Quercus alba

white oak

chene blanc

Did you know?:

In the past, Quercus alba was considered the source of fine and durable lumber for furniture and shipbuilding in America. Over time it has been replaced by faster-growing and better-yielding species lacking tyloses (enabling the wood to be more suited for pressure treating). It is still used for furnishings, barrels, and fuel. Native Americans used the tree for food and medicinally for a great many symptoms. Many animals feed on the plant, and, for more than 180 species of birds and mammals, its acorns are an important food.

Photo Credit:

What does this species look like?

White oak is a deciduous tree growing 60 to115 feet tall. Male and female flowers are separate on the same tree. Many tiny, male flowers are grouped into yellowish to green caterpillar-like clusters (catkins) that hang down, The tiny, reddish female flowers occur on a tiny spike and are surrounded by a cupule (what will become the acorn cap). Flowering begins when trees mature as early as 20 years old, but generally between 50 and 200 years of age. The flowers are wind-pollinated.

White oak favors coarse, deep, moist, well-drained, slightly acid soils, but often occurs on loam or clay soils. It is found in dry to moderately moist woodland communities in rich uplands, moist bottomlands, sandy plains, on dry, gravelly slopes, and along streams. It is sensitive to flooding, fire injury, coal smoke, and fly ash deposits on the soil surface and is resistant to salt-spray and brief submergence in salt water. Its tolerance to shade diminishes with age; its site needs at least 35% full sunlight for seedling success.

Why observe this species?

White oak is a USA-NPN regional plant species. Regional species are ecologically or economically important but are distributed more locally than calibration species. The NPN integrates these observations to understand better plant responses within the different geographic regions of the nation. In addition, this species is an allergen. Observations on its phenology will provide valuable information to benefit people with allergies and the public health community.

Where is this species found?

U.S. States:

AL, AR, CT, DC, DE, FL, GA, IA, IL, IN, KS, KY, LA, MA, MD, ME, MI, MN, MO, MS, NC, NE, NH, NJ, NY, OH, OK, PA, RI, SC, TN, TX, VA, VT, WI, WV

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Special Considerations for Observing

If drought seems to be the cause of leaf color or fall for a plant, please make a comment about it for that observation.

Note that individuals may not produce catkins every year.

Which phenophases should I observe?

Leaves	Do you see...? *Breaking leaf buds* One or more breaking leaf buds are visible on the plant. A leaf bud is considered "breaking" once a green leaf tip is visible at the end of the bud, but before the first leaf from the bud has unfolded to expose the leaf stalk (petiole) or leaf base. How many buds are breaking? Less than 3 3 to 10 11 to 100 101 to 1,000 1,001 to 10,000 More than 10,000 More... *Leaves* One or more live, unfolded leaves are visible on the plant. A leaf is considered "unfolded" once its entire length has emerged from the breaking bud so that the leaf stalk (petiole) or leaf base is visible at its point of attachment to the stem. Do not include fully dried or dead leaves. What percentage of the canopy is full with leaves? Ignore dead branches in your estimate. Less than 5% 5-24% 25-49% 50-74% 75-94% 95% or more More... *Increasing leaf size* A majority of leaves on the plant have not yet reached their full size and are still growing larger. Do not include new leaves that continue to emerge at the ends of elongating stems throughout the growing season. What percentage of full size are most leaves? Less than 25% 25-49% 50-74% 75-94% 95% or more More... *Colored leaves* One or more leaves (including any that have recently fallen from the plant) have turned to their late-season colors. Do not include fully dried or dead leaves that remain on the plant. What percentage of the canopy is full with colored leaves? Less than 5% 5-24% 25-49% 50-74% 75-94% 95% or more More... *Falling leaves* One or more leaves are falling or have recently fallen from the plant. More...
Flowers	Do you see...? *Flowers or flower buds* One or more fresh open or unopened flowers or flower buds are visible on the plant. Include flower buds that are still developing, but do not include wilted or dried flowers. For Quercus alba, the male inflorescence is a catkin which is initially compact and stiff, but eventually unfolds to become longer and hang loosely from the branch. Female flowers are very small and petal-less, emerging from the growing stem at the point where a new leaf is attached. How many flowers and flower buds are present? For species in which individual flowers are clustered in flower heads, spikes or catkins (inflorescences), simply estimate the number of flower heads, spikes or catkins and not the number of individual flowers. Less than 3 3 to 10 11 to 100 101 to 1,000 1,001 to 10,000 More than 10,000 More... *Open flowers* One or more open, fresh flowers are visible on the plant. Flowers are considered "open" when the reproductive parts (male stamens or female pistils) are visible between or within unfolded or open flower parts (petals, floral tubes or sepals). Do not include wilted or dried flowers. For Quercus alba, the male flowers will open once the initially compact catkin has unfolded and is hanging loosely. Female flowers are open when the pistils are visible, but will be very difficult to see where they are out of reach. What percentage of all fresh flowers (buds plus unopened plus open) on the plant are open? For species in which individual flowers are clustered in flower heads, spikes or catkins (inflorescences), estimate the percentage of all individual flowers that are open. Less than 5% 5-24% 25-49% 50-74% 75-94% 95% or more More... *Pollen release* One or more flowers on the plant release visible pollen grains when gently shaken or blown into your palm or onto a dark surface. How much pollen is released? Little: Only a few grains are released. Some: Many grains are released. Lots: A layer of pollen covers your palm, or a cloud of pollen can be seen in the air when the wind blows More...
Fruits	Do you see...? *Fruits* One or more fruits are visible on the plant. For Quercus alba, the fruit is a nut (acorn), partially covered with a "cap", that changes from green to yellow-green to light brown or dark red brown. How many fruits are present? Less than 3 3 to 10 11 to 100 101 to 1,000 1,001 to 10,000 More than 10,000 More... *Ripe fruits* One or more ripe fruits are visible on the plant. For Quercus alba, a fruit is considered ripe when it has turned light brown or dark red brown. What percentage of all fruits (unripe plus ripe) on the plant are ripe? Less than 5% 5-24% 25-49% 50-74% 75-94% 95% or more More... *Recent fruit or seed drop* One or more mature fruits or seeds have dropped or been removed from the plant since your last visit. Do not include obviously immature fruits that have dropped before ripening, such as in a heavy rain or wind, or empty fruits that had long ago dropped all of their seeds but remained on the plant. How many mature fruits have dropped seeds or have completely dropped or been removed from the plant since your last visit? Less than 3 3 to 10 11 to 100 101 to 1,000 1,001 to 10,000 More than 10,000 More...

Leaves

Do you see...?

Breaking leaf buds
One or more breaking leaf buds are visible on the plant. A leaf bud is considered "breaking" once a green leaf tip is visible at the end of the bud, but before the first leaf from the bud has unfolded to expose the leaf stalk (petiole) or leaf base.

How many buds are breaking?

Less than 3

3 to 10

11 to 100

101 to 1,000

1,001 to 10,000

More than 10,000

More...

Leaves
One or more live, unfolded leaves are visible on the plant. A leaf is considered "unfolded" once its entire length has emerged from the breaking bud so that the leaf stalk (petiole) or leaf base is visible at its point of attachment to the stem. Do not include fully dried or dead leaves.

What percentage of the canopy is full with leaves? Ignore dead branches in your estimate.

Less than 5%

5-24%

25-49%

50-74%

75-94%

95% or more

More...

Increasing leaf size
A majority of leaves on the plant have not yet reached their full size and are still growing larger. Do not include new leaves that continue to emerge at the ends of elongating stems throughout the growing season.

What percentage of full size are most leaves?

Less than 25%

25-49%

50-74%

75-94%

95% or more

More...

Colored leaves
One or more leaves (including any that have recently fallen from the plant) have turned to their late-season colors. Do not include fully dried or dead leaves that remain on the plant.

What percentage of the canopy is full with colored leaves?

Less than 5%

5-24%

25-49%

50-74%

75-94%

95% or more

More...

Falling leaves
One or more leaves are falling or have recently fallen from the plant. More...

Flowers

Do you see...?

Flowers or flower buds
One or more fresh open or unopened flowers or flower buds are visible on the plant. Include flower buds that are still developing, but do not include wilted or dried flowers. For Quercus alba, the male inflorescence is a catkin which is initially compact and stiff, but eventually unfolds to become longer and hang loosely from the branch. Female flowers are very small and petal-less, emerging from the growing stem at the point where a new leaf is attached.

How many flowers and flower buds are present? For species in which individual flowers are clustered in flower heads, spikes or catkins (inflorescences), simply estimate the number of flower heads, spikes or catkins and not the number of individual flowers.

Less than 3

3 to 10

11 to 100

101 to 1,000

1,001 to 10,000

More than 10,000

More...

Open flowers
One or more open, fresh flowers are visible on the plant. Flowers are considered "open" when the reproductive parts (male stamens or female pistils) are visible between or within unfolded or open flower parts (petals, floral tubes or sepals). Do not include wilted or dried flowers. For Quercus alba, the male flowers will open once the initially compact catkin has unfolded and is hanging loosely. Female flowers are open when the pistils are visible, but will be very difficult to see where they are out of reach.

What percentage of all fresh flowers (buds plus unopened plus open) on the plant are open? For species in which individual flowers are clustered in flower heads, spikes or catkins (inflorescences), estimate the percentage of all individual flowers that are open.

Less than 5%

5-24%

25-49%

50-74%

75-94%

95% or more

More...

Pollen release
One or more flowers on the plant release visible pollen grains when gently shaken or blown into your palm or onto a dark surface.

How much pollen is released?

Little: Only a few grains are released.

Some: Many grains are released.

Lots: A layer of pollen covers your palm, or a cloud of pollen can be seen in the air when the wind blows

More...

Fruits

Do you see...?

Fruits
One or more fruits are visible on the plant. For Quercus alba, the fruit is a nut (acorn), partially covered with a "cap", that changes from green to yellow-green to light brown or dark red brown.

How many fruits are present?

Less than 3

3 to 10

11 to 100

101 to 1,000

1,001 to 10,000

More than 10,000

More...

Ripe fruits
One or more ripe fruits are visible on the plant. For Quercus alba, a fruit is considered ripe when it has turned light brown or dark red brown.

What percentage of all fruits (unripe plus ripe) on the plant are ripe?

Less than 5%

5-24%

25-49%

50-74%

75-94%

95% or more

More...

Recent fruit or seed drop
One or more mature fruits or seeds have dropped or been removed from the plant since your last visit. Do not include obviously immature fruits that have dropped before ripening, such as in a heavy rain or wind, or empty fruits that had long ago dropped all of their seeds but remained on the plant.

How many mature fruits have dropped seeds or have completely dropped or been removed from the plant since your last visit?

Less than 3

3 to 10

11 to 100

101 to 1,000

1,001 to 10,000

More than 10,000

More...

For more information

USDA PLANTS profile for white oak (USDA Symbol: QUAL)
ITIS information for white oak (ITIS TSN: 19290)

Acknowledgments

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