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Blackjack Oak

Quercus marilandica
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Quercus marilandica (Blackjack Oak) — botanical photograph
Pl. EBC5 — Quercus marilandica
Quercus marilandicaQuercus marilandicaQuercus marilandicaQuercus marilandicaQuercus marilandicaQuercus marilandicaQuercus marilandicaQuercus marilandicaQuercus marilandicaQuercus marilandicaQuercus marilandicaQuercus marilandicaQuercus marilandicaQuercus marilandica
I

Overview

Blackjack Oak (Quercus marilandica) is a deciduous tree native to the eastern and central United States. It thrives in habitats ranging from Alabama to Virginia, with notable presence in states like Florida, Georgia, Illinois, Indiana, and Kentucky. Known for its edible acorns, which are enjoyed by wildlife and sometimes used in human cuisine, this oak also serves as an ornamental tree due to its distinctive bark and foliage. One of its key features is its ability to grow well in a variety of soil types, from medium to heavy clay, with a preference for light conditions that range from full sun to partial shade. It can reach heights of 10 meters and is hardy in zones 6-9, making it adaptable to different climates within its native range.

Quick answers

What is Blackjack Oak?

Blackjack Oak (Quercus marilandica) is a deciduous tree native to the eastern and central United States. It thrives in habitats ranging from Alabama to Virginia, with notable presence in states like Florida, Georgia, Illinois, Indiana, and Kentucky.

What is Blackjack Oak used for?

Traditionally used for immune support. Each claim is evidence-rated — see Section II for full citations.

Best for
Top 1 evidence-ranked use of Blackjack Oak
Jump to full evidence →
Clinicaluses · safety · chemistry · dosagemedicinal profile
II

Benefits & evidence

1 claim · traditional-use context
Traditional-use context
These notes are presented as ethnobotanical context. No cited clinical references are catalogued for this plant yet.
  • Blackjack Oak, like other oak species, has been traditionally used in Native American medicine to support immune health. A decoction made from the bark may help bolster the body's defenses against common ailments.

    The tannins and flavonoids found in Blackjack Oak bark are thought to have antimicrobial properties that can help protect against pathogens, though the specific mechanisms are not fully characterised.

    ▲ ModerateImmune support →
IV·b

Mixology suggestions

1 draft
Editorial drafts. These pairings are AI-suggested from traditional herbal lore. Always verify with a qualified herbalist before brewing.
Blackjack Oak support blend
general
tea
AI returned a direct ingredient list; normalized into one draft blend for editorial review.
Growingconditions · propagation · uses
V

Cultivation

Blackjack Oak thrives in full to partial sun and prefers well-drained to moist soils with a pH between 4.6 and 5.6. It is hardy in zones 6-9 and can grow up to 10 meters tall. For cultivation, plant the tree in medium to heavy clay soil and ensure it gets plenty of light. Water regularly but avoid overwatering, as it prefers dry conditions. Propagate via seed for best results.
Light
Full sun, Partial sun/shade
Water
Dry, Moist
Soil
Medium, Heavy (clay)
Hardiness
6-9
Habit
Tree, Shrub
Mature size
10.0 m tall
Soil pH
4.6–5.6
For first-time growers

How to grow Blackjack Oak for the first time

8steps

Start with Blackjack Oak as a simple, low-maintenance tree for beginners.

  1. 1

    What you'll need

    Blackjack Oak seeds or young saplings, garden gloves, trowel.

  2. 2

    Best time to plant

    Plant in spring after the last frost or fall before the first freeze.

  3. 3

    Soil and container prep

    Choose a well-draining spot with soil pH between 4.6-5.6; loosen the soil to about 30 cm deep.

  4. 4

    Sowing or transplanting

    Direct sow seeds in fall or stratify them for spring planting; plant young saplings any time of year.

  5. 5

    First two weeks

    Water regularly, keeping the soil moist but not waterlogged. Monitor for pests and diseases.

  6. 6

    Ongoing care

    Provide full sun to partial shade; water when dry; mulch around the base to retain moisture.

  7. 7

    Harvest or pruning

    Prune in late winter before new growth starts to maintain shape and remove dead branches.

  8. 8

    Common mistakes

    Overwatering, planting in heavy clay soil, neglecting mulch application, not providing enough sunlight.

VI

Edible & utility

Edible parts:Seed
Edible uses: Coffee
Other uses:Fire starterTanninLumber
Contextrange · companions · related
VII

Distribution

27 native · 0 introduced
Distribution across1 continent· 27 native
Asia1 region
native (1)Georgia
Broader regions
native:Alabama, Arkansas, Delaware, District of Columbia, Florida, Illinois, Indiana, Iowa, Kansas, Kentucky, Louisiana, Maryland, Mississippi, Missouri, Nebraska, New Jersey, New York, North Carolina, Ohio, Oklahoma, Pennsylvania, South Carolina, Tennessee, Texas, Virginia, West Virginia
IX

Specimen gallery

1 image
Quercus marilandica (Blackjack Oak) — botanical photograph
Blackjack Oak (Quercus marilandica)
X

See also

8 related
XI

Explore further

Growing zone
XII

About this entry

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