When the first days of March roll around in northern Illinois, many of us search desperately for the first signs of spring. For some, it may be the green “sprouttles” of spring beauties thrusting themselves out of the leaf-matted soil. For others, it might be hearing the two-toned territorial call of a chickadee or the pungent smell of skunk cabbage. For many, it may just be the feel of mud squashing under their boots on the hike to find any and all signs of early spring.
For me, the first sign of spring is not something you can see, hear, smell or feel. It is what is happening in silent mystery beneath the bark of the sugar maple trees—the first run of sap. This typically occurs in Lake County around Valentine’s Day, far before anyone is thinking about spring.
I overheard many assumptions that the mild winter this year would lead to poor syrup production. Turns out, that wasn’t the case. The staff at Ryerson Conservation Area has made seven gallons of syrup so far this season (we typically make anywhere between four to 10 gallons a season)! To back up my personal experience, I contacted Timothy D. Perkins, Ph.D., Professor & Director, University of Vermont, Proctor Maple Research Center, to question whether mild winter weather can affect the production of maple syrup. Here is a portion of his email response:
“It should have relatively little impact. Ninety-nine percent of syrup yield is related to the weather we have DURING the sap flow season, with little else (other than major damage to the tree) affecting it outside of that. We can’t tell for sure when the season will start or how long it’ll last until after the season is over. Weather forecasting only extends out a few days—we can’t do any better than that.”
It boils down to this—as long as the nighttime temperatures dip below freezing and the daytime temperatures are above freezing, we at Ryerson can count on syrup production. Once temperatures increase the sap from the trees turns cloudy, no longer producing a sweet syrup, and the season is over. Sap season typically lasts only two to four weeks.
How does it all work? When these temperature changes occur, pressure is created inside a tree. Sap produced in the leaves the previous summer is sent up networks of tiny tubes. This is when, for over 35 years, the staff at Ryerson Conservation Area pulls out their drills, hammers, spiles and buckets and sets out to tap about 30 sugar maple trees.
Using a 7/16–inch bit, we drill a hole about ¾ to 1 inch into the tree, clean the hole out with a “special tool” (i.e. a little twig), place the spile (spout with a hole on the bottom and a hook for a bucket) in the hole and tap it in with a hammer. Then, we simply hang a bucket and wait. To watch the process in action, watch this short video of Ryerson’s tapping day this year. Or, if you have a maple tree in your yard (any kind of maple tree will work, but sugar maples are sweetest) and are interested in trying it out for yourself, here is a great step-by-step guide to tapping a tree.
Once the buckets have been hung, we eagerly wait for the distinctive plink-plink sound of the sap plopping into the aluminum buckets. On a good day, the four-gallon buckets can fill to the brim, and then it is cooking time. Much to the dismay of the students that visit our Maple Syrup Program at Ryerson, what comes directly out of the tree is not syrup. Sap in a sugar maple tree is 97% water, 2% sugar, and 1% minerals. It takes a full day of cooking the sap over a wood fire in our evaporator to remove that water in the form of steam and to caramelize the sugars. The end result—real maple syrup, which is 66% sugar. It takes about 40 gallons of sap to make 1 gallon of syrup!
So, like I said, my first sign of spring is not something you can see, hear, smell or feel, but it sure is something you can taste! If you want to see the process firsthand and get a taste of real syrup, come out to the Maple Syrup Programs at Ryerson Conservation Area the first three weekends in March. For more information, or to register visit our calendar of events.