Using the Biltmore Stick

As spring rolls along in Trees and the Maine Forest class, we wrap up our study of tree identification and begin to apply our new skill to the T.A. forest. With the ability to identify all of the species present in our woodlot, students can begin to explore the ecological and commercial values of individual trees. Along the way, students learn to use a specialized forestry tool, known as a Biltmore stick, to measure and estimate a tree's commercial value.

Chance and Hannah work together to measure a tree in the T.A. Forest.

The Biltmore stick has multiple uses in the woods and is an important tool for any forester cruising a woodlot in an effort to estimate stand value. The stick is calibrated to help students first estimate diameter at breast height, or DBH. This is the diameter of the tree at 4.5 feet above the ground. To do this, the stick must be held 25 inches from the eye and lined up so that the left end of the stick lines up with the left edge of the trunk. Then, without moving their head, students peer over and observe where the right side of the trunk intersects with the stick. The Biltmore stick is calibrated based upon laws of trigonometry to give a very accurate estimate of diameter when used correctly.

Proper alignment of a Biltmore stick on a tree with a DBH of 14".

Ares flashing perfect form while measuring DBH.

Once the DBH has been determined, students step back 66 feet, or 1 "chain", from the tree and hold the stick vertically with the base of the stick lined up at what would be the stump height.  The stick is again marked at intervals based upon trigonometry to show how many 16 foot sawlogs are present in a given tree. Here, students must be able to judge where a tree goes from a merchantable log to firewood.

A red maple with one merchantable sawlog. Everything above the number one could be used for firewood. 

Seth works to determine the number of sawlogs in a tree after stepping back 66 feet.

Finally, the Biltmore stick has a table printed on it that indicates the rough volume of wood present in a tree based upon its DBH and the number of sawlogs. These numbers are given in board feet, the common unit of volume for lumber. One board foot is 12"x12"x1".

A look the markings on a Biltmore Stick.

Students in Trees and the Maine Forest recently worked to complete an assignment in which they determine the value of ten trees flagged in the TA forest. They must first determine the DBH and number of logs in each tree, then utilize the table on the Biltmore stick to calculate how many board feet of lumber are in that tree. Once the volume of lumber from each tree is determined, they utilize the most recent timber values available for our area to estimate monetary value of each tree. When all ten tree values are combined, students are often impressed with the value of our forest resources on campus. This leads to great conversations on woodlot management to maximize commercial value as well as wildlife habitat. When done correctly, both wildlife and property owners can benefit from thoughtful harvest. Learning to use the Biltmore stick is not only a cool skill for my students, it also helps to change their frame of reference when walking through the forest or even their neighborhood. I love hearing stories about high value trees that students have observed around town, there is no better sign that concepts from class are truly sticking.

Special thanks to Allie Gross for her photography in this post.

Silver Maples in Bloom

There have been brief tastes of spring warmth this season, but for the most part, cooler temperatures have prevailed. However, hidden within all of the cold and wind is a sure sign that milder days are ahead. Over the weekend, the silver maples (Acer saccharinum) in our area began to flower. There is a typical progression in the bloom of Maine's forest trees throughout the year. Silver maples are one of the first whose buds pop open to expose their reproductive structures. Some trees have only male or female flowers (dioecious) while others have both on the same tree (monoecious). The blossoms shown below are female, or pistillate, flowers from our lone silver maple on campus.

 Female flowers from our campus silver maple just beginning to show.

Our single silver maple is located along the sidewalk in front of the latin building and provides a perfect specimen to share with students during our walks focused on tree identification. Structurally, silver maples are known for their light gray, loosely plated bark, and long pendulous branches. 

Our campus silver maple in bloom on a snowy April morning. 

One of the coolest parts of sharing tree identification with students is providing them with an additional layer of wonder in the outdoors. I try to help them associate each species with the types of habitats they will most likely be encountered in. If they can connect a given species with a memory from their experiences in the Maine woods, future identification becomes much easier. Personally, I can't think of silver maple without memories of hard fighting smallmouth bass on evening drifts down the Saco River. Silver maple grows best on sandy soils along the banks of streams and the Saco River is lined with this species in many areas. Its long branches hang out over the water in their pursuit of sunlight. This provides a shady hiding spot for bass to ambush baitfish and await the drop of insects from the branches above. As a youngster, my father would paddle me along down the river as I casted to hungry "smallies" hiding under the limbs of those silver maples. As a kid, I had no idea what tree species those bass were coming out from under. My only concern was that they were there and willing to play along. My Anglers' Society kids tend to think in the same fashion. The hope is that through their experiences on the water and in the classroom, they too will begin to assign value to each species in their own way. That value provides motivation to conserve Maine's natural beauty for the next generation. 

Julien shows off a fine smallmouth from the Saco River. Off in the background, silver maples glow in their classic yellow autumn colors.   

Big Night!

As I write this post tonight (3/31/19), it is 48 degrees with a steady rain falling. These are classic conditions for "Big Night", an annual migration of amphibians in the Maine woods. For me, it is not officially spring until I've heard the peepers, but by the time their deafening calls are ringing from every local wetland, the legendary big night is already a week or so in the rear view mirror. Wood frogs and spotted salamanders are the first amphibians in our area to awaken from their long winter dormancies under leaf litter or deep underground in the forest. They do so immediately looking to reproduce. The terminus of their migration is a vernal pool. These are seasonal wetlands brimming with recent snow melt that provide critical nursery habitat for fast developing frog and salamander larvae.

 A wood frog hiding along the bank of a vernal pool

Not every big night is created equal. On years with little rain and a gradual early onset of spring temperatures, the breeding activity can be drawn out over the course of a couple of weeks. This year has set up to be a great one as cold temperatures have hung on into late march culminating with two warm days and a rainy night. You can bet that thousands of wood frogs and spotted salamanders will be on the move in southern and coastal York county this evening.

A spotted salamander encountered on a class trip to the vernal pool

The way the schedule shook out this year, it will be the first time in a quite a while that I have not taught at least one section of Maine Fish & Wildlife in the spring. Vernal pools are always a big part of my spring curriculum in MEF&W. Few other units provide such a direct opportunity for the creation of a memorable learning experience. Students can be introduced to a suite of creatures in the classroom, then head out the door to see and hear them, all in the same block! As we enter the fourth quarter, we will get outside more and more to refine our identification and measurement skills in Trees & the Maine Forest. You can bet that I'll swing by our own vernal pool in the TA Forest with my classes. There is a big old quaking aspen along its bank that I always make sure to show the kids. It provides the perfect excuse to check in on some old friends.

Nighttime Cusking with the Club

The Thornton Academy Anglers' Society recently visited Sebago Lake in search of cusk. Freshwater cusk (Lota lota), also known as burbot or eelpout, are members of the same order that cod and haddock belong to (gadiformes). They are the only member of this order found in freshwater and inhabit deep, clean lakes across the northern hemisphere from Maine to Siberia. Here in Maine, cusk fishing is done during late winter through the ice at night. It is at this time that cusk move into shallow areas under the cover of darkness to feed and spawn. Throughout the rest of the year, cusk are rarely observed as they seek deep, cold water. These fish are notorious for feeding on everything from smelts to crayfish but are most often targeted using dead bait on bottom. They are fine table fare and make for an awesome chowder. Because of the limited number of waterbodies that support cusk populations and the need to fish for them at night, cusk fishing is usually a first for most of our members.

Cusk outings are a nice change of pace in that we left campus at 4:00 p.m. rather than the usual 6:00 a.m. The plan was to arrive at the lake in time to get set up in the waning daylight knowing the cusk should start biting once it is completely dark. After setting up, we enjoyed a classic supper on the ice consisting of red hot dogs and homemade venison chili. The fishing ended up being tougher than we had hoped and we got a taste of why this lake is referred to as "Slowbego" by many. Amelia Pellerin saved the day with a beautiful 19" cusk midway through the trip. This fish ties the all time record for this species at T.A.!

 Amelia with her 19" school record cusk

Amelia's cusk gave us hope that the bite would pick up but it wasn't meant to be. Just as things started to seem like Amelia's fish would be the only one on the night, a flag on a distant trap was spotted. After a sprint to the hole, and a long battle, Nate Lilly hauled a 25.5" togue onto the ice. Lake trout (Salvelinus namaycush), or "togue" as most Mainers refer to them, are most often found in deep water and feed mainly during daylight hours. Sebago is a known destination for togue fishing but nearly all fish are caught during the daytime. I have heard legends of nighttime togue being caught but never seen it myself. Needless to say, Nate is in rare company with his feat.

Nate with his 25.5" Sebago togue

Sebago has a way of humbling even the most experienced of anglers from time to time. Whenever I hit the big lake and am able to put just a single fish on the ice, I consider the trip a success. In the end, outings like this one are more about building friendships, learning new skills, and creating lifelong memories. The hope is that our members gain the experience necessary to someday take advantage of this unique fishery on their own, continue to care for the resource, and keep our local outdoor traditions alive.  

A Great Day Smelting

Rainbow smelts (Osmeris mordax) are found in a variety of habitats in Maine from well oxygenated lakes to tidal estuaries. They feed mainly on plankton and tiny crustaceans and provide an important food source for a variety of predatory creatures such as landlocked salmon, mink, loons and many more.

A freshly landed sea smelt

The Anglers' Society got out over the weekend at Leighton's Smelt Camps in Dresden chasing sea smelts. "Smelting", as most fishermen refer to it, is a winter tradition in Maine. There are a handful of commercial smelt camps in the vicinity of Merrymeeting Bay where one can rent a shack for a six hour tide in hopes of catching smelts. Lines are usually hung from the ceiling baited with cut sand worms and fish are hand lined in when a sign of a bite is detected. When the fishing is good, it can be hard to keep all of the lines in the water.

Tyler, Amelia, Sierra, and Destiny briefly took their eyes off the lines for a photo. 

The smelts we were chasing are the same species found statewide. However, these "sea smelts" spend part of their lives in a saltwater estuary feeding and growing to a larger average size before running back up river to tributary streams for their spring spawn. Their natural migration from a natal freshwater river to the ocean and back again makes them Anadromous. We have many native anadromous species in Maine including but not limited to atlantic salmon, striped bass, alewives,  lampreys, Atlantic and shortnose sturgeon. Sea smelts spend the winter under the ice of frozen tidal rivers awaiting their spring spawning runs into smaller tributary streams. Mainers have utilized this food source for generations dating back to the Native Americans.

Jake with his first smelt

We fried up and ate some smelts on Saturday and kept some for bait on upcoming outings. We even brought three home alive as the newest addition to Mr. Bryant's touch tank in the Marine Biology classroom. They have adjusted well to the tank and serve as great ambassadors to an often overlooked migratory fish species found in nearly all of Maine's tidal rivers.

The newest additions to the T.A. touch tank

A Winter Walk in the Woods

We wrap up the Maine Fish and Wildlife course with a mini unit on winter survival and ecology. I struggle to express just how amazing it is that creatures are able to survive the rigors of a Maine winter. The adaptations they possess to get them through are truly awe inspiring. With students having wrapped up their final exams, we spent the last classes of the semester in the T.A. forest looking for signs of life in a winter landscape that can seem desolate at first glance. With a lack of fresh snow on the ground and bitter cold keeping everything frozen solid, tracks were not as prevalent as they could have been but there were certainly some prints left over to analyze.

An old fox track preserved in the snow

A pair of coyotes crossed the once slushy venal pool leaving evidence of their travel frozen in the ice

I had hoped to show kids some signs of porcupine activity in a traditionally productive spot. These winter survivors are at home in the trees and prefer large eastern hemlocks in the winter. The tree's naturally thick branches provide a wind break and the hemlock needles are an important winter food source. Fresh cuttings of hemlock twigs and ample oval shaped scat pellets on the ground are a sure sign of porcupine activity in the winter. Individuals can spend days or weeks in the same tree  creating an obvious buildup of scat and twigs. Deer, who yard up for the winter in the same type of habitat, benefit from the hemlock twigs dropped to the forest floor by the porcupines. 

Discarded hemlock twigs and porcupine scat led us to the active trees 

Luckily, we quickly found signs of porcupine activity. I put the kids to work scouring every nook and cranny of the hemlocks with the most sign underneath them. Eventually, we located two porcupines resting in the same tree. After a closer look through binoculars, what initially looked like a nondescript dark blob materialized into a snoozing creature unimpressed by the sudden commotion below. It is not every day that plans involving wildlife work out so perfectly. Just finding the evidence of feeding porcupines would have been great but to locate and observe two felt extra special. I brought my camera with the long lens hoping to get some photos of the porcupines on day two but they were not as cooperative for my maroon day students.

Students gaining an appreciation for the challenges Maine's wildlife face in winter

Special thanks to Allie Gross for freezing her fingers off taking photos for today's entry.