The Sap is Running

"Sap's Runnin'" is a comment heard all over the state during this time of year. Our recent warm days and nights below freezing create the perfect conditions for pressure to build up in the sapwood tissues of our resident maple trees. The warm days increase the pressure within the tree forcing sugar rich sap upward toward the crown where it will be used to fuel the production of this year's leaves, flowers and fruit. Cold nights cause a decrease in pressure within the tree pulling water in through the roots and setting up the next day's sap "run". The sugar within the sap was produced the previous year through photosynthesis within the now decomposing leaves, then stored for the winter in the tree's roots. In a way, when you sample some real maple syrup, you could say you are tasting some of last year's sweet sunshine.

Trees and the Maine Forest students tap a campus maple.

Maine is the third largest producer of maple syrup in the United states although our production here in the U.S. is dwarfed by that in Canada who produces 75% of the global supply annually. I worked each spring as a high school and college student collecting sap and producing maple syrup at Snell Family Farm in Buxton and enjoy passing on this springtime tradition to my students today.

The sap began running as soon as the spile was inserted into the tree.

We recently tapped a couple of sugar maple (Acer Saccharum) trees right here on campus at T.A. While there are no wild sugar maples large enough to tap in the T.A. Forest, there are two large specimens growing right on campus that were most likely planted decades ago. Nearly any species of maple can be used to make syrup but sugar maple is preferred due to its higher sugar content and fine flavor. Sugar maples generally produce syrup at a 40:1 ratio. This means we will need to collect about 5 gallons of sap in order to produce a pint or so of syrup, just enough for an ice cream party. It will take hours of boiling to remove the excess water and achieve our tasty reward. Stay tuned for a post detailing the boiling process.

A sap collection bucket hangs on an old campus maple.

Fresh Snow Makes for Great Tracking

Our recent light snowfalls have made for great tracking conditions in the T.A. Forest. An inch or so of snow is all that is needed to document the passing of winter wildlife. Any more than a few inches can make determining the species that left the tracks much trickier. On our latest trip outdoors, my semester 2 wildlife students were treated to a variety of tracks on and around the eastern trail. Gray squirrels have expectedly been out and about on the warmer days, visiting our feeders and digging for acorns buried last fall.

Gray  squirrel tracks in the T.A. Forest

A big part of identifying a track is understanding the way each creature walks, also known as gait pattern. Maine mammals can be broken into four distinct groups including diagonal walkers (dogs, cats, deer), bounders (weasels), gallopers (squirrels, rabbits), and striders (bears, raccoons, porcupines, skunks). The gray squirrel is a classic galloper in that its hind feet often land ahead of its front feet as it runs. The tracks seen above are typical of this gait pattern. It can be hard for beginners to decipher which direction a galloper was headed as we expect the larger hind feet to be in the back. Careful observation of the direction the toes point will clear up any confusion. The squirrel tracks shown above point to the upper lefthand side of the frame. 

 Raccoon tracks in the T.A. Forest

Our most exciting discovery last week was this fresh set of raccoon tracks meandering from one squirrel feeder to the next. Raccoons spend much of the winter in den sites resting and living off of fat stores built up the previous fall. However, any warm snap will bring them out in search of an easy meal. It was neat to get to see such perfect prints in the dusting of snow. This is a great representation of a "pacer" gait pattern as each foot lands in its own spot unlike diagonal walking foxes and coyotes whose hind feet land perfectly in the tracks created by their front feet.