New York Metropolitan Flora

Common Names

Downy Arrow-wood

Field Identification

Shrub with opposite toothed leaves; with clusters of small white flowers followed by dark blue-black berries.

Other uses

Rehder, 1940 Flint, 1983

Used as an ornamental in landscaping situations, hardy to USDA zone 2-3.

---

Nomenclature

Viburnum rafinesquianum Schultes in Roemer & Schultes, Syst. Veg. 6: 630. 1820.
?Viburnum asuminatum W. Young, Cat. Arb. Arbust. Am. 26. 1783.
Viburnum villosum Raf., Med. Repos. New York hex. 2, 5: 361. 1808, not Swartz 1788.
Viburnum pubescens sensu Gray, Syn, Fl. N. Am. 1,2: 11. 1824, p.p.; not Pursh 1814.
Viburnum affine Bush ex Rehd. in Sargent, Trees & Shrubs 1: 135. 1903.
Viburnum pubescens var. affine Rehd., Mitt. Deutsch. Dendr. Ges. 1913(22): 263. 1913.
*Viburnum affine var. hypomalacum Blake, Rhodora 20: 14. 1918.
*Viburnum rafinesquianum var. affine House, Torreya 35: 126. 1935.
TYPE: unknown

Description

HABIT Perennial, deciduous, phanerophytic, shrub, 1-2 m tall.

STEMS Main stems ascending or erect, round. Bark smooth, not exfoliating, brown. Branches ascending. Twigs brown, not odoriferous, terete, 1.5-3 mm in diam., smooth, glabrous or occasionally very sparsely hairy, eglandular. Pith white, round, continuous, nodal diaphram absent. Sap translucent. For a detailed discussion of stem architecture see Donoghue, 1981. For a detailed analysis of the root anatomy see Gasson, 1979.

BUDS Terminal and axillary present, monomorphic, scattered along stem; 3 mm long, blunt; axillary buds 2 per axil, 3 mm long, blunt. Bud scales orange or brown, chartaceous, glabrous (minutely ciliate along margins), eglandular. Bud scale scars not encircling the stem. Leaf scars thinly crescent-shaped. Vascular bundle scars 3.

LEAVES Opposite, simple, spiral, 2 per node, divergent from stem. Stipules present, lateral, persistent, adnate with the petiole, linear leaf-like, margins ciliate. Leaves petiolate, petiole furrowed, 0.3-1 cm long, with long and unbranched hairs or with two to five-armed fasciculate-stellate hairs erect, moderately dense, distributed throughout. Not glabrescent, eglandular. Leaf blades: abaxial surface light green, adaxial surface green, lanceolate or ovate, bilaterally symmetric, 3-7 cm long, 2-4.5 cm wide, chartaceous, base obtuse or subcordate, margin toothed, dentate, apex acuminate or acute, abaxial surface with long and unbranched hairs or with two to five-armed fasciculate-stellate hairs, erect or spreading, white, moderately dense, distributed throughout. Not glabrescent, eglandular. Adaxial surface with long and unbranched hairs, erect or spreading, white, sparse, distributed throughout, eglandular.

INFLORESCENCES Bisexual, compound, terminal umbelliform cyme. Peduncle 1.5-4 cm long (rarely sessile), peduncle & rays beset with red-orange glands. Rachis absent. Bracts sessile, linear triangular, apex acute, caducous. With long and unbranched hairs, hairs erect or spreading, white, sparse, distributed throughout, with sessile, reddish-orange glands. Bracteoles 0 or 1, at base of pedicel or at apex of pedicel, bracteoles: abaxial surface light yellow or light yellowish green, linear triangular, apex acute, with long and unbranched hairs, with sessile, red-orange glands, caducous.

FLOWERS Serotinous, formed on last season's growth, bisexual, with sepals and petals readily distinguishable from one another, 5-merous, fragrance absent. Calyx actinomorphic, tubular, of fused sepals, persistent, abaxial and adaxial surfaces light yellowish green or light green, tube 1.5 mm long, 0.75 mm wide. Sepal lobes 5, triangular, margin ciliate, apex acute, abaxial surface glabrous, eglandular, distal end of lobes tinged with red. Corolla actinomorphic, of fused petals, deciduous, abaxial and adaxial surfaces white or light yellow. Petal lobes 5, 2 mm long, margin entire, apex obtuse, abaxial surface glabrous, eglandular. Gynoecium syncarpous. Carpels 1. Locules 3, 2 abortive, 1 fertile. Stigmas 1, 3-lobed on a short stylopodium at the top of the ovary. Styles 1, short, conical, glabrous. Ovary inferior. Placentation axile or parietal. Androecium epipetalous, exserted, haplostemous. Stamens 5. Anthers yellow, glabrous, eglandular. Filaments straight, white, glabrous, adnate to base of petals.

FRUITS Drupe, dark blue, ellipsoid, 8-10 mm long, 5-6 mm wide, glabrous, eglandular.

SEEDS Seeds 1, yellow, lenticular, 6-7 mm long, 4-4.5 mm wide, eglandular, pusticulate.

Habitat

Mesic to dry upland woods and hill tops.

Distribution

Native to eastern North America.

United States -- AL, AR, CT, DE, GA, IA, IL, IN, KY, MA, MD, MI, MN, MO, NC, ND, NH, NJ, NY, OH, OK, PA, SC, SD, TN, TX, VA, VT, WI, WV

Canada -- MB, ON, QC

New York Metropolitan Region -- Located in the northern and western regions of the metropolitan area.

Rarity Status

Heritage Global Rank -- G5

Connecticut -- Not listed

New Jersey -- Not listed

New York -- Not listed

Species Biology

Flowering May [week 3] - June [week 2]

Pollination

Waldbauer, 1984

Mycophily -- Temnostoma spp.

Fruiting July [week 2] - September [week 2]

Dispersal

Martin, 1951 Ridley, 1930

Endozoochory -- via avian frugivores: Pinicola enucleator (Pine Grosbeak), Bonasa umbellus (Ruffed Grouse), Phasianus colchicus (Ring-necked Pheasant), Meleagris gallopava (Turkey), Turdus migratorius (Robin), Sturnus vulgaris (Starling), Catharus minimus (Gray-cheeked Thrush), Catharus guttata (Hermit Thrush), Catharus ustulata (Olive-backed Thrush), Myiarchus crinitus (Great Crested Flycatcher), Bombycilla cedrorum (Cedar waxwing), Dryocopus pileatus (Pileated Woodpecker), Cardinalis cardinalis (Cardinal)

Mammals: Peromyscus spp.(White-footed Mice), Tamias striatus (Chipmunk), Euarctos americanus (Black Bear), Vulpes fulva (Red Fox), Sciurus carolinensis (Eastern Gray Squirrel), Sciurus niger (Eastern Fox Squirrel), Sylvilagus floridanus (Cottontail Rabbit), Mephitis mephitis (Skunk)

Germination

Fedec, 1973 Giersbach, 1937 Schopmeyer, 1974

Viburnum seed is slow to germinate and most species have embryo dormancy as well as seedling (epicotyl) dormancy. Germination is epigeous. Stratification at a constant 20 degrees C or a daily alternating temperature of 20 to 30 degrees C for germination followed by a low temperature pre-treatment for seedling production generally gives the best results. Seedling dormancy might be overcome by removal of the cotyledons or by a treatment of gibberellic acid (GA3). Seed can probably be stored in a sealed container at 41 degrees F with little loss of viability after one to two years.

Dried seeds can be stored at low temperature for several years. Young, 1992