NAA: Identifying Trees by Their Bark

Disclaimer:
1) I took notes and photos, but I can only be sure the photos match the notes within the limits of my ignorance.
2) Generally I am not directly quoting anybody, unless you see quotation marks. All factual errors are mine!
3) Re: above-Corrections are appreciated!

Though the class was about tree bark, Robert Wesley and Nikki Cerra showed us multiple clues to search for when identifying trees. Since fall has passed, we looked for fallen leaves on the ground and examined buds within reach. Robert suggested binoculars as a regular part of a woods walk, in case the buds are only in the canopy. We saw examples of both shade and sun leaves-due to their relative positions, a tree’s shade leaves may be bigger and rounder than those from sunnier locations. Sometimes these differences are quite dramatic, at least in the oaks we saw.

No single factor is necessarily a sure bet in the identification of a tree species, though when we were running out of time and Robert took off ahead of us, slapping trees as he dashed past and calling out their names, I wasn’t so sure! Kindly, it was not their Latin names…

This old chestnut came up again (ha ha, but really, what’s that saying mean?): MADCap Horse, a mnemonic for common trees & shrubs with opposite leaves. It stands for Maple,Ash,Dogwood,Cap (the honeysuckle family) and Horse chestnut or buckeye. For example, Catalpa,Horsechesnut, and Buckeye have opposite or whorled leaves. Rhamnus cathatica (common buckthorn) has an uncommon arrangement-sub opposite (not quite opposite but close).

OAK
We saw white oaks and red oaks (which confusingly includes the black oak (Quercus velutina). In general, you can spot an oak in winter because it holds some of it’s leaves. All oaks have multiple terminal buds. Their bark is less furrowed ( I forgot to note “than what”, but I assume maple!), and the furrows run a longer distance before a cross break. Heavy acorn drop varies from year to year. the timing of the cycles is not predictable, but the advantage seems obvious-keeping the populations of mast-consumers in check. Oaks in a given area will produce heavily or lightly in unison, but it is not known how this is coordinated. There was some speculation in the group about mycorrhizal communication between trees, one of your more awe inspiring and humbling concepts.

White oak bench.

Quercus palustris (Pin oak): Native, but at the edge of it’s range. It’s limbs go straight up. Leaf sinuses are deeper than red oak.

Looking for Quercus rubra

Quercus rubra (Red oak):Acorns take two years to mature, so the first year they are small.

Quercus alba (White oak): Acorns mature in a year. The bark is paler than other oaks, and forms shingles higher up.

Quercus rubra (Red oak)

Quercus alba (White oak)

Quercus velutina (Black oak)

Quercus velutina (Black oak):The leaves are tough,leathery,deeply sinused, pointy and have bristles. The bark is rough.

Hickories
Unlike the black walnut (Juglans nigra), other members of the family are not toxic to the plants around them.

Carya ovata (Shagbark hickory)

Carya ovata (shagbark): The bark has plates loose enough for bats to hibernate in.

Carya glabra (Pignut hickory)

Carya glabra (pignut): Bark is shaggy, but narrower and shorter than Shagbark.

Carya cordiformis (Bitternut hickory):The bark is the smoothest of the hickories, with orange in the recesses of the cracks.

Carya cordiformis (Bitternut hickory)

Salix nigra:

Our native willow is smaller than the common white willow (Salix alba) which, along with Salix fragilis, is displacing it. Its trunk is more crooked, and it’s leaves lost earlier. You can see it, and a white willow further down, from the bridge. I wish I could tell you which direction, or name the bridge, but it is that fun super bouncy one.

Salix nigra (Black willow)

Larix laricina (Tamarack): You might see the native species around here in bogs or fens-highly acidic, coolly wet sites, but it prefers more northern locations. Mostly you see Japanese larch, a decidious conifer commonly planted.

Tillia americana (Basswood): Our only native North American Linden. Though

Tilia americana (Basswood)

the bark can look like ash, it is not as consistent a diamond pattern. The leaves are large,heart shaped,and alternate. The buds are big, to hold the large leaves, and reddish. It often sprouts from the base, unlike ash, and can sound hollow when hit.
ASH
Fraxinus americana (white ash):The bark has regular diamond or canoe

Fraxinus americana (white ash)

shaped fissures. Leaves are pinnate (usually seven), opposite, with thick twigs. We had a hard time finding leaflets on the ground still attached to the petiole.

Fraxinus nigra (Black ash): A wetland tree new to me. The bark is distinctively corky. Leaves are pinnate,with 11-13 leaflets. The buds are fat compared to White ash.

Fraxinus nigra (Black ash)

Populus deltoides (cottonwood): Found in lakesides and river bottoms. Poplar have flat petioles, which causes the leaf to move in the breeze-think Quaking aspen.

Acer rubrum (red maple) bullseye

Maple
Acer rubrum: If you can’t tell which maple it is, it’s red. The bark may have a papery outer layer, is thinner & easier to break than Sugar maple, silvery gray where weathered. Sometimes there is a tell-tale bullseye pattern.The trunk may be fluted in old age. The buds are redder & rounder than Sugar maple.

Acer saccharum (Sugar maple): The bark plates do not break off easily. If cut, they show an orange-brown.

PINE
Pinus strobus (White pine): Has five needles and black-purple bark.

Pinus resinosa (Red pine):A native that prefers steep,dry,south slopes, as it’s roots are very sensitive to fungal attack. It has two needles and redder,flakier bark than White pine.

Pinus sylvestris (Scots pine)

Pinus sylvestris (Scots pine):The trunk is bald & orange higher up.

Prunus serotina (Black cherry):
Native,its dark, purplish bark is described in almost all the NAA workshops as “burnt potato chips”. The largest tree in the Plantations native plant area is a cherry, located across the street from where we walked. I’ll like to hunt that down someday!

Platanus occidentalis (Plane tree/Sycamore):
The bark is scruffy at the base, becoming mottled higher up as the bark flakes off.

Robinia pseudoacacia (black locust):
This legume is native as far as PA, but this far north it is introduced and naturalized. It usually has a crook in the trunk and doesn’t grow straight up. Leaves are pinnate, the bark pale tan, coarser and more irregular than ash.

Robinia pseudoacacia (Black locust)

Fagus grandifolia (American beech):
Its bark is smooth if not diseased (yet!). Holds it’s leaves in the winter.

Carpinus caroliniana (Musclewood):
It is a hard but not particularly decay resistant wood. The trunk has a sinewy look, with flexible branches.

Ostrya virginiana (hop hornbeam): Both understory trees, Musclewood is also sometimes called Hornbeam, and both are sometimes called Ironwood. So let’s just not, okay? Its bark is evenly shaggy in small strips

Ostrya virginiana (hop hornbeam)

Lindera benzoin (Spicebush):
One of our only two natives (along with Sassafras) in the Lauraceae family. Any part scratched is fragrant. The buds are small and round.The flowers cause it to appear as a yellow haze in the spring woods.

Ulmus americana (American elm):
The bark is corky & spongy like Black Ash. A piece broken off alternates dark & light bands in cross section.
Juniperus virginiana (Eastern red cedar):
Not a cedar, but a member of the Cyprss family. Native,but marginal here. More likely found near the lake than “the hills of South Danby”. Harsh!

Juniperus virginianana (Eastern red cedar)

Juniperus virginianana (Eastern red cedar)

Celtis occidentalis (Hackberry):
This is the northern edge of it’s range. Its bark is strange-corky & warty. The leaves are asymmetric at the base.

Celtis occidentalis (Hackberry)

Amelanchier laevis (Shadbush/Allegehny serviceberry):
Gets the biggest of the serviceberries. Smooth barked, often multistemmed.

Amelanchier laevis (Shadbush)

Viburnum acerifolium (Maple leaf viburnum):
Native,resistant to Viburnum beetle.

Crataegus (Hawthorn):
North America has lots of native species.

Liriodendron tulipifera (Tulip tree):
Like other Magnolias, suffers from fungus problems if too wet at the wrong time.

No woods walk is complete without an assortment of invasive species:
Ligustrum ovalifolium (Privit): Though called Californian privit, it is from Asia.
European barberry: Taller, with larger,toothed leaves than the Japanese barberry commonly seen in gardens. The Japanese version is even more invasive.

There you have it-enough trees in an hours walk to fill a blog!

Black cherry,sycamore,sugar maple