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Article from New Trees by John Grimshaw & Ross Bayton
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'Quercus buckleyi' from the website Trees and Shrubs Online (treesandshrubsonline.
Tree to 15 m. Branchlets grey, black or reddish brown, smooth or furrowed. Leaves deciduous, 5.5–10 × 5–11 cm, broadly elliptic to obovate or almost circular, glabrous, upper surface glossy green, lower surface coppery green, with tufts of hair in the vein axils, three to four secondary veins on each side of the midrib, margins with five to nine deeply divided lobes, lobes largely triangular, expanding and terminating in spiny bristles (12–35 in total), apex acute to acuminate; petiole 2–4.5 cm long, glabrous. Cupule cup- or goblet-shaped, 1–1.8 × 0.5–1.2 cm, outer surface glabrous, inner surface glabrous but for a few hairs on acorn scar; scales acute, occasionally tuberculate, apices appressed. Acorn broadly ovoid to ellipsoid, one-third to half of its length enclosed in the cupule, 1.2–1.9 cm long, stylopodium may be surrounded by several rings. Fruiting in the following year (USA). Nixon 1997. Distribution USA: Oklahoma, Texas. Habitat Limestone ridges and slopes and along small streams between 150 and 500 m asl. USDA Hardi ness Zone 6. Conservation status Least Concern. Illustration Nixon 1997; NT711.
Quercus buckleyi is frequently confused with Q. texana Buckley and several other Texan red oaks. A key to the group in the wild state is therefore provided below.
1a. | Leaves with petioles 0.5–2 cm long; lamina entire or with 3–5 pronounced lobes or 8–10 teeth or shallow lobes; within USA, restricted to Texas | 2 |
1b. | Leaves with petioles 2–6 cm long; lamina with 5–11 pronounced oblong lobes; within USA, also occurring outside Texas | 3 |
2a. | Tree to 13 m tall; leaves 4.5–14 × 2–12 cm, ovate to elliptic in outline, with 3–5 acute lobes and 9–20 bristles; cupule turbinate or deeply cup-shaped, covering one-third to half of acorn; USA (Texas: Davis, Glass and Chisos Mts.), Mexico (Coahuila) | Q. gravesii |
2b. | Tree to 8 m tall; leaves 4.5–9 × 1–2.5 cm, lanceolate to narrowly elliptic in outline, entire or with 8–10 teeth or shallow lobes, 1–9 bristles; cupule saucer-shaped, covering one-quarter to one-third of acorn; USA (Texas: Chisos Mts.) | Q. graciliformis |
3a. | Tree to 15 m tall; leaf bud scales often distinctly ciliate; mature lamina glabrous below or with minute tufts of tomentum (often detectable only with magnification) in vein axils; USA (Oklahoma, Texas) | Q. buckleyi |
3b. | Tree 25–35 m tall; leaf bud scales usually entire; mature lamina with conspicuous tufts of tomentum (readily discernible to naked eye) in vein axils of lower surface | 4 |
4a. | Cupule with thin wall (< 1.5 mm thick), deeply goblet-shaped, covering one-third to half of acorn, inner surface pubescent; USA (Alabama, Arkansas, Illinois, Kentucky, Louisiana, Mississippi, Missouri, Tennessee, Texas) | Q. texana |
4b. | Cup with thick wall (> 1.5 mm thick), saucer- or cup-shaped, covering one-quarter to one-third of acorn, inner surface glabrous or with ring of hairs around scar; Canada (Ontario), USA (Alabama, Arkansas, Florida, Georgia, Illinois, Indiana, Kansas, Kentucky, Louisiana, Maryland, Michigan, Mississippi, Missouri, Nebraska, North Carolina, Ohio, Oklahoma, Pennsylvania, South Carolina, Tennessee, Texas, Virginia, West Virginia) | Q. shumardii |
Quercus buckleyi is a southern representative of the red oaks, allied to Q. shumardii, but slower growing and remaining a smaller tree, tolerant of drought and alkaline soils (Sternberg 2004). Melendrez (2000) has praised its autumnal colour, and noted the variation between deep to bright red and golden yellow in different localities in the wild. In summer the comparatively small leaves are a dull mid-green, with a red petiole. Quercus buckleyi would seem to be a useful red oak for warm, dry climates. It grows reasonably well in the United Kingdom, a specimen at the Hillier Gardens having reached over 10 m in height (date of planting unknown, but prior to 1976). A younger one (Sir Harold Hillier 563), accessioned as a seedling in 1986, is now c.6 m tall. Eike Jablonski (pers. comm. 2006) collected Q. buckleyi, Q. gravesii and Q. shumardii on the same visit to New Mexico in 2000; all have done well at Ettelbruck and Kruchten, but Q. gravesii has the best autumn colour and Q. shumardii has grown fastest.