TOPIC 5 – THE BOREAL FOREST

 Boreal Forests are also known as TAIGA forests  What portion of forests are BOREAL?  Boreal forests are CIRCUMPOLAR, meaning they circle the earth, spanning the top of Northern Europe, North America, and Asia (Called the “great green scarf” the Earth)  82 % of all Canadian Forests are boreal (Largest Canadian Biome)  100 % of NL forests are boreal

 Coldest biome on Earth other than the tundra  Latitude is degrees north of equator  Long, cold winters lasting 5-6 months of the year  Short, warm summers  Precipitation is generally snow  Temperatures:  –50 0 C to 30 0 C throughout the year  average is less than 10 0 C for eight or more months of the year

 The Boreal forest is the SLOWEST GROWING FOREST on EARTH  WHY?  Shoot/root growth does not occur until temperature is high enough  Short Growing Season – 130 days  Low decomposition rate due to cold temperatures, so nutrient levels in soil are low  Extreme weather is common, killing buds and reducing growth  Cold snaps during growth season can reduce growth for the next season

 SOIL is THIN(SHALLOW).  Soils is ACIDIC  Due to decomposing needles  Soil has LOW DRAINAGE  Evergreens provide permanent shade, so soil is often waterlogged as a result.  Soils is NUTRIENT-POOR  Decomposers are slower in cold, acidic soil  Waxy coating of evergreens makes for a slower decomposition rate

 On a species level, it the LEAST BIODIVERSE of all forest types  Sometimes called the “spruce-moose” forest!  Why?  With colder temperatures, and slower decomposition rates, ENERGY AVAILABILITY IS LOW  Recall the FLORA means “plants” and FAUNA means “animals”

 Boreal forests are mostly CONIFEROUS, with a smaller portion of DECIDUOUS TREES  Most common trees are coniferous softwoods BLACK SPRUCE and BALSAM FIR.  Other softwoods include Eastern larch and pine.  The smaller portion deciduous hardwoods include white birch and trembling aspen.

 Used in NL for pulp and lumber  Most abundant tree on the island, 2 nd most abundant in Labrador  At maturity, about m in height meters in height and cm in diameter  Can reach ages of yrs old  Favourite snack of MOOSE  Most common naturally disturbance is INSECT DAMAGE  Needles are flat (will not roll in fingers) and grow horizontally on twig  Memory Tool: Flat is Fir

 Provincial tree of NL  Used in NL for pulpwood and for Christmas trees  Most abundant tree in Labrador, 2 nd most common on island  At maturity, about 9-12 m in height and cm in diameter  Can reach age of 200 years  Most common disturbance is FIRE, cones are adapted to survive fire  Needles are four-sided, will roll in fingers and are spirally arranged  The other common spruce in NL is white spruce.

 Makes good posts and poles.  Many locals incorrectly call this tree a juniper in NL  It is an unusual conifer because it drops its needles in winter (deciduous conifer).

 Most common birch in NL and most important HARDWOOD in NL  Also called the paper birch or canoe birch  Used for fuel wood and in value-added wood products  scattered over the island but common in valleys on west coast of island  Other less common birch is YELLOW BIRCH

 What types of fauna live in our forests?  Moose  Black Bear  Woodland Caribou  Canadian Lynx  Snowshoe Hare  Red Squirrel  Little Brown Bat  Mink  Coyote  Beaver  Newfoundland Marten  Red Fox  Masked Shrew  Voles  Rock Ptarmigan

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TOPIC 6 – SURVIVING THE HARSH ENVIRONMENT of a BOREAL FOREST

 Coniferous leaves are modified to prevent dessication, which means “drying out”  They are modified into needles or scales that:  decrease surface area  reduce water loss by transpiration (evaporation from leaves)

 Conifers have downward sloping of boughs, allowing trees to shed a heavy snow load.

 At low temperatures between 0 to -40 degrees Celsius, other trees might freeze to death.  In conifers, liquids in the tree remain liquid, a process known as super cooling.  Some conifers that can survive below -40 degrees Celsius include white and black spruce, and tamarack

 Due to the ALBEDO EFFECT, darker objects absorb more heat energy as compared to lighter–hued objects.  The dark green of conifer needles helps the trees absorb the maximum heat from the sun and begin photosynthesis as early as possible

 Example:Black Spruce  It produces two types of seed cones, CLOSED and OPEN CONES.  Open seed cones drop each year and sprout in any area where there is enough light to grow.  Closed cones cannot release their seeds unless heated to a high temperature by fire. The heat of the fire melts the resin that acts like glue to keep the seed cone closed