Taking Prescribed Fires off the “back burner” at River Bend Nature Center

Where there’s smoke, there’s fire. Or at least, that’s the idea.

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2017 shapes up to be a successful year for prescribed burns at River Bend Nature Center. This grassland/forest mix behind the interpretive center was one of the first locations burned this last Saturday.
Photo credit: Stephanie Rathsack

In a world where fire is often seen as a danger to life and property, it’s easy to forget that fire is actually a natural part of a healthy ecosystem, and that in some cases, it is necessary for the survival of native plants and animals. This leads many to ask how this could be possible, when the landscape after a fire looks as far from lively as you can get: shriveled and blackened grass, charred stumps, and an ashy sky. It doesn’t exactly look appealing. It takes a closer examination to discover the real benefit of allowing fire to move through our prairies and forests.

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Immediately following a fire, the ground is left dry and charred. But it won’t stay like this for long.
Photo credit: Stephanie Rathsack

Underneath the burned ground, an incredible change is taking place—nutrients that were once trapped inside plants on the surface are now recycled back into the soil. In this way, nutrients are not locked away, but become available for new plants to utilize. This becomes especially true in prairie ecosystems, where grasses are prevalent, dying back every winter and holding nutrients in their dead stalks above the soil line. Perhaps even more amazing after a fire, some seeds buried in the ground begin to stir and show signs of life after what could have been years of dormancy.

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Large, healthy trees remain undamaged when a prescribed burn moves past. The removal of competition around it will even help it to thrive.
Photo credit: Stephanie Rathsack

In some cases, seeds are even coated with flammable oils to encourage hotter fires. These fire-dependent species require high heat for germination to be triggered, when otherwise it would not occur at all. Plants developed such traits in order to exploit the lack of competition following a fire. With other species removed, new plants that germinate quickly afterwards do not have to fight for sunlight or water with any nearby neighbors. A famous example of this is the Lodgepole pine, whose cones are sealed with a special resin that melts away in the high heat of fire and releases the seeds. There are many ways that plants have evolved to make use of fire—species may rely on fire, smoke, or a combination of both in order to prosper.

1Source: http://www.austintexas.gov/rxfire

This knowledge flies in the face of years of misunderstanding—that ecosystems are always moving towards a state of equilibrium, where nature and all of its components end in harmony. The reality is far different—nature not only utilizes, but requires frequent “disturbances”, whether this be in the form of fire, flood, or landslide. And so rather than thinking of a forest or prairie as a linear progression towards an endpoint, it is better to think of them as a cycle, where plants grow, die, are recycled back into the system, and begin again. This mindset is known as ecological succession—old growth forests will inevitably become disturbed sites where new, younger individuals will emerge and age. In the end this results in a healthier ecosystem, which is easy to see when comparing pre-settlement forests to modern forests. Before human intervention, forests often had fewer but larger and healthier trees. Now, forests have far more trees, but they are overcrowded, smaller, and generally less healthy.

 

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Source: https://www.cs.hmc.edu/~sweil/bio52/3/fireeco.html

 

Ironically, it is the modern, “protected” forests that pose the greatest threat, both to humans and wildlife. When fire is prevented, forests mature beyond the point of being prosperous—food/water amounts and space lessen, and wildlife suffers as a result. Additionally, dead plant matter builds up, which creates more fuel. Eventually, the amount of fuel present in the forest may allow for a larger, hotter, and more dangerous fire to occur.

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Prescribed burns prevent fuel from building up in a forest or prairie ecosystem–the result is more frequent but smaller fires that are less likely to get out of control.
Photo credit: Stephanie Rathsack

And so it all comes down to word choice. Many of us may remember the famous Smoky the Bear phrase “only YOU can prevent forest fires”. This was a great and catchy slogan for a world where fire could cost hundreds of millions of dollars in damages, both to buildings and natural areas. But as we began to learn more about this land we were trying to “protect” by putting out every fire we could find, scientists began to realize that our “help” was actually causing harm. And so rather than advertising a negative image on “forest fires”, Smoky now reminds us to stop “wild fires” instead—that is, fires that are unintentional or out of control in a region where lives and property could be lost. This change of heart helped reduce the misconception that all fire is bad—and that any forest or prairie fire is a villain in an ecological sense.

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Nutrients are recycled back into the soil when dead vegetation is allowed to burn. Even greener patches along the river are able to be burned, as Emily Greger, Resource Manager, helps it along with a torch.
Photo credit: Stephanie Rathsack

But what does this have to do with River Bend? There is one more benefit from fire that River Bend will be utilizing very soon, and that is to use fire as a tool to remove invasive species. While hours of work every year go into removing invasive species from the property, pulling, cutting, and treating, it is not the most effective way to prevent the spread of non-natives. Fire works much faster and far more thoroughly than any “by hand” methods of removal, making it the most effective tool at our disposal. And while historically, prescribed fires have been used sporadically and on small sections of land, we plan to increase the area covered, and also begin burning on a regular rotation. One burn is not enough to bring a habitat back to “pristine” condition—it takes several burns in addition to other treatments, and the entire process might go on for years. However, in the end, after a lot of planning and work, the goal is that eventually we will be left with forests and prairies that resemble pre-settlement—healthy ecosystems filled with a large variety of native plants and animals.

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Visitors can expect to see signs of burning through the end of April, and sites on the list of potential burns are the rain garden, the large prairie by the Interpretive Center, ditches along Rustad Road, the gravel pit, and the prairie on Teepee Tonka.

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Tall grasses burn readily–moving very quickly across a prairie landscape. A “back burn” will prevent fire from spreading to undesired locations.
Photo credit: Stephanie Rathsack

Dates and times of burns are all weather dependent, and all burning will cease before May in order to protect ground nesting birds. Helping us with this process is the Faribault Fire Department, who has been donating their time and equipment for decades.

4357Fire creeps up to the banks of the Straight River which acts as a perfect fire break.
Photo credit: Stephanie Rathsack

And while we cannot ask for volunteers from the public to help with burns, there are several things you can do to help make this process as simple and safe as possible:

Take note of any and all signs posted notifying the public about potential burns. When burning, there will be a large sign posted by the park entrance asking that people stay away from the areas that are being burned, both for their safety as well as the safety of the staff—distractions can lead to dangerous situations. Another way that you can help is by attending several events that River Bend has coming up—the first is an OWLS (Older Wiser Livelier Seniors) presentation given by River Bend’s Resource Manager Emily Greger. The presentation will focus on invasive species, going beyond buckthorn and touching on lesser known species and methods for controlling them. Additionally, River Bend hosts Restoration work days where members of the public can come out and assist with a variety of restoration projects, including removal of invasive species. For more information on these programs and other opportunities please see our website: http://www.rbnc.org/

OWLS – https://riverbend.z2systems.com/np/clients/riverbend/event.jsp?event=1631&

Restoration Work Day – https://riverbend.z2systems.com/np/clients/riverbend/event.jsp?event=1641

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Fire will drastically change the appearance of a landscape, but in just a few weeks, this same location picture in both photos will be green with new and healthier growth.
Photo credit: Stephanie Rathsack

A Day at the River Bend Sugar Bush – part II

We last left off with sliding down snowy and icy paths to collect buckets of maple sap. It’s been a few weeks now, and the River Bend sugar bush is working at full steam. With a total of about fifty trees tapped, we are continuing to collect sap every day with the help of staff and volunteers. On March 6th we collected a record amount of sap for the season—145 gallons! (This was produced by the trees in less than twenty-four hours)

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Photo Credit: Stephanie Rathsack
In a record total for this year’s sap season, we collected 145 gallons of sap in less than twenty-four hours.

With that much sap alone we’d be able to produce about three and a half gallons of maple syrup. Our recent collection runs have been less icy, but far more muddy, making the treks through the sugar bush tricky at worst, and extremely messy at best.  But shoes full of muck is a fair price to pay for the increased sap production that occurs with days in the 40s and 50s.

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Photo Credit: Stephanie Rathsack
With warm weather, sap bags (which hold about 2 gallons) can fill up quick!

And though increasingly warmer temperatures hark the end of the sap season, we expect to continue being able to collect through the end of the week, and into the following week as well. Meanwhile, the maple sap that has been collected up to this point is getting boiled down to begin the transformation from sap to syrup. This process requires high heat over a long period of time, for which we use a maple sap evaporator, which looks a bit like a giant wood burning stove. The sap is fed into the tank via gravity, and heat from the fire evaporates the water out, slowly decreasing the liquid in the sap and increasing the concentration of sugar.

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Photo Credit: Stephanie Rathsack
We let gravity do most of the work, as the sap starts in a bin held high off the ground before traveling down into the boiling chambers.

Maple sap generally has a 2-3 percent concentration of sugar, and this must be increased to about 68 percent found in maple syrup. This immense reduction in water requires large amounts of sap to be boiled for several days before it is ready to be bottled as syrup. Again with the help of volunteers and staff, the evaporator gets up and running early in the morning, and requires constant supervision throughout the day in order to continue feeding the fire, monitoring sap levels, and preventing scorching.  Even after several days on the evaporator, the syrup still is not completely finished—it requires a period of time on a stove top where the heat can be more fine-tuned and the syrup can move through its final stages of processing.

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Photo Credit: Stephanie Rathsack
Sap is “finished” over a stovetop where temperatures and consistencies can be monitored more closely.

As the sap reaches higher and higher sugar concentrations, it must be watched closely until finally after filtering one last time, bottling can begin. For long-term storage of maple syrup, specialized jars are purchased in a variety of sizes. River Bend bottles their syrup in large gallon jars down to tiny half-pint jars and everything in between. These jars of “liquid gold” will make appearances in a variety of River Bend programs and activities.

 

Want to learn more about maple sap production/taste a sample of this year’s bounty? River Bend is offering a variety of opportunities for the public to get involved in the fun of maple syruping:

 

Maple Syrup Open House– Celebrate syrup season at River Bend Nature Center! On March 18th, 2017 from 10:00AM to NOON there will be a variety of fun and FREE activities to participate in. Learn about the maple syruping process with trivia and taste tests and visit the sugar bush to collect sap, and see the evaporator in full swing.

Maple Syrup Fun Run- scheduled for Saturday, May 6th, 2017. Our races include a 50K, 25K, 10K and 5K trail runs (all jumbo clock timed) and a one-mile fun walk on an accessible paved trail (untimed). Race entry fee includes entry to our Pancake Brunch after the Fun Run, and a race shirt.

Maple Syrup Pancake Brunch– Come out to River Bend on Saturday, May 6th for delicious pancakes topped with River Bend’s own real maple syrup. Our pancakes will be cooked by the expert staff from Bernie’s Grill! We’ll also have sausages, coffee, and juice to accompany our pancakes.

 

A Day at the River Bend Sugar Bush – Part I

With unseasonably warm weather ahead of us for the next few weeks, the staff and volunteers at River Bend Nature Center are preparing for one of the most exciting times of the year—maple syrup season!

As temperatures rise above freezing during the day, but drop below freezing at night, some incredible unseen changes take place under the bark of our forest’s trees. To understand this change takes a bit of knowledge about a tree’s inner workings as well as some basic knowledge of physics. Trees are composed of several layers beneath their bark—these layers include the xylem (sapwood) and the phloem. The phloem transports nutrients down the tree, while the xylem transports nutrients up. When temperatures rise above freezing, pressure builds up inside the trunk, forcing sap out of any wounds or tapping holes (with spiles as shown below). Alternatively, at night when the temperatures fall, the pressure drops and creates suction, drawing water into the tree through the roots. This suction replenishes the sap in the tree and allows it to flow again during the next bout of warm temperatures.

 

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Source: http://www.rmgmaple.com/ZenCart/index.php?main_page=page_3

 

What is a sugar bush?

A sugar bush is a portion of forest that is utilized for the production of maple syrup. It is characterized by a predominance of maple trees. Other species may be present, but the majority of the canopy consists of a combination of sugar, red, black, and other maple varieties. The trees tend to be older, and the same trees may have been tapped for years. During the syrup season, there is usually a layer of snow on the ground, and light snows may still fall (referred to as sugar snows) during the season. Sap production will taper off as temperatures continue to rise, and the sap is no longer collected when the buds begin to burst. After the syrup season is over, a flush of wildflowers often appears between the trunks of the large trees, taking advantage of the sunlight coming through the empty canopy. In the full green of summer, the sugar bush will be cool and shady, followed by a colorful display of autumn leaves.

River Bend’s sugar bush can be found primarily along the south branch of the Owl trail, and very soon sap collection will be going full steam.

 

 

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Source: Stephanie Rathsack

Today at the sugar bush, the season is just getting started. With a cleaning and inventory of all the necessary supplies, we set out into the woods to visit a few of the larger trees. After sliding precariously down icy paths and heading into the cooler cover of the trees, we reached the River Bend Sugar Bush. And down, close to the river, a few tall black maples stand with distinguishable scars on their massive trunks. These trees have been tapped by River Bend staff and volunteers for years and are a reliable source of sap almost every season. The scars from past years where the holes had been drilled are faintly visible in the bark of the trees. They look a little like tree belly buttons. These old wounds need to be avoided when putting in a new spile, because any scar tissue might have redirected the flow of sap. We measure up and over from the most recent scar before drilling into the tree. The shavings spiral out as we drill deeper, and some look and feel a bit damp—a sure sign of sap beginning to flow!

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Source: Stephanie Rathsack

 

With the addition of a spile and a blue sap bag, the tree is ready for the syrup season.

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Source: Stephanie Rathsack

 

 

This process will be repeated almost eighty times, and we’ll find ourselves visiting the sugar bush every day, stomping through the snow to visit each tree to collect the sap, with a bucket in each hand, continuing a tradition that’s been going on for hundreds of years.

 

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Source: Collections Online                                                   Source: Stephanie Rathsack
Minnesota Historical Society

 

Want to learn more about maple syrup, its history, and the transformation from sap to syrup? River Bend will be offering several programs now through the beginning of April, many with a chance to taste some real syrup, or to tap a tree yourself!

Maple syrup workshops will be offered March 8th and March 11th, the maple syrup open house is planned for April 1st, and the Maple Syrup Fun Run is scheduled for May 6th.

Check our website and Facebook for updates on dates and times. Maple sap is temperature-dependent, so all events are subject to change.

“Hopping”Into Astronomy

Winter is in full-swing this week, with fresh snowfalls (not to mention temperature falls). And though this snowy wonderland brings a flurry of activity during the daytime, with school groups coming in almost every day, I’d like to instead dedicate this post to the less-frequently seen beauty of River Bend—that is, what we can only see after dusk. And even though we’ve passed the Winter Solstice, the sun is still setting relatively early, around 5:00 pm, which is good news for those of us who look forward each evening to having the opportunity to be astronomers. I find my own eyes wandering skyward as well, as the light starts to vanish at the end of the day, because no matter how many times I see it, I never get tired of a sky full of stars. But to the amateur astronomer, learning where to start can be a daunting task. With countless telescopes on the market, weighty textbooks filled with complicated diagrams and star charts, not to mention the sheer number of celestial objects to be viewed, it’s enough to make anyone want to quit before they’ve even started. This blog post is meant to serve as a beginner’s guide to astronomy. Whether you’ve taken a few courses in school, or whether you’re just starting to wonder about the night sky, this guide will be a simple tool to take away some of the complications and confusion of amateur astronomy.

The first step to learning about the stars is to not buy a telescope. This is so important and so misunderstood, that it’s worth saying again: do not begin your interest in astronomy with buying a telescope. This is perhaps the fastest way to kill the hobby, as telescopes can be expensive, and are not simple tools to use, even with experience. Even the ones advertised for beginners which promise easy-use, can’t be used for much more than to look at the moon. If you still want to be able to have a “close up” of celestial objects, instead purchase or borrow a pair of binoculars, which are far less expensive, and far easier to use. Truly though, the only tool you need to study and enjoy the night sky are your eyes and a willingness to observe. Couple this with a little bit of study, and you’re well on your way to opening up the entire cosmos. But for the purpose of this blog, we’ll start small, or rather, we’ll start close.

When you look up into the night sky, what you are viewing is a portion of our home galaxy, the Milky Way. On average, without the aid of a telescope or binoculars, you may see up to 2000 stars, although the galaxy is believed to have over 100 billion stars. We are limited on what we can see because of several reasons: Many stars are on the other side of the Earth, some stars are too dim or too far away to be visible, and some may be blocked from sight by other planets or other stars. In fact, some of the difficulty lies in the fact that Earth is positioned within the Milky Way galaxy. If we were outside it, we could view the entirety of the galaxy and all of its stars, but being within it means that we can only ever see portions of it at a time. For those same reasons, the stars that we see with the unaided eye, are only stars within the Milky Way, and they are generally the closest ones as well.

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Photo credit: google images

For the amateur astronomer however, 2000 stars is a great place to start—It’s where our ancestors began and all civilizations before us began as well. These are the stars that make up constellations, and are the easiest and most fun to explore.

In the Northern Hemisphere, the easiest constellations to spot are known as “circumpolar constellations”. These groupings of stars are situated above Earth’s northern axis, and therefore can be seen in the night sky year round, unlike other constellations which appear to rise above and set below the horizon.  Probably the most famous of the circumpolar constellations is the constellation known as Ursa Major, the Big Bear—which includes the Big Dipper.

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Above: throughout the year, the Big Dipper is always visible, but just appears to move in a circle.
Photo credit: google images

The Big Dipper is also the most famous example of an exercise known as “star hopping”. In star hopping, the viewer takes stars that he or she is familiar with, and uses them to find stars and constellations they are less familiar with. In this way, your knowledge can easily be expanded across the sky! To locate the Big Dipper, start by looking North. If you are not sure which direction North is, start by picking the darkest section of sky. At the time of this post, the Big Dipper is located relatively low near the horizon, so begin your search there, turning in a slow circle and search for a bright grouping of stars. In the winter, the Big Dipper appears to be standing on the end of its handle, with the bucket pointing straight up. To begin star hopping, once you find the Big Dipper, locate the two end stars of the bucket (known as pointer stars) and follow them towards the next brightest star, as shown in the above image. In this way, you have successfully “hopped” to the North Star, Polaris, and also the constellation Ursa Minor (Little Dipper).  Polaris is the last star in the “handle” of the Little Dipper. After acquainting yourself with which direction is North, this will allow you to locate even more constellations.

Another easy circumpolar constellation to spot is Cassiopeia the Queen. To star hop to this constellation, continue following the path of the pointer stars from the Big Dipper, past Polaris the North Star, and the next brightest star along that curve is Cih, the central star in the w-shaped constellation Cassiopeia.

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Above: Starting with the Big Dipper, follow the pointer stars up to Polaris, and finally up to the W of Cassiopeia.
Photo credit: Stellarium

In addition to the Circumpolar constellations, there are easy to spot groupings of stars that are most prominent in certain seasons. In the Winter, this includes the constellations Orion, Canis Major, Canis Minor, Taurus, and Gemini. The easiest of these constellations to find, is the constellation of Orion, the hunter. It is also from this constellation that you may star hop to several others listed previously. To find Orion in the night sky, look to the Southeast, midway between the horizon and directly overhead. The most prominent section of Orion is the three stars that make up his belt. These stars are grouped closely together in a straight line, while the remainder of the constellation forms something similar to an hourglass around them.

To star hop to two other prominent winter constellations, follow the line of Orion’s belt up towards the red star Aldebran, which is the left eye in the constellation Taurus the Bull. In Mythology, Orion is often depicted as fighting the Bull. Similarly, follow the line of Orion’s belt down towards the bright star Sirius, also known as the Dog Star. Sirius is the brightest star in the night sky, and is also therefore the brightest star in the constellation Canis Major (in mythology often depicted as one of Orion’s hunting dogs).

aldebranPhoto credit: Stellarium

siriusPhoto credit: Stellarium

By following these guidelines, and expanding on knowledge you already have, it soon becomes easy to begin tracing many well-known constellations. After you are familiar with the easier constellations, consider getting some simple star charts (planispheres) in order to find more difficult stars and constellations.

Winter is a great time to view the night sky, and River Bend offers a wonderful view from the prairie loop trail and the overlook trail. And if star gazing is something you’d like to learn more about, attend River Bend’s upcoming Winter Fest ( http://www.rbnc.org/winterfest/ )—new this year will be presentations on star gazing, with a chance to put your skills to the test! Also coming up will be a traveling celestial show to be hosted at River Bend on January 27th (http://www.southernminn.com/faribault_daily_news/community/article_6535d35f-d6b3-5a89-919b-a981a67de6bf.html ).

 

Have other tips and tricks for finding stars and constellations? Please share them in a comment!