Monday, November 9, 2020

Winter: The Iconic "Georgian Bay Tree"

Picture a Georgian Bay tree.

Did you picture a white pine? I imagine you did! The white pine is the classic Georgian Bay tree. You know the one; its windswept branches arc across the surfaces of paintings, pillows, mugs, and t-shirts in nearly any gift shop or d├ęcor store in the Biosphere. In fact, the Georgian Bay Biosphere’s own logo features a white pine!

So why is this tree so closely connected to Georgian Bay? Let's explore some of the reasons why the white pine is such a special tree for so many people. Maybe it’s a special tree for you, too!

An iconic "windswept white pine" grows on the shores of Georgian Bay.
Credit: Kayla Martin


A
Special Look

White pines are very common in and around the Georgian Bay Biosphere because they can grow in the thin soils that cover all the bedrock in the landscape (the Canadian Shield!). Sometimes you will even see a white pine growing in a tiny pocket of soil in a crack among the rocks. Not all tree species can tolerate the shallow soils and strong winds along Georgian Bay, but the white pine can!

Shallow soils and windy weather? White pines don't mind!
 Credit: Kayla Martin

White pines have bundles of long green needles along their branches. One way to identify a white pine is to count the number of needles in each bundle. There should be 5 needles per bundle, and since there are 5 letters in the word “white” you can just remember the number 5 and it will help you identify this tree. White pines are coniferous trees, meaning that the tree’s “leaves” are actually long, narrow needles, and the tree keeps most of these needles year-round. This is different from a deciduous tree (like a maple or oak), which has flat leaves that drop to the ground in fall and regrow in spring. White pines have tall, straight trunks… but sometimes the trunks grow into a curved shape. This happens sometimes out in open areas on Georgian Bay, where strong west winds push against white pines constantly for years as the trees grow. This is how we ended up with the classic “windswept pine” icon for Georgian Bay!

From left: needle bundle (5 needles), branch tip, and pine cone, all from a white pine. Credit: Kayla Martin

White pines were also a favourite subject for the Group of Seven, a group of Canadian artists well-known for their landscape paintings.

Does this look familiar? It's "White Pine" by Group of Seven painter A.J. Casson, from around 1957. 

     

   A Special History

For thousands of years, Indigenous people were also sharing their knowledge about white pines. The resin (the sticky goo that sometimes drips out from the tree) was traditionally used by Indigenous People to cover wounds to help prevent infection. The sticky resin could sometimes be used to seal the seams on waterproof wiigwaas jiimaanan (birchbark canoes).


    A Special Building Material

White pines also captured the attention of European settlers who came to what is now Ontario. In the 1800s, many people were logging (cutting down) white pines. The tall, straight trunks of the white pines were perfect for building tall masts for big sailing ships that were used to send materials between North America and Europe. Later on, in the mid-to-late 1800s, people started to use white pine timber for building homes and buildings.

Logging white pine in Foley Township, around the year 1880.
Credit D.F. Macdonald and Parry Sound Public Library.

People chose to cut down the oldest, largest trees. White pines can be very big and very old: they can grow over 30 m tall, almost 4 m in diameter (thickness of the trunk), and can be hundreds of years old! There were some old, tall white pines all throughout the Biosphere, but unfortunately they were cut down. 

These days people try to be more careful about logging. We avoid cutting down too many big, old trees all in one place. In many years the Biosphere will hopefully have lots more big, old white pines!

 

    A Special Tree for Wildlife

The Biosphere animals may not be able to decorate their burrows, dens, and nests with white pine-themed pillows and artwork, but the animals love white pine just as much as people do!

First, many animals use white pines for shelter. For example, black bears send their cubs to the “white pine daycare”. While the mother bear goes out to search for food, she might leave her cubs up in the safety of a big white pine. The sturdy branches support the weight of the cubs and the strong, rough bark makes it easier to climb up the tree. White pines also provide good nest sites for birds such as bald eagles, osprey, and Cooper’s hawks. Pileated woodpeckers excavate holes in white pines when feeding or creating a nest cavity. Once a pileated woodpecker is done with a nest cavity, other animals (such as chickadees and flying squirrels) might take up residence in the cavity.

Peek-a-boo, peeper! A spring peeper hides in the bark of a white pine.
Credit: Kayla Martin

Can you find the bird?
This Brown Creeper goes up and down the trunk of a white pine in search of tasty insects!
Credit: Kayla Martin

Next, white pine is a popular item on the menu for many animals in the Biosphere. Porcupines gnaw on the bark of white pines. Snowshoe hares and white-tailed deer like to eat the new growth (soft needles). The seeds are also eaten by small mammals such as red squirrels and mice and birds such as pine grosbeaks. These animals have to work hard to break open the pine cones, exposing the little seeds inside. 

The seeds (left) of a white pine are protected in a pine cone.
Credit: Nancy Castillo


But how can white pines spread their seeds if animals keep eating the seeds? Well, many trees including white pines have a strategy for that! It’s called a mast year. In the case of trees, mast means all the seeds produced by a tree, whether these seeds are in the form of acorns or in pine cones. White pines, for example, produce lower amounts of seeds (in pine cones) most years (non-mast years). They save up energy by not producing a lot of seeds, but unfortunately for the trees many of their seeds during non-mast years will be eaten. Every 7-10 years, a white pine has stored enough energy that it can produce a LOT of seeds. When this happens, it’s called a mast year. Here’s the trick: the white pine produces SO MANY seeds that there are simply too many for animals to eat them all. This means some seeds will remain and hopefully grow to become big white pines.