Young bark=light gray, old bark=​darker gray ridged or flaky;  buds=​short (3–6 mm) (⅛–¼ in)

buds= pointed  or
buds= rounded :

Buds=∩ rounded

trunk bark has ⨇ scales you can easily rub off  or
trunk bark furrowed, has few ⨇ scales you can rub off :

Trunk bark has ⨇ scales you can easily rub off

young twigs have coarse down
post oak  Quercus stellata

young twigs smooth, 🌰︎ acorns paired on long stalks
🇬🇧 English oak  Quercus robur

🌰︎ acorns not on stalks
◼︎ white oak  Quercus alba

Trunk bark furrowed, has few ⨇ scales you can rub off

twigs=thick ⫴ hairy, buds=⫴ hairy
bur oak  Quercus macrocarpa

twigs=thick ⫴ hairy, buds=smooth
♒︎ ◼︎ swamp white oak  Quercus bicolor

Small contorted shrubby tree

all buds=short (<3 mm) (<⅛ in)
scrub oak  Quercus ilicifolia

all buds=long  (>3 mm) (>⅛ in)
◼︎ blackjack oak  Quercus marilandica

Learn more about oak genus Quercus (Quercus spp.)

Part of beech / oak  family Fagaceae in bayberry / beech / birch / oak / walnut  order Fagales.

Native to the temperate and tropical areas in the 🌐︎ Northern Hemisphere, or very close.   🗺 Map by county (🇺🇸 USA-48) (color key).

In many areas:

  • do not move firewood (ever), and
  • do not prune February through June (Texas) or April 15 through July 15 (🇺🇸 USA Midwest and East),
due to possible infestation by oak wilt disease (OWD)  Bretziella fagacearum.

Uses by native peoples
(Ethnobotany database)
  ♧🌰︎☠︎ Leaves and acorns toxic[?] to humans, although many cultures process acorns to remove their tannins, making acorns an important staple food.

Quercus hosts caterpillars of 534 species
of butterflies and moths, in some areas.
  This plant is also known to be a host for (in areas where invasive) 🐝︎ spotted lanternfly (SLF)  Lycorma delicatula.

If your oak is growing a few meters (yards) from a potential parent tree, its acorn probably fell there or was planted by a squirrel  family Sciuridae.

If your oak is growing a kilometer (mile) away from a potential parent tree, its acorn was probably planted by a 🐦︎ jay  family Corvidae, with whom it coevolved.

    — That and lots more interesting information in interview "Our Most Essential Trees: The Nature of Oaks, with Doug Tallamy"  The joe gardener Show.  or its 🔊︎ audio

Oaks account for more tree biomass than any other genus in 🇨🇦 🇺🇸 🇲🇽 North America and México. [1]

🔍︎ 🔍︎ images Discover Life Encyclopedia of Life Michigan Flora (Minnesota) Wild Flower Garden Minnesota Wildflowers Flora of North America NRCS PLANTS db Wikipedia


[1]  "How Oak Trees Evolved to Rule the Forests of the Northern Hemisphere."  Scientific American.  .   Accessed .