Nature Notes from Carpenter Nature Center

GREAT news. The Bald Eagle we rescued way back in March is ready to be released. It’ll happen Wednesday August 24th at 9 a.m. at Carpenter Nature Center. Visitors are welcome to watch but parking will be very limited. If you want to see rehabilitated birds of prey released to the wild-please mark your calendar for September 24th when we’ll co-host the annual fall Raptor Release. It’s free, fun, educational and there should be more parking! For more information on the fall Raptor Release please visit the website:www.CarpenterNatureCenter.org

Black-and White Warbler

ABCD

Some people would say

Stripes of black and white on gray

Are dull coloring

ABDC   

But clearly, they

Have no taste for elegance—-

Or haven’t seen me !

 

Poetry by Linda Whyte & photography by Joanna Eckles.

Taken at Hok-si-la Park on 5/7/11 as the Carpenter Nature Center bird banders did an educational session on bird banding.

Text by CNC intern Summer Hendrickson, photos by Mary Marty

Maple Syrup: A Brief History

The practice of collecting maple sap and turning it into maple syrup is not new. The Native Americans discovered this tree phenomenon hundreds of years ago, likely by accident. Legend tells of an Indian chief, who after removing his tomahawk from a maple tree, set out for a day of deer hunting. When his wife needed to collect water for the evening’s venison stew, she found a birch-bark bucket full of water under the maple tree. The ‘water’ was cooked with venison from the day’s hunt, and produced the sweetest, most wonderful stew the chief had tasted. His wife had unknowingly used maple sap, which is as clear as water, and boiled it down into a sweet syrup. Maple syrup was born! Native Americans often boiled the syrup even further to create maple candy and sugar, both easier to transport than liquid.

When Europeans arrived in North America, they learned from the natives about maple sap and syruping. They experimented with collection methods, eventually drilling holes and using wooden spiles (spouts) and buckets. In the late 1800’s children were given a holiday from school in mid-March. This “sugaring off” holiday was to both celebrate the sap run and to allow kids to help with the laborious process.

The tradition of March maple syrup season is still alive. Collection and processing methods have evolved, although the fundamentals prevail. Sap flow may have been mysterious to the natives and pioneers that followed, but present-day scientists have been able to provide some explanation.

The Science of Sap Flow     

To quote from the North American Maple Syrup Producers Manual, “The physiology of sap flow in maple trees is a complex biological process which is not completely understood.” A bit of mystery still remains, allowing us to wonder at the magic of nature.

Inside a tree are several distinct layers. The phloem layer sends water and sugar, made by the leaves via photosynthesis, down to the roots for storage. In the spring the xylem layer sends water and sugar up the tree to help buds open. The xylem is also called the sapwood, and the sugar-water is known as sap. The key factor that causes sap flow is temperature fluctuation above and below freezing. Freezing nights and warmer days produce flow; maple stems are provided water, then cycle through freezing and thawing. Conflicting sources debate if root pressure is a factor.

Many of us wonder if spring sap flow is exclusive to maple trees, and if so, why? The answer to this question is a bit obscure. Trees in the maple family, and others that give off sap, have air-filled fiber cells and water-filled vessels. Species that do not ooze sap, like ash, oak, and elm trees, have water-filled fibers and gas-filled vessels.  While birch trees exude sap in late spring, the process is not temperature dependent but based on root pressure. Birch syrup is produced in some regions of Alaska, Canada, and Russia. The ratio of birch sap to syrup is even higher than that of maple.

Sap to Syrup

 After the right trees are drilled and outfitted with metal spiles and buckets, sap collection and processing can begin. The water-like maple sap needs to be boiled, allowing a majority of the water to evaporate off, leaving behind a concentrated sugar solution. The sap is boiled until 66.7% sugar remains. This is the legal standard for maple syrup. Syrup boils at 219º F, 7 degrees higher than water. This heating process imparts the darker color and flavor of maple syrup. A higher sugar percentage in the sap will result in lighter colored syrup. A lower sugar percentage in the sap will result in darker syrup, as it was boiled for a longer time. Flavor varies as well, from tree species and boiling times.

The standard ratio for determining how much sap is needed to produce how much syrup is given by 86:1. This ratio is for a 1% sugar concentration in sap. For sap with 2% sugar, the ratio becomes 86:2 or 43:1. So, with sap at 2% sugar, 43 gallons of sap is needed to produce 1 gallon of syrup. Commercial maple syrup producers generally harvest sap from sugar maples with a sap sugar concentration of 4 or 5%. At CNC, where boxelders are the primary maple specie, and production is done for educational purposes, sap sugar concentration is often 1 or 2%.

Programs at CNC Spark Curiosity

 Getting children and adults out to learn about maple syruping has been a highlight this March. The sugar bush at CNC has been providing both sap flow and fascinating programs for over 25 years. Field trips and public programs allow visitors hands-on experience tapping trees, as well as a look at the evaporating process. Interest and curiosity trigger many common questions- some I hope can be answered by this writing.

One such inquiry is how long will it take one tree to produce enough sap for a gallon of syrup? As you may guess, the answer is not straightforward, and varies widely. However, by counting the drips of sap coming off a spile, it can roughly be determined. For example, if one spile drips 60 times a minute (this has been observed several times this season), say for 8 hours a day (only during warm hours) it would produce 28,800 drops per day. We determined the sap has a 3% sugar concentration, which takes roughly 30 gallons of sap, or 384,000 drops, to produce a gallon of syrup. In this scenario it would take over 13 days to collect 30 gallons of sap which converts to one gallon of maple syrup from one tree!

Maple syruping is clearly a complicated and endlessly interesting process. I have enjoyed learning about it and teaching others. So far this season over 40 gallons of maple sap have been collected. If enough syrup is produced for educational sampling next year, CNC’s maple syrup will be for sale in the Apple Shack this fall.

Sources:

North American Maple Syrup Producers Manual

Wisconsin Natural Resources magazine, February 2010

Biology of Sap Flow, St. John’s University Maple Syrup WebSite

Carpenter Nature Center’s Maple Syrup naturalist guide  

AlaskaBirchSyrup.com

Yesterday, during the snowstorm, we received a call from one of our longtime ‘Friends of CNC’ who lives up the valley. There was an injured eagle sitting in the snow near her birdfeeders. As a former Carpenter Nature Center wildlife rehabilitation volunteer she knows eagles and injured animals. The adult eagle wouldn’t fly when it was approached and there was nobody at the residence physcially able to capture it to transport it to The Raptor Center. Carpenter Nature Center is extremely short-staffed due to funding cuts and we usually cannot rescue injured animals. Typically we work with the Wildlife Rehabilitation Center of Minnesota and The Raptor Center at UMN to help get the injured animals to the appropriate facility. Unfortunately yesterday the road conditions in St. Paul were so bad that the regular rescue volunteers couldn’t get out to rescue the eagle. As we were already in the area we decided to give it a try.

 Jim Nielsen (CNC advisory board member), Jen Vieth (CNC Development Director) and Pam Cook (CNC volunteer) went to the residence and assessed the situation. The eagle looked pretty bad, with dried blood all over its face. He was hunched over, his feathers were fluffed up, but his light yellow eyes were wary and alert. We decided he did need to be captured instead of spending another evening in the wet and cold snow.

We formed a plan to surround him and Jen would come from the downhill side to capture him. The plan lasted about 26 seconds as the eagle ducked under a fallen tree and ran through the woods towards the river and a neighbor’s house.

After a very snowy chase down the hill we ended up capturing him right beside a sculpture. It was quite a surprise for the neighbors to see three people bursting through the quiet, snowy woods towards their home to wrestle an eagle to the ground in front of their patio window!

We loaded the eagle into a crate and into Jim’s truck for the drive back to Carpenter Nature Center. By the time we got him back to CNC the roads were clearing enough that The Raptor Center was able to send a WONDERFUL volunteer to pick the bird up and take it back to the clinic. (THANK YOU!!!)

While the eagle didn’t look good, and smelled worse, we knew his best chance of survival was getting to The Raptor Center’s clinic as soon as possible. We’ve got our fingers crossed that he is ‘repairable’.

An update from Dr. Juli Ponder at The Raptor Center 3/25/11:

“The eagle is alive, has puncture wounds (suspect territorial dispute) and a coracoid fracture. As well as low level lead poisoning. It is being treated for the lead poisoning and coracoid fracture, receiving wound care and supportive treatment (not yet eating well on its own). At this point, we have not identified anything that would lead us to believe the eagle’s treatment will not be a success.”

 

 

Near shore’s edge a log gleams

With what seems polished, jade stones, like

A brooch glistening on a blue-draped breast

The dazzled hiker halts

Breath caught, muscles taut

—too late!

The log rocks, spilling living gems

That slip silently into the silken folds

Of a liquid stronghold

With no more trace of the treasure

Than rings that ripple and radiate

Like the waves of remembered pleasure

Poem by CNC volunteer Linda W. & photo by CNC volunteer Sue P.

The focus of our mission at Carpenter Nature Center is teaching others about the natural world. The majority of those we teach are K-12 students, yet they are not the only people who benefit from our programs. Here is a great essay from a former environmental education intern, Katie-Lyn Bunney:

While this is not my earliest memory, it is one I can bring quickly to my mind: I’m about 5 or 6 years old. It’s springtime and there are a plethora of muddy puddles around my house and school, made by melting snow and rain, and the indentations of tire treads in the soft ground. It was a frequent outdoor pastime of mine, looking into these watery worlds; I’d spend hours moving from puddle to puddle (some were quite large) with my trusty stick in hand, poking and prodding around the leaves and mud to see what I could find.  

I think that is where my appreciation of nature first started. I don’t recall if I found much beyond the decaying leaf or occasional larvae or frog spawn, but I loved doing it. The idea that something, anything, could thrive in a place that was so tiny and (to me) barren, was fascinating. 

As I grew older my fascination moved from things in puddles, to things I’d find in the grass or on trees or even in the dirt. I still laugh at myself, though, because for the longest time I was terrified of earth worms. But still, I looked for them and their other dirt companions. I never knew what many of these things were called beyond the basic worm, bird, bug, or tree.

Now, of course, I know better. I can name birds and insects and trees just by sight (something that seems to amaze many of my family members, but to me is just second nature by now). But my love of nature has never wavered. In high school I took every earth science class that was offered–I could learn about the ocean and geology and zoology (physics and chemistry still stump me). I soaked up every minute of it.

I have no idea where this love of the outdoors and all things nature came from. My family would be completely lost and probably highly uncomfortable if I told them I was taking them to spend the day in the woods–no toilet, no video games, no lawn chairs–just us and nature. I think the bugs alone would scare most of them off in about 20 minutes. Some of my more recent friends and acquaintances (even co-workers) may be surprised to know that I had never even gone camping until college, especially knowing how much I love it now. It wasn’t that I hated it growing up, but the only real exposure I had to it-since my family didn’t camp or hike-was through Girl Scouts, which was sleeping on a platformed canvas ‘tent’ with cots and bug nets.

But I had the privilege of having some of the most nurturing teachers throughout my school years. My science teachers fueled my curiosity and encouraged me to find more, to look things up, to take this class or that class. I will be forever thankful to those teachers for always making science and nature something interesting to me and not dampening my natural curiosity for them.

That curiosity led me to college here in the great state of Minnesota. I had some wonderful experiences during those years. But one that stands out the most is when I realized that what I wanted to do most was to teach others about all these things, to be to someone else what all my teachers were to me: someone who could inspire curiosity and appreciation about things they may not have even thought of before, but especially about nature.

This wasn’t just a moment of epiphany; it was more of a gradual realization throughout my sophomore year of college. I was taking chemistry and biology courses (which were interesting, of course) but I was realizing that they would only lead me to years of work in a laboratory with some occasional field work if I was lucky. I knew I didn’t want that, so I switched from Biology to an Environmental Science major, hoping I’d be able to work outside.

It wasn’t until I got my job at a local natural history museum, and then again later during my internship at Carpenter Nature Center, that I realized that teaching about all those interesting nature tidbits was what I really wanted to do. One of my greatest joys is seeing that spark of understanding in kids’ eyes when they realize how connected everything is to everything else, when they finally see that getting rid of all those bugs we may hate flying around our heads in the summer can actually affect things we wouldn’t want to live without. The bees pollinate flowers that give us fruit like strawberries and apples; fish sometimes eat those bugs and still more animals eat those fish, and so on and so forth. And whose to say that something we do today won’t have an affect on an ecosystem fifty years from now? Rachel Carson’s “Silent Spring” comes to mind.

I absolutely love what I do. I feel so lucky to be someone who connects people to nature. How many people get to say that they spent the whole day outside on snowshoes looking for animal tracks, or with their feet in a mucky pond digging up insect larvae and loved every minute of it?

No one could have told me all those years ago as I poked through those puddles that I would one day get to do that, and teach about it, for a living. I wouldn’t have believed them. I wanted to be an archaeologist and was absolutely sure I’d be digging through the sands of Egypt looking for mummies. At five years old the idea that someone got to play outside all day for work seemed absolutely ludicrous. It still does, but I’m not complaining!

So next time you see one of your children or grandchildren or nieces or nephews getting dirty in a puddle, let them. Join them. See what you can find. Or if you don’t like the mud, move somewhere else. Come out to Carpenter Nature Center, if you’d like–we’ve got plenty of nature to go around! Take a good long searching look around you. Try to find something you’ve never noticed before. Maybe you’ll see a woodpecker in the tree, or some tracks showing scuffle between fox and rabbit. Perhaps you’ll take a look at the sky and see a Bald Eagle soaring over the river. You’d be surprised at what you notice if you take the time to look. Share the experience with someone. It could turn out to be a life-forming one, like mine was for me.

As we humans hunkered down in a state of semi-hibernation during the recent cold snap, our wildlife was foraging, staying warm, and preparing for another busy season of raising young. Even though we see extreme temperatures at this time of year, it is a terrific time to get out and explore the natural world.  The many tracks and trails left in the snow can give you an idea of the diverse wildlife using our parks, trails and yards. A recent hike at Carpenter Nature Center turned up otter tracks near the river! As an added benefit, studies show that even a little time spent active outdoors can improve your mental and physical health.

One of my favorite wildlife watching activities at this time of the year is “Raptor Spotting”. The lack of leaves on the trees makes observing birds of prey much easier. It is quite common to spot a pair of Red-tailed Hawks or Bald Eagles sitting in trees in their territories. Noting their location will give you an idea of where to watch for them in warmer weather. During the winter there are also often Rough-legged Hawks in the fields south of town and occasionally even a Snowy Owl or two. This year there has been a Snowy Owl hanging out in fields near Northfield, Minnesota. A trek to the Sax Zim Bog area near Cloquet is also a great place to watch for winter rarities such as Northern Hawk Owls and Great Gray Owls. It’s odd to think that for these species, Minnesota is their “Florida winter vacation” and that they will head further north as the weather warms up.

Once you have spotted a pair of raptors using a territory you may be able to locate their nest, which will make for fun wildlife watching once the birds start raising a family. Typically hawks and eagles have one or more nests on their territory which they build themselves. The pair returns season after season, adding a little bit to the nest each year. A few Bald Eagle nests reached record dimensions: 10 feet in diameter, 20 feet in height and each weighed over 2 tons! A trick to determining if you are looking at a raptor nest or a squirrel drey is to look at the shape and composition of the nest. Typically raptors and crows have nests with flat tops made mostly of sticks. If you see a large nest that has a ball shape with lots of leaves, it is most likely a squirrel’s home.

Every once in a while a nest watcher gets a fun surprise. A few years ago there was a large stick nest with a flat top at the south west corner of General Sieben and County Road 46 in Hastings. While it was most likely built by a Red-tailed Hawk, the bird raising chicks in it that year was a Great Horned Owl! Great Horned Owls do not build their own nests, and simply take over someone else’s hard work when its not in use. December through February is a great time of year to listen for owls in your neighborhood. The pair of owls that “owns” the territory will often hoot to let other “invaders” know that this site is taken. You might even be able to tell if you have both a male and female owl in your area. Amazingly scientists have determined that the larger female Great Horned Owls have a higher pitched hoot than the males. (Thanks to Chris Mueller and Kristy Clarke for the portrait of the Nature Center’s Great Horned Owl.)

In Hastings we have quite a few Bald Eagle pairs and you may spot a few nests from the walking paths near Lock and Dam #2.  One of my favorite nests to watch is along County Road 46. Sadly after at least 2 years of successfully raising young, the pair’s nest was blown down in one of our late season storms. I was happy to see that the pair started rebuilding their nest in the early winter and they can often be spotted sitting near the nest these days.

Looking ahead there are lots of great things to do outdoors this winter, from Moonlight Snowshoe Hikes to March’s Maple Syrup Making programs. Or just a hike, ski, or walk outdoors on the trails at one of our many local parks. If you are as interested in raptors as I am you will be sure to enjoy Carpenter Nature Center’s “Owls and other Masters of the Sky” programs in March. Until next time-I hope to see you on the trails….

It has been a busy October at Carpenter Nature Center.  So busy that the Apple Shack sold out of apples early this year. Usually ‘The Shack’ is open until Thanksgiving, but this year the doors closed for the season on Monday. 

Bird migration has also slowed down and now we are just waiting for some of those interesting winter specialties to show up. I’m personally hoping for Crossbills again this year-but I think that may be a little overly optimistic as the are no predictions of a Crossbill Irruption this year. The Winter Finches, which includes species such as Redpolls, Pine Siskins and Crossbills, aren’t predictable annual migrants and tend to move more based on the seasonal variations in seed and cone crops. In one winter we may see hundreds of Common Redpolls at Carpenter Nature Center, then we won’t see another redpoll at the center for 5 years. If you are curious about which finches might venture south to our area, please visit the Winter Finch Forecast: http://ebird.org/content/ebird/news/ron-pittaways-winter-finch-forecast-2010-2011 

One of the heralded signs of warmer weather are our beautiful, bold Eastern Bluebirds. While most of the bluebirds have flocked up and headed south, there are a number of tough little bluebirds who spend the whole winter in our area. When I worked at Cardinal Corner Bird Store in Newport, we had reports of bluebirds throughout the winter. 

Please enjoy the following poem about bluebirds by CNC volunteer Linda Whyte.

Browns and Beautiful Blues

 

Everywhere in the river-bottoms,

A study in brown

 

the forest floor, a carpet of leaves

Strewn around,

Russets, tan and beige

On sandy ground

 

The tree-trunks, an earthen

Ash brown,

Reflected in flood-swollen

Muddy waters

 

Only the warm late-autumn sun

And occasional patches of golden green

Alter the scenery’s mood

From somber to subdued

 

Until…a tiny blaze of sapphire blue

Flashes into view,

Like a piece of clear sky fallen

Among the trunks

 

Then blown back up

And caught in the tree limbs.

Suddenly, bursts of blue

Are popping everywhere

 

Splashing the woods with glorious color.

The sapphire gems, offset with

Blood-red and bright white

Have come to life

 

And the water-reed calls

Of bluebirds ring in sweet profusion.

 

If you are venturing out and about to enjoy the last warm days of the season-drop by Carpenter Nature Center or one of our many terrific local St. Croix Valley orchards this weekend. The weather is spectacular, the apples are ripe, the pumkins are a glowing orange and the fall foliage is alive in yellows, oranges, and reds. While Carpenter Nature Center is open to the public every day we only host Apple Fest this weekend. Other St. Croix Valley orchards celebrate Apple Fest during most of the early October weekends. Each orchard has their own specialty from corn mazes to animal petting areas to eco-friendly, minimum spray apples. Call ahead to find out if your favorite orchard is open, and what special events they have planned for the harvest season.

Visitors to Carpenter Nature Center’s Apple Fest can enjoy music, critter programs, hay wagon rides with Sven & Ole, hiking the trails and sampling some of the many ‘minimum-spray’ apple varieties grown at Carpenter Nature Center. Along the trails the purples of the blooming asters are lovely against the background of golden prairie grasses and flaming red sumac. In the trees migrating warblers can be spotted, adeptly harvesting insects from the leaves. In fact a little Yellow-rumped Warbler perched outside my office window as I was proof reading this post!

 On Saturday there were an estimated 1,750 visitors at Carpenter Nature Center’s Apple Fest and we anticipate at least 1,000 more on Sunday. There is no fee to visit the nature center or Apple Fest but there is a charge for the apples and some of the activities, such as face painting. All proceeds support environmental education programs for local K-12 school children.

Please stop by and say hello!