Teacher s Toolbox. A Forest Ecosystem Education Guide JUNIOR/INTERMEDIATE. Forestry Guide

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1 Teacher s Toolbox Forestry Guide This toolbox is intended to assist teachers in using resources that introduce forests into the classroom. Each section has related Focus on Forests resources suggested as accompaniments to the subjects. JUNIOR/INTERMEDIATE A Forest Ecosystem Education Guide Activities and For Teachers and Resource Educators

2 Forests For Any Subject Whether you are teaching history, math, music or science, the forest can fit into any curriculum!. Forest Regions 2. Forest Ecosystems 3. Biology of a Tree 4. Forest History 5. Forest Management 6. Forest Tools 7. Careers in the Forest 8. Changes in the Forest A Message From Focus on Forests Focus on Forests is a FREE, national, online resource that provides curriculum linked teaching resources to help introduce forests into the classroom. We are constantly adding new lesson plans, activities, fact sheets and videos to the resources, so make sure to check back often!

3 FOREST REGIONS Biodiversity Biodiversity (biological diversity) refers to the diversity of life on this planet- including different species of trees, flowers, insects and animals. A biodiverse ecosystem provides us with a healthy environment, clean air, productive soils, nutritious foods, and clean water. We depend on biodiversity for many necessities in life. There are several different forest regions across Canada. Different forest regions occur because of different soil types, climatic factors, water availability, and topography. There are 8 recognized forest regions in Canada: Boreal, Deciduous, Great Lakes- St. Lawrence, Acadian, Subalpine, Montane, Columbia and Coast. Each region has its own characteristic mix of tree species that thrive under certain growing conditions. Boreal Most Common Trees: White and Black spruce, Tamarack, Balsam fir, Jack pine, White birch, Trembling aspen Deciduous Most Common Trees: Sugar and Red maple, American beech, Red oak, Basswood, White elm, Tulip tree, White and Green ash, White pine, Black walnut, Red cedar, Hemlock Great Lakes-St. Lawrence: Most Common Trees: Sugar and Red maple, American Beech, Red Oak, Basswood, White elm Acadian Most Common Trees: Black spruce, Red oak, White elm, Beech, Red maple, Black ash, Trembling aspen Environment Canada Sub-Alpine Most Common Trees: Engelmann spruce, Alpine fir, Lodgepole pine Columbia Montane Most Common Trees: Blue Douglas fir, Trembling aspen, Lodgepole pine Coast Most Common Trees: Western red cedar, Western hemlock Forest Regions of Canada Fact Sheets and Activities Biodiversity Most Common Trees: Western hemlock, Douglas fir, Western red cedar, Sitka spruce 2

4 BIOLOGY OF A TREE When we look at a tree, we often only consider the parts that we see above ground. While the trunk, branches and leaves make up a large portion of a tree, a whole other part of the tree exists below ground. The root system is a vital part of the tree, supplying it with water and nutrients to help it grow. Without adequate growing space or the right type of living environment, a tree will not grow to its full potential. Activity: Ask your students to draw a tree. Have the students share their drawings. Observe whether students included all parts of the tree-including the roots. Discuss with students that the parts of the tree seen above ground are only one part of the tree, and that the structure below ground often determines how healthy a tree above ground can be. Crown The branches, twigs, and leaves, constitute the crown of tree. The branches and twigs hold the leaves up to receive sunlight, vital to food production. Germination A tree starts life as a tiny seed. Given the right conditions, the seed will start to germinate. The tree embryo absorbs water and splits the seed coat. First a tiny root grows and bends downward into the soil under the influence of gravity. Finally, the stem and leaves emerge from the seed coat and push their way through the soil toward sunlight. The seedling then begins to manufacture its own food. Eventually, it grows into a larger tree called a sapling. Trunk The trunk is the main stem of the tree. It has two main functions- to support the crown, twigs and leaves, and to transport food and water throughout the tree. The outer bark on the trunk protects the inside of the tree from injury and from drying out. It also acts as an insulator against cold and heat. Roots Roots spread in a vast and intricate network, like underground branches. They usually extend as far underground as the twigs spread in the crown of the tree. In addition to anchoring the tree in the ground, roots absorb water and nutrients from the soil. Not All Plants are Created Equal Let s look at trees Construct a Tree Seed Sort Seed Secrets The Wonderful World of Seeds Curious About Cones Winter: Choices to Make How Trees Grow Tree Waterworks /2 Fact Sheets Comparing Trees Parts of a Tree 3

5 FOREST ECOSYSTEMS Forest ecosystems are more than just a group of trees- they include a community of organisms both above and below ground. In old-growth forests, different canopies form creating a layering effect among the forest. There can be more than one layer formed by trees or shrubs in a forest. ABOVE GROUND Supercanopy trees: these trees poke out high above any of the others, and act as resting places or nesting sites for birds. (ex. White pine are distinctive in their supercanopy reach) Canopy trees: mature trees form a continuous layer that creates shade below. Understory trees: small tree growth beneath the canopy trees, with slow growth rates as a result of limited sunlight resources. Gaps in canopies often cause these trees to grow quickly when sun becomes available. Shrubs and saplings: grow in the shade of mature canopy trees and in open areas. Decaying wood: dead trees fall to the ground, but do not finish their role in the ecosystem. Decaying wood plays an important role in wildlife habitat, nutrients and habitats for other plants. Ground cover: a carpet of different species can be found on the forest floor including mosses, ferns, tree seedlings, flowers and fungi. Organic Litter: along with decaying wood, leaf litter also plays an important role in returning nutrients back to the soil. This layer helps to retain moisture in the soil, and provide habitat. Cavity Trees and Snags: Cavity trees are living or dead trees with holes; snags are standing dead trees. Both of these provide important habitat and nesting features for lots of animals like owls, woodpeckers, small mammals and bats. BELOW GROUND This is not an easy part of the forest to see, but plays one of the most important roles. Large and small roots of trees and plants intertwine themselves throughout the soil. Different soil layers make up soil horizons. At the top of the soil layers is the organic layer, made up of dead leaves and plants. Below this is a dark layer made up of decomposed plants, and where you will often find fine plant roots. Each year the forest sheds leaves, twigs, and branches to the forest floor. Decomposition will break these pieces down to add to the soil. 4

6 Succession Succession is the natural process of change that occurs in a forest over time as one community of living organisms replaces another. When a forest is disturbed (naturally or through harvesting), it begins to change right away. New plants germinate, grow and reproduce to successfully inhabit the vacant ecological niche. As the plants increase in size and in number, competition and environmental change begin to change the ecosystem. A new series of plants germinates, grows and reproduces to repeat the cycle of change. The rate of change becomes more gradual with time until there appears to be no change. This is the final stage of succession in the ecosystem and is called the climax. However, it must be emphasized that forests are dynamic communities that are continually evolving at varying rates. Even a climax community is constantly undergoing changes. At any time in the series of changes from the beginning to the climax, a new disturbance may interrupt the series and create a new beginning. There are two major forms of succession: primary succession and secondary succession. Primary succession begins on bare areas that did not previously support vegetation growth. These may be areas of water, sand, or rock. Primary succession begins with soil building. Soils develop from primitive plants called colonizers reacting with the rock over long periods of time to eventually provide bits of soil that in time will support larger vegetation. With the accumulation of soil, new plants germinate, grow, and reproduce to begin the stages of a new succession. Secondary succession occurs in areas in which vegetation does grow, but which have been altered by such external forces as fire, logging, and land clearing. New vegetation is able to establish on a previously initiated succession that was interrupted by fire. New plants germinate, grow, and reproduce to begin the cycle to the forest stage. Timber harvesting is another example of a disturbance causing secondary succession in a forest. How Trees Grow Nature s Throwaways From Buds to Leaves Stumped Invent a Forest Creature Exploring Ecosystems Cutting Styles Reforestation Forest Succession 5

7 FOREST HISTORY Canada s history is strongly built around forestry. Prior to the settlement of Europeans, First Nations impacted the forest through slash and burn that removed trees to make room for agriculture opportunities. Removal of wood was limited, and had a very small impact on the forest. First Nations still have an intimate and important connection with forests and forest resources across Canada. The arrival of European settlers brought more intensive logging practices to Canada s forests. The French were the first of the European settlers to depend on the forest as a source of income. However, their dependency was not exactly on the timber of the forest, but rather the animals inhabiting them. Their major source of income came from the fur trade, and wood was harvested at a small scale, primarily for local heating and ship and house building. It wasn t until the early 9th century that Canada s forests began to suffer devastating losses of trees. The war between Britain and France had cut Britain off from its timber sources along the Baltic Sea; therefore, Britain strongly depended on the forests in Canada (then still a British colony) as a source of materials for naval shipbuilding. Although pine and oak species were the main harvesting targets, many other species suffered due to the logging practices and techniques applied to the forests in those times. The term logging refers to the cutting, processing and removal of trees from a forest, and in the early 9th century, this was mostly done by hand and horses. Cut trees would be pulled out of the forest by horses, and then hewn (cut and shaped with a small sharp object), usually into square beams. However, in order to remove these trees, much of the forest had to be converted into logging roads, which was the result of poor forestry practices. Most of the cleared areas were then converted into agricultural fields or settlement Picture Source: areas. You can look at a forest for signs of the past. Tree rings tell an important history of the area. A tree ring (also known as a growth ring ) is the result of new growth in the vascular cambium. Visible tree rings are a result of the change in growth speed of a tree, with each ring representing one year in a tree s life. One can measure the age of a tree by counting the number of rings formed in the trees trunk, which is known as dendrochronology. The newest ring formed in each tree is adjacent to the bark, and represents the last growth. Each tree ring has a line between the late wood (dark), which grew at the end of the previous growing year, and the early wood (light), which grew at the start of this year. Tree rings vary in size based on conditions for growth in a season or year. Larger tree rings generally represent a more productive growing season, and smaller ones represent a poorer growing season. Dendro Discs Life History of a Tree 6

8 FOREST MANAGEMENT Forest management consists of a number of steps that occur in a sequence and are repeated at intervals. Whatever their origin and size, the designation of the forest area that is under a specific management plan is very important. Forest management is often confused with logging of a forest, which is usually replaced with the term harvesting. Harvesting is only one part of forest management as a whole, but it attracts the most attention because it causes the most visible change to a forest s structure. Steps:. Commitment Forest owners and managers develop policies that outline the degree of their commitment to sustain forests and practice long-term forest management. 2. Public Participation General concerns about forest management and activities, and their impacts, are raised on a regular basis, and public participation in the planning stages of forest management has been adapted in many provinces. Most of these concerns are raised by individuals or organizations in local communities, which may include: foresters, engineers, trappers, aboriginal people, recreational users, and many more. 3. Planning Forest management plans are prepared based on a given province s forest management manual. Most of these include: i. An updated description and inventory of the proposed area and longterm activities (usually 5-25 years), along with the objectives, goals, and values that are to be met a specific times. ii. A summary of the management strategy and how the objectives will be met. iii. Work schedules providing activities, dates, and locations to meet the objectives of the management plan. The fundamental part of a forest management plan is to determine the annual allowable cut (AAC) (how much timber may be harvested per year). The AAC is determined based on a forests growth over a full rotation (about 80 or more years), and must take into consideration the productivity, capacity, regeneration, and nature of the forest. The AAC is re-assessed at each periodic revision as signed in the plan, and will vary based on the depletion or re-growth of the forest. 4. Implementation and Assessment of the Plan There are three important steps in the implementation of a plan i. Access There must be access to the forest in order for any activity to take place (access is commonly by road). Planning the type and location of access is crucial, and it involves looking at: the cost; potential environmental impacts; and effects on values, uses, and other users. 7

9 ii. iii. iv. Harvest Once there is access to the forest, the removal of timber begins. There are four main systems of harvesting trees: seed tree, shelterwood, selection, and clear-cutting. The selection of any system is based on how suitable it is for a given location and scenario, and there are many variations of each system which often blend into one another. The most important thing is to choose a system that meets the objectives of the forest management plan. Regeneration The most important part of any management plan is to re-establish a harvested area with new trees. This is accomplished either by tree planting or natural seeding. For successful regeneration to occur, the planting sites and seeds must be prepared (preparation involves creating suitable conditions on the forest floor for regeneration, and varies by location and harvesting system). Maintenance The forested area must be maintained and protected in order to promote forest health and meet the objectives of the plan. Usually, thinning (removal of unwanted trees and plants) occurs to promote the growth of healthier and more desirable trees, and to reduce competition within the stand. 8

10 Forestry Guide Ownership and Governance of forests vary per province. Table. Distribution of ownership of Canada s forest lands (total forest area [millions of hectares] and percent ownership) (Source: Canadian Forests: A Primer, 999) Province/ Territory Total forest area (millions of hectares) Federal % Provincial/ Territorial % Private % British Columbia Alberta Saskatchewan Manitoba Ontario Quebec New Brunswick Nova Scotia Prince Edward Island Newfoundland and Labrador Northwest Territories Yukon Canada Paths to the Forest Balancing Act Reforestation Fire Feelings Cutting Styles A Fine Balance The Choice is Ours Private Woodlands: Challenges and Solutions Fact Sheets Silviculture Clearcutting Forest Management 9

11 FOREST TOOLS Forest Inventory Understanding what is around you helps to determine the choices you make in forest management. The best way to achieve this is by taking measurements of the forest to get a good picture of what planning should be done for that piece of forest. Forest inventory focuses on taking several important pieces of information including tree species, age, height, density, and girth. Tree Identification Canada has hundreds of tree species that span the country. Greater diversity of species coincides with different environmental factors including water availability, soil type and climatic factors. Trees can be identified into deciduous (trees with leaves) and coniferous (trees with needles and cones). Activity: Take your students outdoors to identify trees, either in a nearby woodlot, or on the street. Compare the amount of native vs. nonnative tree species you identified and where they were most commonly located (i.e. owners front lawn, public stree tree, woodlot, etc.) Clinometer Scaling a tree or cutting it down may be the most accurate way to measure the height of a tree, however not the most practical. Good ol trigonometry is the best way to estimate the height of a tree. By using angles and distances, you can get a pretty good estimate of how tall a tree is. A fancy tool, known as a clinometer, measures the height of a tree at certain distances from the base of the tree. Looking through the small window, gives you an instant reading of the estimated height. Don t have a clinometer? No problem, check out the Measure the height of a tree activity sheet and learn how to measure the height using a ruler! Let s Look at Trees Mini-Forest in the Schoolyard Trees at Home (Ontario) Forest Regions of Canada Reaching New Heights 0

12 Increment Borer Every year a tree puts on a new layer of growth. By looking at a cross-section of the tree, you can easily count the rings to determine its age. An increment borer is a tool that drills a small hole into a living tree, and is able to remove a small section of wood tissue with minimal damage to the tree. Prism Prisms are tools used to determine the basal area of a forest. Basal area- the area of a section of land that is occupied by the cross-section of tree trunks and stems at their base. See the image to the right. If you were to add up the surface area of all of the trunks, you would get the basal area for a hectare. One looks through a prism to determine if a tree is counted or not. If the offset section of the tree (seen through the prism) touches the tree sections outside the prism, then the tree is counted. Otherwise it isn t. Diameter Breast Height (DBH) Diameter Breast Height (DBH) is a standard way of measuring the diameter of a tree to determine its growth and volume. It is approximately.37m from the base of the tree. There are two tools in which to measure DBH- a special DBH tape or calipers. These tools are already calibrated to give you instantly the diameter of the tree, with no calculations required. Understanding the diameter of a tree helps to determine volume by giving one part of a calculation for volume of a cylinder.

13 Forestry Guide FOREST CAREERS A career in forestry can be anything from working in the field, to operating machinery, to working as a lab technician on wood products! The possibilities are endless, and there is a wide diversity of careers growing every year! Forests, if well-managed, are a renewable resource, and contribute to Canada s economic, cultural, and social wellbeing. With the recent low enrollment into post-secondary forestry programs, along with the high rate of retirement in the forest sector, there has never been a higher demand for forestry professionals. Forest professionals understand the connections that people have with the natural environment and all it has to offer. These connections are linked to forests, ecology, wildlife, pest control, timber harvesting, non-timber wood products, and forest regeneration, to name a few. Since forestry is very interdisciplinary, it invites a wide range of individuals with an even wider range of skills, to work together and to promote healthy forests. Some careers may include: Registered Professional Forester Forest Technician Biologist GIS Analyst Conservation Officer Environmental Engineer Forest Folks Forest Careers Arborist Forest Operator Scientist Forest Fire Fighter Park Worker And much more! reers in a c t u o ab n more, visit r a e l o y T forestr rs.ca caree orest f. w w w Activity: Ask your students to write out a list of their skills. Based on these skills, have the students identify which forest career suits them best. Have them develop a poster which promotes their forest career. Ask the class to find other forest careers that they feel would work well with their forest career. Have one member from each group explain how each forest career in their group is linked, and compare among other groups 2

14 Forestry Guide CHANGES IN THE FOREST Climate Change Climate change is expected to have a significant effect on forest ecosystems. Deforestation and land conversion has decreased carbon removal from the earth s atmosphere that forests would have removed through photosynthesis. With an increase of carbon, and more specifically, carbon dioxide (one of the five major greenhouse gases in the earth s atmosphere), more heat is being trapped in the atmosphere instead of being emitted back, thus increasing the atmosphere s temperature and causing global warming. As temperatures in the atmosphere increase, significant changes will occur to the composition of forests. Species that adapt best to new climate conditions and disturbance regimes will succeed and dictate the transformation of forests. In some instances, forests may convert to different land types on their own, such as grasslands. The productivity of forests will vary (either increase or decrease) depending on the rates of tree growth and mortality, as well as the region. Many forested areas will experience a decrease in productivity, which may result in habitat loss, or a migration of species (usually northwards, or higher in elevation). Other regions will go through something called novel climate, which means that tree species that are already poorly adapted to climate change will experience even more stress. Forest-dependent communities will experience the impact of changes in forest regimes, specifically in timber supply alterations and other forest product (timber and non-timber) values. Both the quantity and quality of desired tree species will be affected, putting many forest-dependent communities at risk. Also, forest operations may be time-limited with the changes in season lengths. Shorter winters mean less time for harvesting operations in Canada. Aside from economic losses in forest value, increased fire activity will also influence communities directly and indirectly. It is estimated that annual burned areas will approximately double by the end of the century. 3

15 Invasive Species Invasive species are threatening our forests now more than ever. Global trade has made the introduction of pests and plants into Canada even easier. While there are protection mechanisms to prevent introduction (Canadian Food Inspection Agency), invasive species are still entering the forests and posing incredible threats to ecosystems and resources. An invasive species is an organism (animal, bacterium, fungus, or plant) that creates a negative impact on its surrounding environment. These impacts are social, economical and environmental, and have an influence on human health. Invasive species are commonly associated with the terms non-native, alien or introduced (all of these terms refer to a species that does not naturally occur in a given area); however, that is not always the case. Given the right influence of events, certain native species may outcompete other native species, and be considered an invasive species. Environmental and Economic Impacts With the alteration and disruption of natural landscapes, local ecosystems become more prone to invasion. Invasive species are the second utmost threat to the loss of biodiversity, following habitat loss. The introduction of extra competition to a natural landscape increases pressure on native plants, which usually results in the native species being outcompeted. Given the right set of conditions, invasives can eliminate native species in an area in a matter of years. Some invasive species do not have competition, which makes them an even greater threat. For example, the emerald ash borer (Agrilus plannipennis) has no serious predators in North America (although research is finding that there are native predatory wasps which may be able to control this pest), making it an almost unstoppable force. Invasive species have direct impacts to the economy, with costs from the loss of production from agricultural and forest practices, as well as the management of invasive species. Invasive species can also incur costs in other sectors of the economy, such as recreation and tourism. On paper, the costs relating to production loss and management efforts are not very high; however, when a monetary value is placed on the loss of biodiversity and ecosystem services, and the extinction of species, the costs increase substantially! The costs relating to invasive species are not always direct, and it may take years before one may notice the damage and changes invasive species have produced to the environment, both environmentally and economically. Activity: Split the class into groups and have them develop an invasive alien species (IAS) of their own. The requirements of IAS is that it must compete with and/or destroy a tree species. Have each group draw their IAS, and give as much information about it as possible, for example, its life cycle, the negative effects it poses to the environment, etc. Alien Invaders Fact Sheets Biodiversity 4