Four Season Virtual Tree Trail

Dichotomous Tree Key

 

The dichotomous tree key is a tool to identify the station trees by looking at specific identification traits and then making a choice between two options.

This first section of the key is for spring, summer and fall.  Click here to skip to the winter dichotomous tree key.  Clicking on any terms shown in blue will take you to the illustrated glossary.

 

Tree Key for Spring, Summer and Fall

 

1A. Does the tree bear small fleshy soft CONES and do the leaves hug the twig and are SCALE-like?  

CLUE: These trees are called CONIFERS and most are EVERGREEN.

Are the needle-like LEAVES  dark green and cones (if present) pale, berry-like and AROMATIC when crushed?  

Eastern Redcedar, Juniperous virginianus

 

1B. Does the tree have leaves that are flat, somewhat broad, thin, and generally shed annually? 

CLUE: These trees are called broadleaf and most are DECIDUOUS and bear a variety of FRUIT and FLOWERS GO TO 2.

 

 

2A. Are leaves SIMPLE (One BLADE attached to a stalk or PETIOLE)?   GO TO 3.

 

2B. Are the leaves COMPOUND (more than 1 BLADE attached to a single stalk or PETIOLE)?  GO TO 9

 

 

3A. Are the leaves CHORDATE (heart shaped) with PALMATE veins and broad as they are long?                                                                                                            

Eastern Redbud, Cercis canadensis

                                                                                                                                   

3B. Are the leaves not as above (heart-shaped)?  GO TO 4.

 

 

4A. Do the twigs have obvious corky wings and are leaf veins PINNATE in a CHEVRON pattern and is leaf rough below with a DOUBLY SERRATE  MARGIN, and ASYMMETRIC base?                                                                                   

 

Winged Elm, Ulmus alata

                                                                                                                                   

 4B. Are the leaves and bark not as above?  GO TO 5.

 

 

5A. Are the leaves 4-6 inches long with pointed tips, waxy, glossy upper surface, and pale green below?  Are they 2-3 inches wide with smooth MARGINS and a broad flat MIDRIBIs bark dark and deeply grooved into thick square plates?

 

Persimmon, Diospyros virginiana

                                                                                                                                     

 5B. Are the leaves and bark not as above?  GO TO 6.

 

 

6A. Are the leaves yellow-green, 15 cm long with 11-15 pairs of PINNATE veins in a CHEVRON pattern?  Are MARGINS DOUBLY SERRATE?  (Undersides are often hairy)

 

Eastern Hophornbeam, Ostrya virginiana

                                                                                               

6B. Are the leaves not as above.  GO TO 7.

 

 

7A. Are the leaves PALMATE with broad-toothed edges and have 3-4 lobes separated by broad shallow SINUSES?  (This tree has bark high on the tree that is peeling in an irregular pattern revealing light-colored underbark.)     

                                                                                                                                                    

American Sycamore, Platanus occidentalis

                                                                                                                                   

 7B. Are the leaves and bark not as above?  GO TO 8.

 

 

8A. Are the leaves SIMPLE, oblong-lanceolate (oblong with both ends somewhat pointed), 4-6 inches long, bright green above, pale and PUBESCENT below, broadly toothed along margin with large GLAND-tipped teeth. 

 

Chinquapin Oak, Quercus muehlenbergii

 

Are the leaves and bark not as above?  GO TO 8B.

 

8B. Are leaves SIMPLE, do they resemble a Turkey foot in shape, 5-9 inches long, dark green and smooth above, pale yellow or gray and PUBESCENT below, with 3-7 lobes and SINUSES almost to the MIDRIB, base of leaf "U" shaped.

 

Southern Red Oak, Quercus falcata

 

Are the leaves and bark not as above?  GO TO 9.

 

9A. Are the leaves PINNATELY COMPOUND and OPPOSITE to each other?  GO TO 10.

 

9B. Are the leaves PINNATELY COMPOUND and ALTERNATE on the twig?  GO TO 11.

  

10A. Are the dark green leaves 8-12 inches long with 5-9 (usually 7) leaflets that are 3-5 inches long?  Are their MARGINS ENTIRE or finely TOOTHED with forward teeth and prominent veins?  The undersides of the leaves are often PUBESCENTSAMARAS are pointed at the tip, and the seeds are only partially enclosed by the wings.                                                        

 

White Ash, Fraxinus americana

                                                                                               

10B. Are there 5-11 SERRATE LEAFLETS (typically 9) each with an OBLIQUE base and found on a slender RACHISSAMARAS if present are boat-paddle shaped with blunt tips.  Seed is completely enclosed by the wing.

 

Blue Ash, Fraxinus Quadrangulata

                                                                                                           

11 A & B.  These leaves should be PINNATELY COMPOUND, each with a TERMINAL LEAFLET.  Leaves ALTERNATE along the twig.  Leaflets are TOOTHED, oval in shape with pointed tips and may be AROMATIC when crushed.

 

11 A. Are the LEAFLETS in 5s on stout RACHIS, 4 cm PETIOLE, and DOWNY on the underside?  Each leaf has a TERMINAL LEAFLET and the bark flakes in long curling plates?                                                                        

 

Shagbark Hickory, Carya ovata

 

11B. Do the leaves have 7, 9, or 11 LEAFLETS and turn yellow in autumn?  Bark not shaggy as above, but slate gray to light gray, relatively smooth with tight interlacing ridges.

 

Bitternut Hickory, Carya cordiformis

                                                                                                                                     

 

Tree Key for Winter

1A. Does the tree bear small fleshy soft CONES  and the leaves hug the twig and are SCALE-like? 

CLUE: these trees are called CONIFERS and most are EVERGREEN

Are the needle-like leaves dark green and cones (if present?) pale, berry like  and AROMATIC when crushed?

 

Eastern Redcedar, Juniperous virginianus

 

1B.  Does the tree have leaves that are flat, somewhat broad, thin, and generally shed annually?         

CLUE: These trees are called broadleaf and most are DECIDUOUS and bear a variety of FRUIT and FLOWERS GO TO 2.

 

 

2A. Are the BUDS OPPOSITE each other?  GO TO 3.

 

2B. Are the buds not as above?  GO TO 4.

 

 

3A.  Are the BUDS OBTUSE (rounded), broadly OVATE, 2 KEELED, ACUTE, HAIRY, black in winter with stout SHOOTS that are often GLABROUS after blooming season.  If present are the SEEDS lance-shaped SAMARAS with pointed tips?  Do the wings only partially enclose the seed?

 

White Ash, Fraxinus americana

 

3B. Are the twigs 4-angled (square) with 4 corky narrow wings, becoming round in the 3rd season with buds that are rounded, 6 mm, and slightly hairy?   Is bark gray with a diamond like pattern?  If present, are seeds boat paddle-shaped SAMARAS with blunt tips?  Does the wing completely enclose the seed?

 

Blue Ash, Fraxinus Quadrangulata

 

                                                                                                                                   

 4A.   Does the bark flake in long curling plates?   Are TERMINAL BUDS brown with 5-8 loose-fitting scales and 19-25mm long, LATERAL BUDS 13mm long?  Are BU D SCALES IMBRICATE (overlapping)?           

 

Shagbark Hickory, Carya ovata

 

4B. Is the bark not as above?   Are winter buds bright sulphur yellow, VALVATE, TERMINAL BUD 13mm long, LATERAL BUDS 6mm long?                                                 

 

Bitternut Hickory, Carya cordiformis

 

 

5A. Is the bark EXFOLIATING at the top of the tree in random paper thin patches revealing light colored patches of underbark?  Do twigs resemble a zig zag?       

 

American Sycamore, Platanus occidentalis

                                                                                                                                  

 5B. Are the bark and twigs not as above?  GO TO 6.

 

 

6A. Are the shoots slender, hairy in their first year and often with thick corky wings after 3-4 years?                                                                                   

 

Winged Elm, Ulmus alata

                                                                                                                                   

 6B. Are the shoots and twigs not as above?  GO TO 7.

 

 

7A. Are the small  dark alternate buds flattened in shape and APPRESSED?  Terminal buds lacking?  Are twigs zig-zag, slender, GLABROUS gray to reddish brown with orange LENTICELS?  Older bark is dark grey/black and cracked into squares?

 

Persimmon, Diospyros virginiana

                                                                                                                                   

 7B. Are the buds and bark not as above?  GO TO 8. 

 

 

8A.  Is the bark reddish-brown and broken into narrow APPRESSED  plates that are shaggy at their ends like Eastern Redcedar bark?   Are young shoots light green and hairy?   Are buds 6mm long, ACUTE, bud scales finely striated with brown edges that contrast with light green centers?  Are leaves PERSISTENT in winter?

 

Eastern Hophornbeam, Ostrya virginiana

 

 8B. Are the bark, shoots, and buds not as above?  GO TO 9.

 

 

9A. Are the twigs slender with a zig zag pattern and no TERMINAL BUD, while LATERAL BUDS are small, dark, APPRESSED and often SUPERPOSED?

 

Eastern Redbud, Cercis canadensis

                                                                                                                                   

 9B. Are the twigs not as above?  Do the twigs have clusters of buds at the tips?

 

 

10A.  Is the bark light gray and thin with shallow fissures, forming irregular squarish scales?

 

Chinquapin Oak, Quercus muehlenbergii

 

11B.  Is the bark dark gray or blackish, divided by shallow fissures into ridges?  Is underbark visible in fissures orange?

 

Southern Red Oak, Quercus falcata

 

 

   
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