Betulaceae (Birch Family)
6 Genera (4 on campus)
120 species
I. Leaves
A. Deciduous
B. Alternate
C. Simple
D. Stipulate
E. Double Serrate
II. Flowers
A. Monoecious
B. Axillary staminate aments
C. Axillary pistillate short spikelike aments
III. Fruits
A. Small to medium size winged/unwinged nut
subtended by
papery or semiwoody bract
IV. Economic importance
A. Ornamental
B. Veneer (doors, cabinets)
C. Furniture lumber
D. Fuel wood
E. Edible Filbert/Hazelnut (Corylus)
V. Range
A. North temperate latitudesGeneric comparison/
Species characteristics
I. Betula (Birch)
[Shining, in reference to bark]
A. Very small laterally winged nuts subtended by
three lobed bract
in compact ament
B. B. nigra
(River birch)
1. Deltoid leaves with white & pubescence underside
2. Horzontally elongated lenticels
3. Salmon-pink
bark curls into horizontal sheets
II. Alnus (Alder)
[Latin name]
A. Very small laterally winged nuts born on a woody
persistent conelike
ament
III. Carpinus (Hornbeam)
[Latin name, Celtic for a yoke made from this
wood]
A. Small unwinged nuts subtended by three lobed bract
in leafy spikelike
clusters
B. Carpinus caroliniana (American hornbeam, bluebeech,
musclewood, water
beech, ironwood)
1. Elliptical leaves
2. Pubescent, < 4mm long buds
3. Smooth, blue-grey,
fluted bark
IV. Ostrya (Hophornbeam)
[Greek = Shell, in reference to bladderlike
bracts]
A. Small unwinged nuts enclosed in bladderlike bracts
in elongated
clusters resembling hops infructescence
B. Ostrya virginiana
(Hophornbeam, ironwood)
1. Elliptical yellow-green leaves
2. Brown, vertical
platelike shredded bark
V. Corylus (Hazel nut)
[Latin name]
A. Large unwinged nuts subtended by foliaceous
bract
B. Corylus avellana
(Filbert, Hazel nut)
1. Oval to broadly elliptical leaves with capitate
hairs
2. Shrub
Salicaceae (Willow or Poplar Family)
[Latin for willow]
2 Genera
350 species (2,3 on campus)
I. Leaves
1. Deciduous
2. Alternate
3. Simple
4. Stipulate
5. Often with glands on petiole or lamina]
II. Flowers
1. Dioecious
2. Both male & female flowers born in aments
III. Fruits
1. 1 celled, 2- to 4- valved capsule containing
numerous tufted short lived moisture requiring
seeds
IV. Economic importance
1. Coppice growth -> erosion control
2. Fast growing, short lived ornamentals
3. Wood pulp for paper
4. Box, crate lumber
V. Range
1. Worldwide, but most abundant in cooler northern latitudes
and mountainous regions of tropics
Generic comparison / Species Characteristics
Salix (Willow)
[Latin for willow]
A. Lanceolate to elliptical leaves, sessile or with short
petiole
B. Persistant stipules
C. No terminal buds present because inflorescence in
terminal position
D. Lateral buds covered with single caplike
scale
E. V-shaped leaf scars
F. S. nigra (Black willow)
1. Slender, brittle, purplish-green to orange-brown
twigs
2. Reddish brown lateral buds
3. Brown to blackish bark subdivided into deep fissures
seperating interlacing scaly ridges
G. Common ornamental species
1. S. discolor (Pussy willow)
2. S. babylonica
(Weeping willow)
Populus (Aspens, Cottonwoods, Poplars)
[Latin for Poplar]
A. Ovate to deltoid leaves with long terete or
laterally compressed
petioles
B. Stipules not persistant
C. Terminal buds present with imbricate scales
1. Nonresinous in Aspens
2. Resinous in
Cottonwoods & Poplars
D. Deltoid to Elliptical leaf scars
E. Populus deltoides (Eastern cottonwood)
1. Deltate to ovate-deltate leaves with laterally
compressed petioles and glands along margin
2. Ashy gray bark subdivided into thick, broad, flattened
or rounded ridges seperated by deep furrows
F. Other common species important for pulp wood
1. P. tremuloides (Quaking Aspen)
a. Most widely distributed tree in USA
2. P. grandidentata
(Big Tooth Aspen)
Annonaceae (Custard-Apple Family)
130 Genera
2300 species
I. Leaves
A. Simple
B. Alternate
C. Estipulate
D. Entire
E. Aromatic
II. Flowers
A. Solitary
B. Perfect
C. Regular
D. 6-9 tepals
E. numerous stamens
F. 3-celled pistil
IV. Fruit
A. Berry with large seeds
V. Economic Importance
A. Edible Fruit
1. Custard Apple
(Annona reticulata)
2. Cherimoya
(Annona cherimoya)
3. Soursop (Annona
muricata)
4. Pawpaw (Asimina
triloba)
VI. Range
A. Tropics
VII. Asimina triloba (Pawpaw)
[Native American name-G, three lobed-se]
A. Small understory tree
B. Obovate, foul smelling leaves
C. Dark maroon flower
Aquifoliaceae (Holly Family)
4 Genera
420 species
I. Leaves
A. Mostly evergreen
B. Alternate
C. Simple
D. Stipulate
II. Flowers
A. Imperfect (dioecious)
B. 5-merous
III. Fruit
A. Drupe
IV. Economic Importance
A. Ornamentals
B. Christmas decorations
C. Furniture wood
V. Range
A. Worldwide
VI. Ilex opaca (American Holly)
[Ancient L name for oak-G, opaque-se]
A. Spiny teeth (aculeate)
B. Greenish-white flowers
C. Poisonous red fruit
D. Light gray, warty bark
Rhamnaceae (Buckthorn Family)
53 Genera
900 species
I. Leaves
A. Simple
B. Stipulate
C. Alternate or subopposite
II. Flowers
A. Perfect or imperfect (polygamous)
B. 5-merous
C. 2-, 3-celled pistil
III. Fruit
A. Drupe, capsule
IV. Economic Importance
A. Roots, bark, stems, leaves contain useful
compounds for
pharmaceuticals
B. Edible jujube (Ziziphus jujuba) from Asia
V. Range
A. Tropics & warmer latitudes
VI. Rhamnus cathartica (European Buckthorn)
[Ancient Grk name for prickly shrubs-G,
purgative-se]
A. Purplish black drupe
B. Spine tipped branches