Valley Oak

Quercus lobata

Fagaceae · broadleaf deciduous tree · native

Last updated April 25, 2026

Quick Facts

Height

30–90 ft

Spread

30-50 ft

Growth Rate

Fast

Light

Full Sun

Soil

Well Drained

Water

Moderate

Hardiness

Zone Zones 7a–8b

Bloom Time

Mar 1-Mar 31

Fall Color

Brown, yellow

Origin

is limited (endemic) to and widely distributed in

Anthracnose (Shade Trees)High

Primary Spore Release

Cytospora CankerHigh

Spring Canker Activation

Leaf BlisterHigh

Spring Spore Germination and Infection

Nectria CankerHigh

Spore Release (Fall & Spring Rains)

+ 4 more — see full disease and pest lists below

Phenological Calendar

Stage	Typical Window	What to Look For
Bud break BBCH 07	Feb 15-Mar 15	Buds swelling and beginning to open; first green tissue visible
Leaf emergence BBCH 11	Mar 1-Apr 1	First leaves fully unfurled on new growth
Bloom start BBCH 61	Mar 1-Mar 31	First open flowers visible; flowers yellow
Bloom end / petal fall BBCH 69	Apr 1-Apr 15	Last petals falling; flower structures fading
Fruit/seed development BBCH 71	Jun 1-Aug 31	Fruit or seed structures forming; fruit color: brown
Fruit/seed maturity BBCH 85	Sep 1-Nov 30	Fruit fully colored and ripened; seed dispersal may begin
Fall color / leaf senescence BBCH 93	Oct 1-Nov 15	Leaves changing color; fall display beginning
Dormancy BBCH 97	Nov 15-Feb 28	Leafless; no active growth; dormant buds set

Diseases: Regionally Documented (13)

Ramorum Blight (Sudden Oak Death) Mistletoe Armillaria spp. — primarily A Armillaria Root Rot Discula destructiva (dogwood), Kabatiella and Discula spp... Anthracnose Cytospora spp. (Valsa spp., Leucostoma spp.) Cytospora Canker Microstroma album Frosty Mildew Ganoderma applanatum Ganoderma Root and Butt Rot Pseudoinonotus dryadeus Inonotus Root and Butt Rot Taphrina spp. Leaf Blister Phoradendron villosum Mistletoe (a True Mistletoe) Neonectria ditissima Nectria Canker Multiple obligate biotrophic fungi (Erysiphales: Erysipha... Powdery Mildew Inonotus dryophilus White Pocket Rot (Piped Rot)

Pests: Regionally Documented (14)

Looper Stem Gall Asterolecanium spp. Pit scale Platycotis vittata Oak Treehoppers Bucculatrix albertiella Oak Ribbed Casemaker Phylloxera spp. Oak leaf phylloxera Various (Cynipidae, Cecidomyiidae, Eriophyidae, Psyllidae) Leaf galls Neuroterus saltatorius Jumping Oak Gall Andricus quercuscalifornicus California Gallfly Prionoxystus robiniae Carpenterworm Oak gall wasp Bucculatrix ainsliella Oak skeletonizer Edwardsiana rosae Rose leafhopper Various (Cynipidae, Cecidomyiidae, Eriophyidae) Leaf and twig gall

Data Maturity

Structured Multiple sources. Expert review underway.