Sunday 24 April 2016

The Sea Lion, Mosses and Lichens at Sleeping Giant

While visiting Alex in Thunder Bay we decided to make a day trip to the Sleeping Giant, the Sibley peninsula jutting into Lake Superior which you see from town.
The Sleeping Giant as seen from Hillcrest Park
It was a bright and sunny day with spring run-off at full tilt.
Spring run-off headed for Lake Superior

We decided on a relatively unambitious hike to the Sea Lion, a rock arch jutting into Lake Superior.  It is always so much fun to take a walk in the woods with Alex since she can animate what we are seeing with so much information.
 The Sea Lion
Thea, Alex's dog, loved the snow left in the shade of the path through the woods.
Thea, the snow dog!

As we scrambled up the rocky path to the higher elevation we came across a patch of reindeer lichen right next to an outcropping of cauliflower lichen. They are both silver and strikingly similar. To my untrained eye I would have assumed they were the same species. However, they are two different species of the same genus, Cladina. This nitrogen-rich lichen is the preferred food of the woodland caribou.
Reindeer lichen
Cauliflower lichen

In addition to lichen there were lots of mosses. Alex explained that while they weren't restricted to the boreal forest the role they had to play in the nitrogen deficient, mainly coniferous woods was important to the overall health of the forest. Coniferous forests, without the benefit of the rich leaf litter found on the floor of a mixed or deciduous forest, have few sources of nitrogen. But, as limiting to nitrogen, is the cold climate and short growing season of the boreal forest. This restricts the ability of trees to photosynthesize which is one of the main mechanisms by which they accumulate nitrogen.  Nitrogen is also scarce because of the youth of the recently (geologically) glaciated soil of the northern forest.

Unlike trees, mosses don't require photosynthesis to fix nitrogen from the air. Nitrogen is the most abundant gas in the earth's atmosphere. Mosses have the ability to store nitrogen in their tissues. This stored nitrogen becomes a source for trees and plants in times of scarcity. Feather mosses are very common and the only mosses to fix nitrogen. There are many types of feather mosses. Below are three of the most common examples.
Schreiber's Moss
Stair-step Moss
Plume Moss

We had a picnic lunch overlooking the Sea Lion. There was a beautiful moss, a type of Dicranum moss, which caught the sunlight at ground level. From above it was barely noticeable but the direction and height of the sun when we were seated made it appear to be on fire. It came as no surprise that it is called Fire Moss. These mosses can colonize after fire and on exposed rocks with little soil.
Fire Moss





Christopher noticed an amazing spruce tree. From a distance it just seemed to be growing on the edge of the cliff. But closer examination revealed it's roots cantilevered over the water below after having been exposed by erosion on the cliffside.
Spruce overlooking the pristine Lake Superior


Upon closer inspection the roots on cliffside are exposed 

A closer view of the spruce's roots with the beautifully clear green water below


Thinking about shared gene pools made me notice some other distinct similarities when we got back to Alex's place and I was able to get a closer look at our photos.
Alex and Christopher

Me and Alex

This blog is dedicated and completely informed by Alex who has taught me so much; most importantly to see when I look - and has also saved me hours of research!



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