8. Viburnum rafinesquianum Schult. (downy arrowwood)

V. rafinesquianum var. affine House

Map 1444, Pl. 338 h

Plants shrubs 1–2 m tall. Bark firm, not peeling, usually relatively smooth to finely roughened or warty on younger branches, rarely somewhat peeling in papery sheets, becoming somewhat fissured on older stems, gray or grayish brown to reddish brown. Winter buds ovoid-conical, slightly flattened, with 2 pairs of overlapping scales, glabrous, not or only slightly sticky. Stipules often present but usually shed early, partially fused to the basal portion of the petiole, linear, hairy and usually also glandular. Petioles 3–15(–22) mm long, unwinged, sparsely to moderately hairy, mostly along the ventral groove, lacking prominent glandular swellings near the tip. Leaf blades (4–)6–10 cm long, 3–7 cm wide, unlobed, relatively thin and papery, ovate to broadly oblong-ovate or occasionally nearly circular, rounded to truncate or shallowly cordate at the base, angled or short-tapered to a bluntly or more commonly sharply pointed tip, the margins coarsely toothed with the teeth 1–3 per cm, 7–12(–14) on each side, the upper surface glabrous or more commonly with scattered, unbranched hairs, the undersurface sparsely to moderately pubescent along the main veins with mostly unbranched hairs and usually also with small patches of densely woolly hairs in the axils of the main veins, often with 3–5 secondary veins on each side crowded near the base of the midvein, pinnately veined above the base, the secondary veins straight, often dichotomously branched but not forming a network, extending to the leaf margin, each branch ending in a tooth. Inflorescences sessile or short- to long-stalked, with (3–)5–7 primary branches, these with dense, minute glands at flowering, the marginal flowers fertile and similar to the other flowers. Ovaries with dense, minute glands. Fruits 6–9 mm long, ellipsoid, oblong-ovoid, or nearly spherical, bluish purple to purplish black, not glaucous. Nutlet 6.0–7.5 mm long, yellowish brown to dark reddish brown. 2n=36. May–June.

Scattered mostly in the eastern half of the state, uncommon or absent from most of western Missouri (eastern U.S. west to North Dakota and Oklahoma; Canada). Bottomland forests, mesic to less commonly dry upland forests, banks of streams and rivers, and bases and ledges of bluffs.

Plants with leaf pubescence absent or limited to the veins have been called var. affine and appear to be the more common phase in Missouri. However, because of the large number of specimens with seemingly intermediate levels of hairiness, it has not been possible to accept the varieties in the present treatment. Steyermark (1963) noted that the fall foliage of this species is attractive, varying from dull purplish red to dull purple with reddish highlights.