Sunday, July 31, 2011
Phenology
Another warm day on the North Shore. Highs in the low 80's with lows in the upper 50's. Cook County is under a "hydrologic outlook". Apparently we should be expecting a storm tomorrow carrying with it 1-2.5 inches of rain. After the massive 4 inch rain event a couple of weeks ago the area currently is at about 115% normal precipitation. Meaning that we have received about 15% more rain that the average year. The blueberries are ripe on the Gunflint! Let the harvest begin...
Thursday, July 28, 2011
Isle Royale
At nearly 50 miles long and 9 miles wide, Isle Royale is the largest of 200 some remote islands that make up of an archipelago situated roughly 20 miles from the Minnesota-Ontario north shore of Lake Superior.
The island itself is a series of SW/NE trending asymmetric linear ridges. The rock on the northwest side of the island steeply drops into the cold waters of Superior while the rock on the south side gently slides into the breadth of the lake. There are two main rock units found on the island.
The Portage Lake volcanics formed during an episode of volcanoes that extruded flood basalts during the Precambrian (about 1.1 billion years ago). The northern two thirds of the island is comprised of various textured basalts. These textures (opitic, porphorytic, pegmatic, etc.) are a result of the environment that the rock crystallized. Copper and secondary minerals like prehnite, greenstone and agate filled the voids that fractures and gas bubbles left.
The southern third of the island is composed of a unit known as the Copper Harbor Conglomerates. Deposited in streams, this sedimentary rock unit looks like a bunch of pebbles and sand compressed and cemented together.
To understand the origin of these two rocks we have to think big. Over a billion years ago Earth was still "figuring itself out". The beginnings of the North American continent had formed. However, this mass was unstable and found itself rifting apart down the middle. Magma from deep within the Earth began to dome upwards as the rifting thinned the surface. This magma found its way to the surface and lava flowed on the surface and in shallow water (think about the volcanoes of Hawaii).
When billions of tons of heavy, dense iron-rich volcanic basalt oozed to the surface the weight depressed the crust. The area around the rift began to warp downward. Soon a syncline (basin) was formed. Water, always opportunistic, found this relatively low basin and began to flow into it carrying sediment from the highland areas around it. As a result conglomerates and other beds of siltstone and sandstone were deposited atop the basalts of the Portage Lake Volcanics waiting for us to explore.
Since then four major episodes of glaciation and closely associated changing water levels have carved out the Lake Superior basin and the landscapes that we see today.
Prehistoric people discovered the island and prized it for it's obvious copper wealth. Over one thousand prehistoric mining pits have been documented on the island. Apart of it's minerals, Isle Royale was also an important source of wild rice, berries and wild game.
Three major mining booms have since occurred on the island. The hard work of "blast and dig" mining never proved economical successful and most operations failed without profit. Many pits and abandoned equipment can still be found throughout the island.
Commercial fishing was also a vibrant part of the island's history. Isle Royale's unpredictable topography and reefs are wrecked many ships on it's notorious shoals. A hand full of lighthouses round the island's perimeter and light it's passages.
Isle Royale is now the stage of the dynamic saga for one of the most hailed predator-prey relationships in the world. For more than 50 years, biologists have been watching the delicate interactions between the grey wolf and moose. Moose probably swam to Isle Royale around the turn of the 20th century. At any given year about 1000 individual moose have inhabited the island feeding on the plentiful vegetation of the the island's wetlands. At one point, moose became too abundant. The island's vegetation wasn't enough for the booming population. A die off ensued. Sometime around 1940 wolves crossed from the mainland on the winter ice. Since then the two species have been tangled in a natural exhibit of capable predators killing the weak and old. Today just under twenty wolves inhabit the island.
Now the least visited National Park, Isle Royale is an amazing place to visit. 80% water, one can sail, fish, hike or paddle it's beautiful landscapes. My only qualm; it should be considered a part of Minnesota not Michigan!
The island itself is a series of SW/NE trending asymmetric linear ridges. The rock on the northwest side of the island steeply drops into the cold waters of Superior while the rock on the south side gently slides into the breadth of the lake. There are two main rock units found on the island.
The Portage Lake volcanics formed during an episode of volcanoes that extruded flood basalts during the Precambrian (about 1.1 billion years ago). The northern two thirds of the island is comprised of various textured basalts. These textures (opitic, porphorytic, pegmatic, etc.) are a result of the environment that the rock crystallized. Copper and secondary minerals like prehnite, greenstone and agate filled the voids that fractures and gas bubbles left.
The southern third of the island is composed of a unit known as the Copper Harbor Conglomerates. Deposited in streams, this sedimentary rock unit looks like a bunch of pebbles and sand compressed and cemented together.
To understand the origin of these two rocks we have to think big. Over a billion years ago Earth was still "figuring itself out". The beginnings of the North American continent had formed. However, this mass was unstable and found itself rifting apart down the middle. Magma from deep within the Earth began to dome upwards as the rifting thinned the surface. This magma found its way to the surface and lava flowed on the surface and in shallow water (think about the volcanoes of Hawaii).
When billions of tons of heavy, dense iron-rich volcanic basalt oozed to the surface the weight depressed the crust. The area around the rift began to warp downward. Soon a syncline (basin) was formed. Water, always opportunistic, found this relatively low basin and began to flow into it carrying sediment from the highland areas around it. As a result conglomerates and other beds of siltstone and sandstone were deposited atop the basalts of the Portage Lake Volcanics waiting for us to explore.
Since then four major episodes of glaciation and closely associated changing water levels have carved out the Lake Superior basin and the landscapes that we see today.
Prehistoric people discovered the island and prized it for it's obvious copper wealth. Over one thousand prehistoric mining pits have been documented on the island. Apart of it's minerals, Isle Royale was also an important source of wild rice, berries and wild game.
Three major mining booms have since occurred on the island. The hard work of "blast and dig" mining never proved economical successful and most operations failed without profit. Many pits and abandoned equipment can still be found throughout the island.
Commercial fishing was also a vibrant part of the island's history. Isle Royale's unpredictable topography and reefs are wrecked many ships on it's notorious shoals. A hand full of lighthouses round the island's perimeter and light it's passages.
Isle Royale is now the stage of the dynamic saga for one of the most hailed predator-prey relationships in the world. For more than 50 years, biologists have been watching the delicate interactions between the grey wolf and moose. Moose probably swam to Isle Royale around the turn of the 20th century. At any given year about 1000 individual moose have inhabited the island feeding on the plentiful vegetation of the the island's wetlands. At one point, moose became too abundant. The island's vegetation wasn't enough for the booming population. A die off ensued. Sometime around 1940 wolves crossed from the mainland on the winter ice. Since then the two species have been tangled in a natural exhibit of capable predators killing the weak and old. Today just under twenty wolves inhabit the island.
Now the least visited National Park, Isle Royale is an amazing place to visit. 80% water, one can sail, fish, hike or paddle it's beautiful landscapes. My only qualm; it should be considered a part of Minnesota not Michigan!
Sunset over Blake Point. The northern most point of Isle Royale.
Flash flood!
One of the best things about living in the woods is the opportunity to experience the subtle but continual changes of nature. Some things, however, aren't very subtle.
I'm lying awake at 2:30 am listening to the rain fall on our metal roof. I'm anxious because in a couple of hours I'm getting up to drive to Grand Portage to catch a boat to Isle Royale to guide a backpacking trip. What started as a calm rain shower soon becomes a down pour. The down pour continues through the remainder of the night and into the morning when at 5:30 I drive down the road. At this point the ditches are completely full.
Driving up Highway 61 to Grand Portage that morning was like winter driving in July. As the truck was hydroplaning at every low point in the road I couldn't help but think about the homestead. I couldn't go back. I was committed to catching that boat and guiding a five day backpacking trip. Rolling over 3-5 foot waves later that morning with lightening shattering the distant Canadian sky I knew that the situation at home wasn't good. However, on the remote island and without any form of communication for five days I had to trust that Amy had the situation under control.
Needless to say the rain poured down relentlessly until mid morning. Over four inches of rain fell. Our ditch was scoured down to bedrock. All of the rock in it was transported by the torrent down to the culvert. The pipe soon clogged up and with no place to go the water rushed over the driveway and road. Within moments the road was washed away!
Amy headed back home after dropping me off to catch the boat. Driving up the washed-out County road leading home she knew right away that things were bad. Debris had covered the base of the driveway. The culvert was no where to be found. She was able to locate the outlet of the culvert, paced the line back up to where she thought the inlet would be and started to dig. As long as the culvert was buried water would continue to run over the road and exacerbate the damage! After a couple of hours of digging she finally found the inlet and was able to get the runoff to drain into the culvert. She spent the next two days digging and filling in the freshly incised channels in an attempt to level out the road surface to make it passable.
Five days later I got home to find a place much different than I had left. We have spent the last few days digging and and "patching" the base of the road of. Right now we are just happy that we can get to our new home and thinking of ways to deal with the next time it decides to dump 4 inches of rain on us! Once again we've found that it all comes down to water and how it interacts with the landscape; particularly at it's most violent moments...
I'm lying awake at 2:30 am listening to the rain fall on our metal roof. I'm anxious because in a couple of hours I'm getting up to drive to Grand Portage to catch a boat to Isle Royale to guide a backpacking trip. What started as a calm rain shower soon becomes a down pour. The down pour continues through the remainder of the night and into the morning when at 5:30 I drive down the road. At this point the ditches are completely full.
Driving up Highway 61 to Grand Portage that morning was like winter driving in July. As the truck was hydroplaning at every low point in the road I couldn't help but think about the homestead. I couldn't go back. I was committed to catching that boat and guiding a five day backpacking trip. Rolling over 3-5 foot waves later that morning with lightening shattering the distant Canadian sky I knew that the situation at home wasn't good. However, on the remote island and without any form of communication for five days I had to trust that Amy had the situation under control.
Amy headed back home after dropping me off to catch the boat. Driving up the washed-out County road leading home she knew right away that things were bad. Debris had covered the base of the driveway. The culvert was no where to be found. She was able to locate the outlet of the culvert, paced the line back up to where she thought the inlet would be and started to dig. As long as the culvert was buried water would continue to run over the road and exacerbate the damage! After a couple of hours of digging she finally found the inlet and was able to get the runoff to drain into the culvert. She spent the next two days digging and filling in the freshly incised channels in an attempt to level out the road surface to make it passable.
Five days later I got home to find a place much different than I had left. We have spent the last few days digging and and "patching" the base of the road of. Right now we are just happy that we can get to our new home and thinking of ways to deal with the next time it decides to dump 4 inches of rain on us! Once again we've found that it all comes down to water and how it interacts with the landscape; particularly at it's most violent moments...
Wednesday, July 27, 2011
Listening to the cicada
The temperature and humidity are dismally closely aligned in the 80's. Fog blankets Lake Superior day and night. Every once and a while a misty cloud bank is forced up the driveway by a cool blast of lake air. The dog is panting on the cement. We wake in the morning to the sound of cicadas chirping.
We are coming up on a month of living on the property. Now officially out of our rental in town, every single one of our belongings are here in one place once again. Slowly, we are steadily building shelves and storage to make sure that everything finds a home. Amy has most of the art collection on the walls. In short life is simple and comfortable.
The chores have just begun. Beyond hauling the daily water I have begun putting up the upcoming winter's firewood supply. It's kind of ironic to be thinking about splitting firewood for the winter when the heat index is over one hundred degrees. That is, however, exactly the direction where my mind and efforts have begun to go! Last week one of our local loggers delivered three cords of birch. The logs were delivered in 16' lengths. It is now my task to buck the logs into 16" lengths, split it in half and stack to dry. This birch will be supplemented with some poplar cut around the property.
As usual, there's plenty of work to be done. However, for the time being I just going to sit at my desk, write, and listen to the cicada...
We are coming up on a month of living on the property. Now officially out of our rental in town, every single one of our belongings are here in one place once again. Slowly, we are steadily building shelves and storage to make sure that everything finds a home. Amy has most of the art collection on the walls. In short life is simple and comfortable.
The chores have just begun. Beyond hauling the daily water I have begun putting up the upcoming winter's firewood supply. It's kind of ironic to be thinking about splitting firewood for the winter when the heat index is over one hundred degrees. That is, however, exactly the direction where my mind and efforts have begun to go! Last week one of our local loggers delivered three cords of birch. The logs were delivered in 16' lengths. It is now my task to buck the logs into 16" lengths, split it in half and stack to dry. This birch will be supplemented with some poplar cut around the property.
As usual, there's plenty of work to be done. However, for the time being I just going to sit at my desk, write, and listen to the cicada...
Sunday, July 17, 2011
Phenology
Warm, humid. It's not very often that the North Shore is issued an "excessive heat warning" but with highs in the mid to upper 80's and a humidity level of equal value we find ourselves laying around in the shade-too hot to tackle the projects that we had hoped to accomplish. This may not sound "hot" to folks further south but keep in mind that the average annual temperature around here is 39. Our tomatoes, however, are loving the heat. This morning we noticed our first piece of fruit!
Tuesday, July 12, 2011
Phenology
Warm, sunny. Highs in the low 70's and lows in the mid 50's. Over three inches of rain fell in the last couple of weeks. Despite this climate data ranks precipitation values about 10% below average. Dew berries, strawberries and heal-all are in bloom. Summer on the North Shore is in full swing!
Sunday, July 3, 2011
Shoe Lake
Shoe Lake is nestled into the rolling white pine-clad hills of the "Greenwood country" in eastern Cook County. It's shoreline is rimmed with black spruce, northern white cedar, labrador, sphagnum moss and the occasional tamarack. Common to many lakes in the higher elevations of the Duluth Complex, Shoe Lake's outlet is bedrock controlled. The means that the lake's water level is trapped behind bedrock. The lake is shallow (just shy of 20 feet at it's deepest point) yet it supports a decent population of brook trout and splake (hybrid of brook and lake trout).
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