sapindaceae s.l. (aceraceae) - maple family acer...

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Sapindaceae s.l. (Aceraceae) - maple familyAcer saccharinumsilver maple

Vegetative Features:

• Leaf: 4-6" long, simple, opposite, deciduous, deeply,

palmately 5-lobed – light green above and silvery below.

• Twig: lustrous with small lenticels, buds usually blunt, leaf

scars V-shaped, 3 bundle scars unpleasant odor when

crushed; buds reddish brown, large scales, flower buds often

in conspicuous dense clusters.

• Bark: smooth and gray on young trees but develops

distinctive loosely attached scales on older trees. Often

distinctive vase-shape – forking/y-shaped trunk.

Reproductive Features:

• Polygamous (mixture of perfect and imperfect flowers) with

reduced perianth, emerging very early in the spring before the

leaves.

• Fruit a samaroid schizocarp, mericarp wings slightly divergent,

1 1/2 - 2 1/2" long.

Sight ID characteristics

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NOTES AND SKETCHES

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Sapindaceae s.l. (Aceraceae )- maple family Acer rubrumred maple


• Leaf: 2 1/2-4" long, simple, opposite, deciduous, palmately

3-5-lobed with serrate margins, sinuses at right angles, light

green above, pale and glaucous below.

• Twig: lustrous with small lenticels, buds usually blunt, green

or reddish (fall and winter) with several loose scales, leaf

scars V-shaped, 3 bundle scars.

• Bark: smooth and gray on young trees but breaks into scaly

plates on older trees.


• Polygamous with reduced perianth, emerging very early in

the spring before the leaves.

• Fruit a samaroid schizocarp, mericarp wings slightly

divergent approximately 3/4"

long.


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NOTES AND SKETCHES

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Sapindaceae s.l. (Aceraceae) - maple familyAcer saccharumsugar maple


• Leaf: 3 1/2-5 1/2" long, simple, opposite, deciduous,

palmately 5-lobed, margin entire or nearly so, sinuses acute

angles and rounded, apex acuminate, base cordate, bright

green above and pale below with both surfaces glabrous,

base of petiole red in spring.

• Twig: brown, slender and shiny with lighter lenticels; terminal

buds brown, very sharp pointed, with tight scales.

• Bark: gray and deeply furrowed on older trees.


• Polygamous, yellow, long pubescent pedicels, emerge with

the leaves.

• Fruit a samaroid schizocarp, mericarp wings 1-1 1/4" long and

parallel to slightly divergent.


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NOTES AND SKETCHES

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Sapindaceae s.l. (Aceraceae) - maple familyAcer negundobox-elder


• Leaf: opposite, deciduous, pinnately or ternately compound,

3-7 leaflets are short-petioled, variably toothed.

• Twig: green to purplish green, moderately stout, leaf scars

narrow, often glaucous; buds white and hairy.

• Bark: thin, gray to light brown, with shallow interlacing ridges.


• Dioecious, flowers, apetalous and yellow-green, emerging

with or before the leaves.

• Fruit a samaroid schizocarp, 1 1/2 inches long, in drooping

clusters, light tan in fall, persist throughout winter.


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NOTES AND SKETCHES

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Sapindaceae s.l. (Aceraceae) - maple familyAcer macropyhllumbigleaf maple


• Leaf: simple, opposite, deciduous, 6-10" long, palmately 5-

lobed, bright green above paler below, petioles with milky sap,

• Twig: stout, smooth, terminal bud large, with 3 or 4 greenish

red scales.

• Bark: light gray-brown and smooth on younger trees,

becomes furrowed on older trees.


• Polygamous, flowers are yellow-green, showy with perianth,

borne in puberulent racemes.

• Fruit a samaroid schizocarp, mericarp wings are 1-1 1/2" long

and densely pubescent.


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NOTES AND SKETCHES

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Sapindaceae s.l. (Aceraceae) - maple familyAcer glabrumrocky mountain maple


• Leaf: opposite, deciduous, variable, usually 3-5-lobed, but

often pinnately compound with 3 leaflets in the S. Rockies,

bright green above, whitish below.

• Twig: slender, pale green to red, buds red and pointed.

• Bark: thin, tight, smooth and gray.


• Polygamous, small yellow flowers, 4 sepals, 4 petals,

emerging with leaves.

• Fruit a samaroid schizocarp, mericarp wings moderately

divergent, 3/4-1" long.


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NOTES AND SKETCHES

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Sapindaceae s.l. (Aceraceae) - maple familyAcer platanoidesNorway maple


• Leaf: simple, opposite, deciduous, 4-7" long, 5-lobed with

acuminate apex with a very pinched sharp tip, acute angled

and rounded sinuses (similar to Acer saccharum, light green

above and paler below.

• Twig: stout, brown with a large, green to purple terminal bud,

large bud scales.

• Bark: dark gray-brown, tightly furrowed into narrow ridges on

mature trees.


• Usually dioecious, yellowish green flowers emerge before

leaves.

• Fruit a samaroid schizocarp, mericarps widely divergent, 1

1/2-2" long.


CULTIVATED

ornamental

escaped

naturalized

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NOTES AND SKETCHES

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Sapindaceae s.l. (Hippocastanaceae)Aesculus hippocastanumhorsechestnut


• Leaf: opposite, deciduous, palmately compound, 7 obovate

(occasionally 5) leaflets.

• Twig: stout, leaf scar large, shield-shaped; terminal bud large

(1/2 - 1”); shiny, sticky, reddish brown.

• Bark: gray-brown and loosely scaled on mature trees.


• Flowers showy and perfect, white with pink or yellow blotches

on petals. Arranged in erect panicles.

• Fruit is a large leathery and moderately spiny capsule that

contains a single hard brown, smooth seed

• Seed poisonous.


CULTIVATED

ornamental

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NOTES AND SKETCHES

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Simaroubaceae – tree-of-heaven familyAilanthus altissima

tree-of-heaven


• Leaf: alternate and deciduous, pinnately compound with

11-41 ovate-lanceolate leaflets, 1-2' long, leaflets 3-5" long

with 1-5 basal teeth with gland below.

• Twig: stout and pithy, very weak; large, shield shaped leaf

scars.

• Bark: gray-brown and smooth on young trees, becomes

fissured on older trees.


• Dioecious, flowers small and inconspicuous, yellowish in

terminal clusters.

• Fruits are twisted samaras with seed in the middle; borne in

terminal clusters and often remaining on the tree over winter.


CULTIVATED

escaped

naturalized

invasive

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NOTES AND SKETCHES

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Altingiaceae – sweet gum familyLiquidambar styraciflua

sweetgum


• Leaf: alternate, deciduous, palmately lobed, palmately veined,

star-shaped, margins finely serrate.

• Twig: shiny green to yellow-brown, often with corky

outgrowths, terminal bud large, sticky, bud scales shiny, green

to orange-brown.

• Bark: Gray-brown, irregular furrows.


• Monoecious, flowers imperfect, inconspicuous, arranged in

globose heads.

• Fruit a woody, 2-celled, beaked capsule arranged in globose

heads.


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NOTES AND SKETCHES

sapindaceae s.l. (aceraceae) - maple family acer...

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