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Posts tagged “Tree Identification

Black Walnut – Identification in Winter

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Black walnut (Juglans nigra) is a relatively easy tree to identify, as it has so many distinctive qualities. In the summer there are round, tennis-ball-sized nuts, which have a delightful smell.  The bark of black walnut is dark and deeply furrowed.  Best of all are the twigs and buds.  If you cut a twig at an angle, you will see the central portion, or pith, is chambered.  It is also brown.  The only other tree that is chambered (not solid) like this is its relative, butternut (Juglans  cinerea), and butternut’s pith is buff colored.  The buds of black walnut are greyish and fuzzy – lacking bud scales.  By far the most amusing thing about black walnut (and butternut) is its leaf scars – the scar left when a leaf falls off.  The vessels that transport food and water, called vascular bundles, are darker than the rest of the scar, and are shaped in such a way that the leaf scar resembles nothing more than the smiling face of a monkey!  (Butternut leaf scars also look like monkeys, but they have a “furrowed brow” of fuzz on the top edge of the leaf scar.)

 


Yellow Birch (Betula alleghaniensis)

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Yellow birch (Betula alleghaniensis) buds are oval and pointed, and there are two shades of brown on each of their 3 – 5 bud scales.  The buds and twigs of yellow birch taste like wintergreen.  In the early morning and late afternoon, look for ruffed grouse filling their crops (“budding”) in yellow birch trees, as these buds are one of their favorite foods.  The thin bark of a mature yellow birch is a very distinctive yellow-bronze color (the bark of saplings is a shiny red-brown color), and curls when it separates from the trunk.


Sugar Maple Buds & Bark

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Maples have what is referred to as “opposite” branching – the buds, leaves and branches are positioned opposite one another. If you look at this photo of the terminal bud of a sugar maple (Acer saccharum) you’ll see that the two lateral buds (on either side of the terminal bud) are directly across from each other.  This is relatively rare in the woody plant world — you’ve narrowed down the identity of a tree significantly if you determine that it has opposite branching (ashes and dogwoods, among others, share this characteristic). The buds of sugar maple are pointed.  The appearance of its bark depends on the age of the tree you’re looking at.  Saplings and younger branches are quite smooth (right branch in photo), whereas the bark of an old sugar maple is furrowed with vertical ridges curled outward along one side (left side of photo).


Northern Red Oak Identification in Winter

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While identifying an oak species by the shape of its leaf is fairly easy, there are other characteristics in winter, when leaves aren’t available (except under the snow), that serve as clues to an oak’s identity.  A mature northern red oak can be readily recognized by its bark — its ridges appear to have shiny stripes down the center.  The buds of northern red oak are also distinctive.  Like most oaks, red oak’s terminal (located at tip of twigs) buds occur in clusters.  Northern red oak’s terminal buds are conical, and are a reddish-brown color.


Tree Buds: American Basswood

Bark, silhouettes and buds are the three keys to identifying trees in winter. My preference is buds, as they are so distinctly different from one species to the next. American basswood, or linden (Tilia americana), is a favorite. Its plump, oval, asymmetrical red buds, bearing only one or two bud scales are unmistakable.


Tree Fruit and Seed Identification

One nice thing about having the ground covered with snow in October and November is that there is an additional tool available for tree identification.  Like all flowering plants, trees have fruits which contain seeds.  The fruits of many trees fall to the ground this time of year.  They are very helpful identification tools, especially when they are so obvious against the white snow.  In the photograph, there are fruits from five different trees:  starting at the top and going clockwise is the fruit of the sugar maple (Acer saccharum), referred to as paired samaras by botanists.  Each of the two seeds contains a papery wing that aids in dispersal.  Next is the fruit of the white ash (Fraxinus  americana), which has winged seeds borne in clusters.  Eastern hophornbeam’s  (Ostrya virginiana)  fruit is a cluster of papery bladders, which usually separate upon dispersal.  Each bladder contains a seed.  Along the bottom is the fruit of American basswood or linden (Tilia americana) ; several round seeds are borne on a stalk which is attached to a single modified leaf.  The last two clusters are the fruit of yellow birch (Betula alleghaniensis). They consist of structures that look like little bird feet (of which there are several in the photograph) that contain individual, tiny winged seeds (scattered throughout the photograph).