Forest Walk Apr 27, 2024

Drafting…]

Notes & Photos from Forest Walk at Sandy Lake Park, Sat Apr 27, 2024
– David P

Field Trip Guides: Sean Haughian (Curator of Botany, NS Museum) & David Patriquin (Dal Biology prof, retired).

It was a  rapid-fire intro to the area and the plants. I am hoping these photos and notes can be of help to those who wish to go back to the area and have a second look at a more leisurely pace; and to others who might wish to explore the area on their own.

We followed  my now standard route for a ‘Sandy Lake Forest Walk’. It’s an easy walk for the most part,  roughly 2.7 km in total.  This particular event was scheduled as a 2-hr walk (1-3 p.m.) and while that’s readily achievable walking-wise,  3 even 4 hours are required if one wants to spend significant time exploring particular areas, ID ing plants etc. or perhaps doing some  ‘Forest Bathing’.

We viewed and talked about forest ecology and the trees and shrubs, ferns and herbs and the “little plants”- the mosses, lichens and liverworts (Sean’s specialty) – along the way;  the last of us were back at the gate at 5 p.m.

1. The Route

2. Park Entrance  to the Big Parking Lot

We had expected the gate to have beeb opened for us but it wasn’t; I left a note on my car,  which was parked next to the gate, asking participants  to walk down to the Big Parking Lot;  no one saw it,  so participants  assembled by the Gate. As people arrived, Norris Whiston handed out colour prints of his Cobequid Mountain Field Guide to Ferns, Club Mosses, Mosses and Lichens, Thx Norris for a very thoughtful and generous contribution. View more of Norris’s Guides under NW Guides & Keys on the NS Wild Flora Society website.

Sean Haughian arrived (on a bike!) – his second City Nature Challenge event of the day,  and spent about 20 minutes with the group on a patch of barrens by the gate.  He picked up some pieces of lichen and a clump of Sphagnum moss and talked about their structure and  ecological significance; Sean carefully put back the clump of Sphagnum moss before moving on!

I met the group at that point and  we walked down to the Big Parking Lot. We noted Eastern Hemlock, Red Spruce, Red Maple and Yellow Birch trees at the forest edge on the way [re:  A:  Wabanaki Forest Tree Species]. There was no leaf-out of the hardwoods yet; the Red Maple flowers were just opening; and coltsfoot by the roadside was in full bloom.

At the parking lot we talked about the two major types of natural disturbances that impact the Sandy Lake area forest:  (i) wind and (ii) pest/diseases.  (Fire is a minor disturbance of forests on this landscape, but is the major disturbance on droughty landscapes in NS such as the Backlands.)

EXOTIC PESTS & DISEASES One tree species  of the Wabanaki Acadian forest, American Beech,  has been strongly impacted by exotic pests and diseases in the past. Within the last few years, two more tree species (Eastern Hemlock and American Ash) have been attacked by exotic pests with devastating consequences, but not yet at Sandy Lake. At left: Old  beech snag (centre of pic in background). A “snag” is a standing dead tree or part of it; the original tree had a lot of  canker disease.   There are young, apparently still healthy beech trees in the foreground (beech often retain  their leaves through winter). At right: a very large, old American Ash (circa 5 ft diameter)  can be seen in the centre of photo; a young tree  lies just to its left, in the foreground. The old tree appears mostly dead, probably just from natural aging. Young ash trees in the area still appear OK but we are watching for symptoms of Emerald Ash Borer, first discovered in NS in the Bedford area in 2019. Photos taken  on Apr 27, 2024, close to the Big Parking Lot at Sandy Lake.   Mature Eastern Hemlock by road, just past the gate on the way in. At right: no sign of HWA (Hemlock Wooly Adelgid) on the undersides of the needles.   HWA  was first discovered in NS in 2017 in southwest NS; it was reported in the Bedford area in 2023. Photos on Apr 27, 2024

We would be visiting 3 “patches” of Old Growth Forest. The first was a White Pine-dominated Old Growth stand located just off  the parking lot;  there we could view all of the Old Growth features cited in the handout [re:  D: Patches of Old Growth].

We could also see evidence of two types of wind disturbance: Gap & Stand-replacing. Gap Disturbance was illustrated by the spaces  where individual older trees had been uprooted or snapped off by wind and young trees are filling in the spaces. Stand-replacing wind disturbance was illustrated by the pronounced Pit and Mound Topography at the site; it is likely attributable  to blowdown of a Mature/Old Growth forest  during a hurricane in the 1800s; see Mature/OG Forest and Pit & Mound Topography  for more info.

3. Big Parking Lot to the Beach

En route we stopped near the bottom of the road where a stream emerges from the forest and goes under a culvert and thence through another 50 m or so of forest and finally empties into  Sandy Lake. I used a pocket AP2 meter which I described as a “pollution monitor” to measure the temperature and electrical conductivity (a measure of the salt content) in the stream water, then I did the same on the shore of Sandy Lake. Earlier I had made the same measurements on a stream on the side of the road that goes from the Gate to the Big Parking Lot; it carries water from the adjacent forest. The results are shown below.

It’s notable that that water at the site with forest cover  (middle pic) was the coolest. The two stream samples had very low EC. The much higher EC of the lake is due to streams entering the lake that drain developed areas & highways to the south and southwest of the lake. Measurements on Apr 27, 2024. See Links below for more info. about using such measurements to monitor pollution.

4. On to the Drumlin

From the beach, we walked northwest along shore until we reached an old cottage site; then we followed an old logging road/trail that took us up a drumlin through hemlock-dominated evergreen forest. We paused by an old, epiphyte-covered American Beech and  Sean H talked about the some of mosses and lichens – see Sean H on lichens, mosses and liverworts for details. A  little further on we saw examples of the “Wabanaki Forest Love Affair”.

View Group Photo (Several participants had gone back on their own at this point to keep on the 1-3 p.m. schedule so were not in the photo.)

5. The Old Hardwood-dominated mixed Forest

It was at this site that I wanted the group to spend most of its non-walking time. As we walked from the closed hemlock forest on the lake-side of the drumlin to the peak, the forest opened up with more hardwoods (not yet leafed-out), and as we descended on the other side, we were in a hardwood-dominated mixd forest with patches of pure hardwoods. The most common hardwoods are Yellow Birch, Sugar Maple, and Red Maple, with lesser amounts of American Ash and White Birch; there is at least one Ironwood in this area. There are many Strip Maple that extend into the subcanopy.

This stand didn’t quite qualify as “Old Growth”, rather it was classified asa “Mature Climax” stand  when  we did a formal assessment in 2017 as the average age was 104 years (versus 125 years required for Old Growth under the 2012 Old Forest Policy).

However,  the maximum age we observed was 141 years, in line with the maximum age at the Old Growth Pine and Old Growth Hemlock sites we visited, and a pronounced Pit and Mound topography at this site suggests that here, as at the other sites, there was a major blowdown of Old Growth forests circa 150-155  years ago. Red more under Mature/OG Forest, and Pit & Mound Topography.