2
- Left image: Red Alder Leaves by the US Bureau of Land Management is in the Public Domain.
- Inset image: Male catkins with tiny catkins by Walter Siegmund is licensed under a CC BY 2.5 (Attribution) license
- Right image: Seeds and fluff of cottonwood by Amiyashrivatstava is licensed under a CC BY-SA 3.0 (Attribution ShareAlike) license
- Figure 11.3
- Left image: Typha angustifolia Narrowleaf Cattail by Fritzflohrreynolds is licensed under a CC BY-SA 3.0 (Attribution ShareAlike) license
- Middle image: American beaver tree-cutting by D. Gordon E. Robertson is licenced under a CC BY-SA 3.0 (Attribution ShareAlike license
- Right image: Green frog by Samantha Peng and Nina Hewitt, August 2018, is licenced under a CC BY-NC-SA 4.0 (Attribution NonCommercial ShareAlike) license
- Figure 11.4
- Left Image: Illustration Ilex aquifolium0 is in the Public Domain.
- Right Image: Photo by N Hewitt is licensed under a CC BY-NC-SA 4.0 (Attribution NonCommercial ShareAlike) license
- Figure 11.1 Eastern Forest Profile © Sara Hewitt-Wood is licensed under a CC BY-NC-SA (Attribution NonCommercial ShareAlike) license
- Figure-11.5 Coring Doug fir © Kevin Pierce and N Hewitt is licensed under a CC BY-NC-SA (Attribution NonCommercial ShareAlike) license
- Figure 11.6 Logging, Lower Columbia River, ca. 1905 © J.F. Ford is licensed under a Public Domain license
- Figure 11.7 Stump with notches © Nina Hewitt is licensed under a CC BY-NC-SA (Attribution NonCommercial ShareAlike) license