Lab - Plant ID List | Reverse Flashcards
Habit: Tree
Leaves: Alternate; pinnately compound, 12-25 leaflets, *with ‘lip’ at base of leaflet; *rank odor when crushed
Bark: Stretched-looking, smooth
Twigs and Stems: *Stout, straw color; *rank odor when broken; *large light brown pith. Terminal bud absent; *lateral buds small, with 2 opposite scales in a semi-blobose form.
Ailanthus altissima
Tree of Heaven
Simaroubaceae
Habit: Tree, sometimes shrubby
Leaves: Alternate, *bipinnately compound, to almost 2’ long. Leaflets tiny (1/4” - 1/2”) falcate and ciliate. Leaflets fold up at night and when bruised. Main vein on the ultimate leaflets is off center.
Twigs and Stems: Greenish, glabrous, with zigzag growth pattern, prominent lenticels, no terminal bud. Three bundle scars in leaf scar. Buds hidden under swollen petioles; buds glabrous.
Flowers: Resemble pink powder puffs due to the many showy stamens.
Fruit: Tan, broad, flat legume 5’ - 7’ long, with flattened dark brown seeds. Seeds have a terminal hilum (scar that marks the point of attachment). Rattles when shaken.
Albizia julibrissin
mimosa or silk tree
Fabaceae
Habit: Vine
Leaves: Alternate, grape-like but with more lobing, highly variable, deciduous. Typically with three lobes, but lobes are not always obvious. With tendrils or inflorescences opposite the leaves. Tendrils have no adhesive disks.
Flowers: Panicles of small white flowers in spring.
Fruits: *1/4”-1/3” colored fruits go from green, to yellow, to lilac, to purple, to porcelain blue as they ripen. With brown dots at all stages. Often all colors are present in same cluster.
Twigs and Stems: Angled stems, pubescent when young. Long internodes, nodes bulge where leaves connect. Surface of older stems cracks when you bend them (otherwise similar looking grapes do not do this).
Ampelopsis brevipedunculata
porcelain berry
Vitaceae
(now Ampelopsis glandulosa var. brevipedunculata)
Habit: Vine
Leaves: Opposite, to 15” long, pinnately compound, 9 - 11 leaflets; pubescent on veins on leaf back.
Twigs and Stems: Climbs by aerial rootlets; *straw-colored after leaf fall; leaf scars connected by transverse pubescent line. Leaf scar crater like. Small, tan buds are angled away from stem. Stem with prominent lenticels. Black color around leaf scars.
Flowers: *Trumpet shaped orange and scarlet flowers to 4” long. Blooms in summer.
Fruit: Brown capsule when mature; 4 - 6” long.
Campsis radicans
trumpetcreeper, trumpet vine
Bignoniaceae
Habit: Shrub
Leaves: Alternative, simple
Twigs and Stems: Twigs green or olive-brown, prominent lenticels.
Buds: alternate, superposed, and collateral arrangement, leaf scars crescent-shaped, bundle scars 3 or united. All parts of the plant are aromatic. New growth of stem is bright green.
Flowers: Greenish-yellow in axillary cluster. Midvein is yellow-green
Fruits: Red drupe
Lindera benzoin
spicebush
Lauraceae
Habit: Tree
Leaves: *Star-shaped; alternate, simple with glands at base of petiole.
Twigs and Stems: *Stout twigs may develop corky ridges; terminal buds large and shiny. Buds look sticky but they are not.
Fruits: Aggregate of spiny capsules in a ball.
Liquidambar styraciflua
sweetgum
Altingiaceae (Hamamelidaceae)
Habit: Tree
Leaves: Alternate, simple, lobed. Leaf hanging from petiole has outline of a mushroom, a tulip, or an old rotary telephone.
Twigs and Stems: Stipular scars surround stem. Many leaf scars crowded on twigs and stems. Valvate terminal buds, 1/2” long. Pith chambered.
Flowers: Large fleshy yellow and green flowers with many stamens in late spring. Typically they are high in the tree and you see them when they fall to the ground.
Fruits: Aggregate of samaras.
Liriodendron tulipifera
tulip poplar
Magnoliaceae
Habit: *Vine, climbing by tendrils. Has looser growth habit than Parthenocissus tricuspidata due to longer internodes and tendrils.
Leaves: *Alternate, palmately compound with 5 leaflets 3” - 4” long. New growth with red pigment. Petiole yellow-green with pinkish base.
Stems: *Disc-tipped tendrils provide support. Tendrils usually branched and >2” long. Adhesive discs on tendrils are oblong in outline and smaller than those in P. tricuspidata. Discs develop only when substrate requires it.
Parthenocissus quinquefolia
Virginia creeper
Vitaceae
Habit: Tree
Leaves: *Opposite, simple, 5” to 10” long and wide cordate bases and acuminate tips; *dark green and sparsely pubescent above, tomentose beneath.
Twigs and Stems: Stout, pith chambered (Catalpa is continuous). *Flower buds formed by late summer - visible as a branched panicle.
Flowers: Light lavender tubular flowers bloom before leaves emerge in the spring.
Fruits: Capsules persist through the winter.
Paulownia tomentosa
empress tree
Paulowniaceae
Habit: Low, irregular, spreading shrub.
Leaves: Alternate, glossy, trifoliate, *leaflet margins coarsely dentate/crenate. Glossy. lower surface pubescent becoming glabrous, petiole 1 to 1.5” long, fragrant when crushed.
Twigs and Stems: Slender, pubescent, aromatically fragrant when bruised, leaf scars circular and distinctly raised.
Fruits: Red to orange-red, hairy drupe. ¼” in diameter, borne in August-September and may persist into winter
Rhus aromatica ‘Gro-Low’
Gro-Low fragrant sumac
Anacardiaceae
Habit: Shrub
Leaves: Alternate, odd-pinnately compound (9 to 23 leaflets), *leaflet margins entire or nearly so; *rachis winged.
Twigs and Stems: Raised wart-like lenticels; U-shaped leaf scars; sap milky.
Fruits: Drooping panicles of pubescent crimson drupes.
Rhus copallina
C: dwarf sumac or winged sumac
F: Anacardiaceae
Habit: Shrub
Leaves: Alternate, odd-pinnately compound (11-31 leaflets); leaflets with serrate margins, *rachis winged.
Twigs and Stems: Velvety pubescence and raised wart-like lenticels; U-shaped leaf scars; sap milky. Pith orange-brown.
Fruits: Panicles of pubescent, crimson drupes. Not sticky.
Rhus typhina
staghorn sumac
Anacardiaceae
Habit: *Vine, climbing by aerial rootlets. May also grow as a shrub.
Leaves: *Trifoliolate, glossy leaves. *Usually only outer side of lateral leaflets shows a coarse serration. *Center leaflet with a 1”- 2” petiolule; lateral leaflets almost sessile.
Stems: *Uses aerial rootlets for climbing. Rootlets at internodes and nodes give old stems dark brown hairy appearance.
Toxicodendron radicans
poison ivy
Anacardiaceae
Habit: Dense, rounded, multi-stemmed shrub.
Leaves: *Opposite, simple, glossy above. Cuneate (wedge-shaped) leaf base.
Twigs and Stems: *Twigs (current year’s growth) red. Older stems with exfoliating (peeling) bark. *Fine twiggy growth approaching a fishbone pattern. Stems somewhat angular.
Flowers: Light pink flowers on current year’s growth. Flowers sterile (produce no fruit). *Pinkish sepals remain on plant through most of fall and winter.
Duration: Semi-evergreen to evergreen in this area.
Abelia ×grandiflora
glossy abelia
Caprifoliaceae
(now Linnaea xgrandiflora)
Habit: Shrub
Leaves: Alternate, simple, glabrous above, glaucous below.
Twigs and Stems: Zigzag, *with single spine at node, spur shoots common, *wood under bark is yellow; current year’s twig is dark reddish-brown.
Fruits: *Elongate, bright red berry, persists through early winter
Berberis thunbergii
Japanese barberry
Berberidaceae
Habit: Low Shrub. 2’ tall x 3’ wide.
Leaves: Alternate, simple, obovate. Narrow at base into a petiole. Margin entire. Solid reddish-purple above, green beneath, ½ to 1 inches long. Color is strongest in full sun. Does not show the lacy pink patches in the foliage of ‘Rose Glow’
Twigs and Stems: Zigzag, *with single ½” long spine at node, spur shoots common, *wood under bark is yellow; current year’s twig is dark red above, green beneath. Bark on older wood is grey with darker fishnet-pattern.
Fruit: *Bright red elongated berry, persists through early winter.
Notes: Possibly the most popular of the many barberries in cultivation.
Berberis thunbergii var. atropurpurea ‘Crimson Pygmy’
Crimson Pygmy barberry
Berberidaceae
Habit: Single or multi-stemmed tree
Leaves: Alternate, simple; *rhombic-ovate (diamond-shaped); doubly serrate margin except at base where it is entire; base wedge shaped; glaucous and pubescent beneath with prominent veins.
Twigs and Stems: Initially pubescent stem, later glabrous, with warty excrescences, usually two or three catkins at end of twig. *Stems over 2” diameter have light reddish brown, to salmon, to cinnamon brown exfoliating bark; old bark brown with ridges and furrows.
Flowers: Flowers in pendant catkins.
Betula nigra
river birch
Betulaceae
Habit: Tree
Leaves: *Whorled, 6” - 12” long, ovate to ovate-oblong leaves, entire margins, heavily pubescent beneath. Leaves scentless when crushed. Leaf apex long acuminate. Compare with Catalpa bignonioides that has abruptly acuminate leaf apices and leaves that have a bad odor when crushed. Whorled leaf scars (three at a node).
Fruit: Pod-like, 8” - 20” long capsule persists through winter. C. bignonioides pod is straight.
Twigs and Stems: Twigs and stems stout. Leaf scars ternate, round to elliptical, center depressed with ring of bundle scars. Pith solid, white. Twig is very dark greenish, with large light tan lenticels. Compare with brown twig of C. bignonioides.
Catalpa speciosa
northern catalpa
Bignoniaceae
Habit: Shrub to small tree
Leaves: Sub-opposite, simple, sessile.
Flowers: White, red, pink, lavender; terminal panicles 6-8” long. Blooms mid-July to frost. Fruit: Capsule, 1/2” long, persists after senescence.
Twigs and Stems: *Twigs grooved, square on new growth. *Bark exfoliating in plates, stems various shades of tan. Stipular mark on stem from one node to the next
Lagerstroemia indica
crapemyrtle
Lythraceae
Habit: Tree
Similar to base species of crepemyrtle but trunk develops *cinnamon color when stem reaches about 1.5 inches diameter.
Flowers: White
Lagerstroemia × ‘Natchez’
Natchez crapemyrtle
Lythraceae
Habit: Tree
Leaves: Alternate, with spicy fragrance when crushed; smooth (or shiny) green above, glaucous below. Semi-evergreen to fully evergreen.
Twigs and Stems: *Green, note stipule scars encircling nodes. Older stems are dark grey, there may be patches of green scattered in the grey. Buds are not fuzzy.
Fruit: Cone-like, rust-colored aggregate of follicles with red seeds. Aggregate fruit - a fruit formed by fusion of distinct pistils from within a single flower. Follicle - dry, dehiscent fruit formed by a single pistil and opening along one suture.
Magnolia virginiana
sweetbay
Magnoliaceae
Habit: *Vine, climbing by tendrils. Has tighter growth than Parthenocissus quinquefolia due to shorter internodes and tendrils.
Leaves: *Alternate, simple, polymorphic (many shapes); juvenile leaves are *trifoliate, adult leaves are entire or three-lobed.
Stems: *Disc-tipped tendrils provide support. Tendrils are pinkish, usually branched and <2”long. Adhesive discs on tendrils are circular in outline
Parthenocissus tricuspidata
Boston ivy
Vitaceae
Habit: Tree
Leaves: *Leaves and all parts aromatic. *Leaves highly variable: right mitten, left mitten, two lobed, and entire on the same plant. Used to make sassafras tea and root beer.
Twigs and Stems: Smooth, green with blotches of black and beige for several years, red when exposed to light. Sympodial habit of branching (growth from lateral buds surpasses the terminal bud - yields a graceful candelabra appearance especially in winter). Axillary bud small and slightly off center of leaf scar.
Fruits: Blue drupe on a bright red pedicel. Pedicels persist after fruit has dropped.
Sassafras albidum
sassafras
Lauraceae
Habit: Shrub
Leaves: Opposite, simple, *coarsely dentate. Typically roundish in outline but can be elongate. Typically glabrous above and below.
Twigs and Stems: Grayish; leaf scars with ciliate hairs at margins. Buds reddish-brown, imbricate (scales overlapping one another), lower bud scale forms a V-shaped notch.
Flowers: Lacecap type inflorescence.
Fruits: Dark blue-black drupes, borne in corymbs.
Viburnum dentatum
arrowwood viburnum
Adoxaceae
Habit: Shrub
Leaves: Opposite, *hairy on both surfaces. Veins are indented on the top surface and raised on the lower leaf surface. Leaves somewhat rounded in outline with an acuminate apex.
Twigs and Stems: Tan, *prominent lenticels (orange); recent growth tomentose. New rapidly growing twigs have orange tan bark with white lenticels.
Flowers: Inflorescence a corymb.
Fruits: Bright red berry, persist into December.
Viburnum dilatatum
linden viburnum
Adoxaceae
Habit: Shrub
Leaves: Opposite, *three-lobed, maple-like leaves. Mostly glabrous on top, can be slightly pubescent on bottom especially on young leaves. Petiole with disk-like glands. Petiole grooved.
Twigs and Stems: Stout, ribbed, *buds plump, 2 scaled, reddish glabrous, widest above middle.
Flowers: Lacecap inflorescence. Flowers bloom in mid-May,
Fruits: Smell like vomit but birds like them
Viburnum opulus
European cranberrybush viburnum
Adoxaceae
Habit: Shrub or low tree
Leaves: *Opposite, *palmately compound leaves with 5-7 leaflets of various sizes. Leaves with blue-gray-tomentum.
Flowers: Inflorescence is a panicle of small clusters of fragrant lavender flowers found on the current year’s growth. Blooms August - October.
Twigs and Stems: Square to nearly square in cross section; leaf scar is U-shaped. Stems bright green on upper side; below they are darker green with a maroon tint. Twigs densely hairy.
*Helpful ID feature when leaves are off: All parts of plant are very fragrant, including the stems
Vitex agnus-castus
chastetree
Verbenaceae
Habit: Shrub or small tree
Leaves: *Opposite or subopposite, simple, elliptic, broadest at the middle, 3” - 8” long. Leaf apex typically abruptly acuminate. Margin is entire and it is slightly thickened because it is inrolled. Light green on bottom, dark green on top.
Twigs and Stems: *Stout, squarish stem, flattened at the tip. Terminal bud subtended by smaller, opposite lateral buds. *Lateral buds often superposed. Keeled bud scales - with ridge down center. Bud scales loose, brownish with white margin.
Flowers: Showy white flowers in drooping clusters. Petals are very narrow, fringe-like.
Chionanthus virginicus
fringe tree
Oleaceae
Habit: Shrub
Leaves: Alternate, simple, obovate with sharply serrate margins.
Twigs and Stems: Brown, rounded or 3-sided. Twigs will wind around with no distinct pattern. Older wood is smooth and dark brown with no lenticels.
Flowers: Elongate, narrow racemes of white incredibly fragrant flowers blooming in summer.
Fruits: Elongate cluster of three-valved, globose, greyish-brown capsules persists through winter.
Clethra alnifolia
summersweet
Clethraceae
Habit: Shrub
Leaves: Alternate, simple, entire, oval to obovate.
Twigs and Stems: Twigs mostly slender and *with purplish to purplish brown cast; numerous twigs arising from near the same point. *Stems stout, tannish with dark blotch at leaf scar; *strong odor when cut or crushed; sap runs when stem is cut. Pith orange colored. Bark with some exfoliation of surface layers.
Fruits: *Great masses of feathery panicles from June through August (on female plants). Old fruits persist through the winter
Cotinus coggygria
smokebush
Anacardiaceae
Habit: Tree
Leaves: Alternate, simple, ovate to elliptic, entire, lustrous dark green above, pale beneath; Petiole 0.33” - 1”. Pubescent to tomentose.
Fruit: *Globose berry (fleshy fruit from a single ovary), 1” - 2” long, yellow-orange; persistent calyx with four lobes.
Twigs and Stems: Grayish-brown with warty lenticels; no terminal bud; *lateral buds reddish black and distinct from stem. Leaf scars raised. Old fruit scar is flat topped and circular.
Diospyros virginiana
persimmon
Ebenaceae
Habit: Shrub
Leaves: Alternate, simple, 2” - 6” long, ovate to rounded *unequal bases. *Margins crenate to dentate on upper half of leaf. Leaves glabrous above, with silvery pubescence beneath (white underneath leaf). Veins raised on the bottom. *Foliage ends on the vein at the leaf base leaving a distinct gap.
Twigs and stems: No terminal bud present. Leaf scar has one trace.
Flowers: White, fragrant. *Blooms early spring.
Stems: *Buds stalked.
Fothergilla gardenii
dwarf fothergilla
Hamamelidaceae
Habit: Tree
Leaves: Alternate, simple, 2” - 6” long, *unequal bases. *Margins irregularly crenate-dentate, especially on upper half of leaf. Leaves glabrous above, with stellate (star shaped) hairs on midrib and veins beneath; petiole downy.
Twigs and Stems: Pubescent, green but maturing to brown. *Buds stalked, downy; foliar buds naked; flower buds globose.
Flowers: *Blooms October-November. Yellow, fragrant, with 4 strap-like yellow petals; 4 stamens; calyx dull brown outside, yellow inside.
Fruit: 2-valved capsule containing 2 shiny black seeds. Fruits mature the summer following flower blooming
Hamamelis virginiana
common witchhazel
Hamamelidaceae
Habit: Vine
Leaves: Opposite, simple, broadly ovate to ovate-oval, acute or acuminate tipped, *serrate margin.
Twigs and Stems: Climbs by aerial rootlets; brown exfoliating bark curls conspicuously. Young twigs light green, abruptly turning reddish-brown with age.
Flowers: Marginal flowers sterile with four showy white sepals
Hydrangea anomala ssp. petiolaris
climbing hydrangea
Hydrangeaceae
Habit: Low growing, clumpy, rounded shrub. Broader than high at maturity.
Leaves: Opposite, simple, ovate to elliptic, 2-8” long, 2-6” wide, rounded or cordate at base, *serrate margin, glabrous.
Twigs and Stems: Prominent buds and thick stem. Shiny, young branches glabrous, and smooth. Older stems exfoliating. Large, white or hollow pith.
Flowers: Lacecap type corymb inflorescence, 4-6” wide. Fertile flowers (center) are dull white June through September.
Fruit: Infrutescences persist into winter and are somewhat ornamental.
Hydrangea arborescens ‘Dardom’
White Dome® smooth hydrangea
Hydrangeaceae
Habit: Low growing, clumpy, rounded shrub. Broader than high at maturity.
Leaves: Opposite, simple, ovate to elliptic, rounded or cordate at base, *serrate margin, glabrous.
Twigs and Stems: Prominent buds and thick stem. Shiny, young branches glabrous, and smooth. Older stems exfoliating. Large, white or hollow pith.
Flowers: Produces huge hortensia-type flowers (as much as 12” across) which open green, then mature to white before turning green at the end of their life cycle. The flowers are held upright on very sturdy stems, so they don’t flop like ‘Annabelle’ will.
Hydrangea arborescens ‘Abetwo’ PP# 20571
Incrediball® hydrangea
Hydrangeaceae
Habit: Shrub
Leaves: *Opposite, *distichous, coarsely serrate large (4”-8” long, to 4” wide) leaves with smooth surface (H. paniculata is pubescent). Leaf veins are thick and lighter green than the rest of the blade.
Flowers: Hortensia type (a.k.a. snowball) or lacecap type inflorescence depending on the cultivar. Hortensia – all flowers are alike, petals are large and all flowers are sterile. *In acidic soils (pH<6.5) flowers are blue, in alkaline soils (pH>6.5) flowers are pink. Old flowers exposed to sun will be pale pinkish until they turn brown in fall. Without sun older flowers will be green. *Hortensia type inflorescences are persistent and dry well. They have excellent value as ‘trees’ in landscape models.
Twigs and Stems: Prominent buds and thick stem. Twigs bright green. Older stems pithy or hollow
Hydrangea macrophylla
bigleaf hydrangea
Hydrangeaceae
Habit: Shrub
Leaves: *Opposite, *large with 3 - 7 lobes, reminiscent of oak leaves. Undersides have raised, pubescent veins.
Flowers: Pyramid-shaped inflorescence similar to a lace-cap type. Bracts of lateral sterile flowers white when young, pinkish-brown to brown with age. Fruits not showy, but persist through winter.
Twigs and Stems: Twigs are thick, orangey-tan colored with felt-like pubescence; stems are brownish with prominent lenticels. Terminal buds huge, naked, and much larger than laterals; rusty colored with felt-like texture. Older bark exfoliates.
Hydrangea quercifolia
oakleaf hydrangea
Hydrangeaceae
Habit: Shrub with erect, clustered branches. Will form colonies in moist soils. Often low and arching.
Leaves: Alternate, bright to dark green in summer changing to orange or reddish-purple, and scarlet in fall. Semi-evergreen leaves often persist deep into fall and occasionally a few will linger through winter.
Flower: White, 1/3” to ½” diameter flowers born on 2-6” long racemes.
Fruit: 5-valved capsule. ¼” long, and *persistent through winter into the following year.
Twigs and Stems: Fine, green to reddish-purple, leaf scars are crescent shaped.
Itea virginica
Virginia sweetspire
Iteaceae
Habit: Broad, shrub, 3-4’ high and 4-5’ wide at maturity.
Leaves: *Alternate, sharply toothed; *white to light yellow chimeral sections and streaks in some leaves.
Twigs and Stems: Branched often, reddish brown, slender and brittle.
Flowers: June-August; deep pink corymbs
Spiraea ×bumalda ‘Anthony Waterer’
Anthony Waterer spirea
Rosaceae
Habit: Shrub
Leaves: Alternate; *bi- to tri-pinnately compound, may be as large as 4’ long; *rachis with prickles.
Twigs and Stems: Stout, *with prickles especially at the base of the leaf scar; leaf scar almost encircles the stem.
Flowers: Large clusters of small white flowers in summer.
Fruits: Purple-black drupes in early fall.
Aralia spinosa
Devil’s walking stick
Araliaceae
Habit: Tree
Leaves: *Opposite, subopposite, to fully alternate on same branch; blue green in early spring and summer. Crenate (scallop) or serrate margins. Name implies similarity to redbud (Cercis). Leaves with caramel aroma when they senesce in fall.
Twigs and Stems: Slender, swollen at nodes, no true terminal bud. *Buds with chunky “crab claw” appearance. Small spur shoots common..
Cercidiphyllum japonicum
Katsura tree
Cercidiphyllaceae
Habit: Tree
Leaves: Alternate, simple, with parallel veins that end in a spine - more veiny; juvenile foliage persists in winter. *Leaves glabrous.
Twigs and Stems: Twigs gray. *Glabrous. *Buds tan to brown, imbricate, narrow, up to 1” long, sharply pointed. Bark light gray, smooth, sinuous.
Fruits: 4-sided involucre surrounds nut; 1/2”-3/4”
Fagus grandifolia
American beech
Fagaceae
Habit: Tree
Leaves: Alternate, simple, *”wavy margins”, veins parallel and straight. Color varies with cultivar, this cultivar consistently purplish. *Leaves usually hairy on margins, petioles and veins on lower surface.
Twigs and Stems: Brown; with villous hairs. Buds imbricate 1” long, pointed. Dark grey smooth sinuous bark like elephant hide.
Fruits: A nut, covered with prickly, 4 side involucre: 1-1 1/2” wide.
Fagus sylvatica
European beech
Fagaceae