17. Quercus lyrata Walter (overcup oak)
Pl. 417 d, e;
Map 1855
Plants trees to
20 m tall. Bark light ashy gray, divided into loose plates. Twigs 2.0–3.5 mm
wide, brown or gray, glabrous or with scattered spreading hairs. Buds grayish
brown, 2–4 mm long, finely and minutely pubescent. Petioles 3–27 mm long. Leaf
blades 11–24 cm long, 8.0–12.5 cm wide, relatively thin and flexible, usually
acutely angled or tapered at the base, sometimes rounded-obtuse, divided 60–80%
of the width, the lobes 3–5(6) per side, the sinuses often much shallower in
the apical half of leaf; well-developed lobes 11–42 mm wide, ovate or oblong,
sometimes broadened outward, acute to broadly rounded apically, sometimes with
1 or 2 teeth or secondary lobes on each margin; secondary veins 3–7 per side,
some reaching the margin at the tips of the lobes, usually others reaching
toward sinuses and turning aside before reaching the margin; the upper surface
dull or somewhat shiny, glabrous or with scattered, single or paired hairs, the
undersurface green or white, usually with scattered, 1–4-rayed, spreading
hairs, sometimes with appressed-stellate hairs and with appressed unbranched
hairs, usually felty to the touch. Acorn stalks 5–33 mm long, the cup
(17–)21–31 mm long, (9–)18–21 mm wide, broadly urn-shaped to nearly globose,
covering most or all of the nut, the outer surface with the scales 3–5 mm long,
those near the cup margin much narrower. Nuts 9–20 mm long, 14–28 mm wide,
broadly top-shaped. April–May.
Scattered in the
southeastern quarter of the state, west locally to Taney County (southeastern
U.S. west to Missouri, Oklahoma, and Texas). Bottomland forests, swamps,
sloughs, banks of streams, and rarely sinkholes.
When the
undersurface of the leaf is densely covered with stellate hairs, it appears
white. If the stellate hairs are sparse or absent, the leaf is green on both
sides. The green form has been called f. viridis Walter. Hybrids have
been recorded with three other oak species in Missouri.