Transcript ANGIOSPERM FAMILIES 02

ANGIOSPERM FAMILIES 02
JUGLANDACEAE
THE WALNUT FAMILY
JUGLANDACEAE
THE WALNUT FAMILY
• Trees or large shrubs.
• Forests of the North Temperate zone and to
some extent in the tropics of both
hemispheres.
• 9 genera and about 60 species worldwide.
• Two genera and 17 species in N America.
– Juglans
– Carya
CHARACTERISTICS OF THE FAMILY
• HABIT: trees and large shrubs.
• LEAVES: deciduous, alternate, pinnately
compound, estipulate.
• FRUIT: a hard nut surrounded by woody or
semifleshy husk; husk dehiscent or
indehiscent; seed with large convoluted
cotyledons.
DETAILS OF THE FLOWER
• Anemophilous.
• Unisexual, monoecious.
• Calyx lobed, 3-5 lobes; subtended by a bract
and two bracteoles.
• Petals absent.
• Staminate flowers in catkins.
• Pistillate flowers solitary or few in stalks.
JUGLANS FEMALE FLOWERS
JUGLAND NIGRA L.
JUGLANS CINEREA L.
JUGLANS MALE FLOWERS
JUGLANS NIGRA L.
JUGANS CINEREA L.
GENUS JUGLANS
• LEAVES: pinnate, odd or even pinna number;
leaflets 9-23, sessile or nearly so, oblonglanceolate, apex acute or acuminate, uneven
base, margin finely serrate, apical leaflet often
absent; petiole and rachis stout and finely
pubescent.
• FLOWER: plant monoecious; imperfect; male
flowers in catkins; female flower solitary or in
short spikes, with plumose stigmas.
GENUS JUGLANS cont.
• FRUIT: a nut with semifleshy indehiscent husk;
nut thick-walled, corrugated; seed sweet often
oily.
• TWIGS: light brown, stout, pubescent or
glabrous; pith chambered; terminal bud with
few scales.
• LEAF SCARS: 3-lobed, with three U-shaped
bundle scars.
JUGLANS NIGRA L.
Black walnut
JUGLANS CINEREA L.
Butternut or White walnut
FRUIT COMPARISON
JUGLANS NIGRA L.
JUGLANS CINEREA L.
GENUS JUGLANS
Range in North America
Juglans nigra L.
Juglans cinerea L.
GENUS CARYA Nutt.
HICKORIES
• Trees
• Present range: Eastern North America,
southern Canada and Mexico; Caucasus to
Japan.
• Extinct range: Europe, N Africa, Asia, and N
America.
• 18 extant species; several extinct species.
CHARACTERISTICS OF THE GENUS
• LEAVES: pinnately compound; 3 -17 sessile or
nearly so leaflets, apical leaflet usually the
largest; leaflets ovate to obovate, apex acute
or acuminate, uneven bases, margin finely
serrate, pubescent; petiole and rachis
pubescent or glabrous, stout.
• FLOWERS: plant monoecious, flowers
imperfect; staminate flowers in 3-branched
catkins, 3 to 7 stamens, 2-3 lobed calyx;
CHARACTERISTICS OF THE GENUS
• FLOWERS cont.: pistillate flowers on 2 to 10
terminal spikes, ovary 1-celled with two
stigmas, subtended by a bract and three
bracteoles.
• FRUIT: ovoid, pyriform or globose nut encased
in a woody husk that may split in four sutures;
seed with a thick or thin shell.
• TWIG: stout or slender, dark brown, gray or
orange brown; terminal bud large
CHARACTERISTICS OF THE GENUS
• SCARS: 3-lobed or deltoid; many bundle scars
in 3 U-shaped clusters.
• PITH: homogeneous
• NORTH AMERICAN HICKORIES are grouped in
two sections:
– Section Carya, true hickories
– Section Apocarya, pecan hickories
INFRAGENERIC CLASSIFICATION
• SECTION Carya, true hickories
– Leaflets 5 – 7, terminal leaflet the largest.
– Fruit unwinged, with sutures occasionally ribbed.
– Bud scales imbricate; 6 – 9 thin scales
• SECTION Apocarya, pecan hickories
– Leaflets 7 – 13, leaflets similar.
– Fruit broadly winged at the sutures.
– Bud scales not overlapping; 4 – 6 fleshy scales.
CARYA TOMENTOSA (Poir.) Nutt
Mockernut hickory.
LEAF
FRUITS
CARYA TOMENTOSA (Poir.) Nutt.
CARYA GLABRA (Mill.) Sweet
PIGNUT HICKORY
LEAF
FRUIT
CARYA GLABRA (Mill.) Sweet
PIGNUT HICKORY
TWIG
LEAF UNDERSIDE
CARYA ILLINOIENSIS (Wangen.) K. Koch
PECAN
CARYA ILLINOIENSIS (Wangen.) K. Koch
PECAN
ECONOMIC IMPORTANCE OF THE
JUGLANDACEAE
• The walnuts produce a valuable wood used in
cabinetry.
• Hickories produce a very strong wood used for
many purposes where strength is needed.
• Pecan is the most valuable nut in N America.
• The nuts of walnuts and hickories are an
important source of food for wildlife.
• Important ornamental trees.