Quercus dilatata Raf.
black jack oak
A slow-growing, spreading tree eventually reaching up to 15m tall with deeply-cracked bark on mature specimens. Leaves up to 18cm long are three-lobed, glossy and dark green above with hairy, yellowish-brown undersides. Insignificant spring flowers are followed by small acorns in autumn
Size
Ultimate height
Higher than 12 metresTime to ultimate height
20–50 yearsUltimate spread
Wider than 8 metresGrowing conditions
Moisture
Moist but well–drained, Well–drainedpH
Acid, NeutralColour & scent
| Stem | Flower | Foliage | Fruit | |
| Spring | Green | |||
|---|---|---|---|---|
| Summer | Green | |||
| Autumn | Brown Yellow | |||
| Winter |
Position
- Full sun
Aspect
East–facing or North–facing or South–facing or West–facing
Exposure
Exposed or Sheltered Hardiness
H6Botanical details
- Family
- Fagaceae
- Native to GB / Ireland
- No
- Foliage
- Deciduous
- Habit
- Spreading branched
- Potentially harmful
- Pets (dogs): Harmful if eaten - for further information and contact numbers regarding pets, see the HTA guide to potentially harmful plants
- Genus
Quercus can be deciduous or evergreen trees or shrubs, with entire, lobed or toothed leaves; flowers inconspicuous, followed by characteristic acorns; sometimes good autumn colour
- Name status
Correct
- Plant range
- C & CE USA
How to grow
Cultivation
Grow in a well-drained, preferably acidic soil in full sun; tolerates poor soils and drought conditions
Propagation
Propagate by seed or by grafting
Suggested planting locations and garden types
- Low Maintenance
Pruning
Pests
May be susceptible to oak processionary moth, aphids, caterpillars, leaf-mining moths and oak gall wasps
Diseases
May be susceptible to powdery mildews amd honey fungus
Get involved
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