North Bay

Mediterranean Forests/Woodlands

 Types: , Mixed Evergreen Forest, Woodlands

 Chaparral: sclerophyllous , poorly developed soils (serpentine), southern exposure/ridges

 Mixed Evergreen Forest: evergreen conifers and hardwoods (many sclerophyllous), deep, organic soils, northern aspect

 Oak Woodlands: different Quercus spp. dominance based on soils and aspect

Sclerophyllous hard & waxy, common in Med. evergreens er

Harding grass here New World Oaks

Distribution of Quercus species in the New World

 Area Number of Species Number of Endemics

 New World 219 219  Mexico 140 81  Central America 25 8  Mexico/Canada/US 194 186  United States 89 46

 California 21 (32 taxa) 7  Sonoma County 10 0  Pepperwood 9 0

Oak Species, Varieties, and Hybrids in California by Lineage Group (Subgenus) Life Form Red Oaks (Erythrobalanus)

* Coast ET Quercus agrifolia var. oxyadenia (var. in S. Cal and Baja) ET Quercus ilex1 Holly Oak (native to Med.) ET * California Black Oak DT var. parvula Oak ES *Quercus parvula var. shrevei Shreve Oak ET *Quercus parvula var. tamalpaisensis Tamalpais oak ES * var. frutescens Dwarf Interior Live Oak ES *Quercus wislizeni var. wislizeni Interior Live Oak ET

Intermediate Oaks (Protobalanus)

Quercus cedrosensis Cedros Island Oak ET * Canyon Live Oak, Golden Oak, Maul Oak ET *Quercus vaccinifolia Huckleberry Oak ES Quercus palmeri Palmers Oak ES Quercus tomentella Island Oak ET

White Oaks (Lepidobalanus)

*Quercus berberidifolia Scrub Oak ES * Blue Oak DT *Quercus durata var. durata Leather Oak ES Quercus durata var. gabrielensis San Gabriel oak ES *Quercus garryana var. breweri Brewer’s Oak DS *Quercus garryana var. garryana Oregon or Garry Oak DT *Quercus garryana var. semota DS * Valley Oak DT *Quercus sadleriana Deer Oak ES Quercus cornelius-mulleri Muller’s Oak ES Quercus dumosa Nuttall’s Scrub oak ES Quercus engelmanii Engelmann or Mesa Oak ET Quercus john-tuckeri Tucker’s Oak ES Quercus pacifica Pacific Oak ES Quercus turbinella Live Oak ES Quercus X acutidens X acutidens (Hybrid of Q. cornelius-mulleri & Q. engelmannii) ETorS Quercus X alvordiana Alford Oak (Hybrid of Q. douglasii & Q. john-tuckeri) ETorS Quercus X macdonaldii MacDonald Oak (Hybrid of Q. berberidifolia & Q. lobata) DT

Lifeform: E = Evergreen, D = Deciduous, T = , S = Shrub * Occurs in northwest California 1 non-native species

Three Major Oak Sub-genera in California

Red Oaks White Oaks Intermediate Oaks California Red Oaks

 5 species: 4 and 1 shrub

 Scaly caps

margins with teeth

 2 year acorn maturation

 Hybrids exhibit reduced fertility

 4 tree species in North Bay: black oak, coast live oak (1 year acorn), Shreve Oak and interior live oak (not common)

Coast Live Oak Interior Live Oak Interior Live Oak stem gall Black Oak Chase oak (Coast L. x Black)

Oracle Oak (Black x Interior)

Shreve Oak California White Oaks

 13 species: 4 trees and 9 shrubs  Bumpy acorn caps  Leaf margin smooth (trees) or toothed (shrubs)  1 year acorn maturation  Hybrids fertile- interesting intermediates and “swarms”  5 species plus hybrids in North Bay- valley, Oregon and blue oaks (trees); leather and California scrub (shrubs) Valley Oak

Valley Oak

Oregon Oak

Blue Oak Epling oak (Oregon x Blue) “Swarm” Epling oak (Oregon x blue) “The acorn shape is Oregon oak-like. The leaf contours are blue oak-like. The specimen is evidence of hybridization in oaks.”

Chaparral Leather Oak Oregon Oak x Leather Oak

California Scrub Oak

© 2008 Keir Morse California Intermediate Oaks

 5 species: 3 trees and 2 shrubs

 Variable acorn caps

 Leaf margin smooth or toothed

 1 year acorn maturation

 Hybrids ??

 1 species in North Bay- canyon live oak Canyon Oak Oak Management Issues

 Douglas-fir encroachment

 Invasive species

 Grazing impacts

 Sudden Oak Death

 Oak phenology and climate change impacts

 Fire, species response and long-term impact on community structure

Some Annadel Douglas-fir Encroachment Resources

Hand Pulling of Seedlings and Saplings

Cool Ground Fire in Woodlands

Conclusions and Recommendations, McBride, 2011

Although the management of Douglas-fir invasion can be deemed successful, it is apparent from the field data that Douglas-fir seedlings continue to become established in the under story of oak dominated woodlands.

Prescribed burning is not recommended as a method for controlling Douglas- fir invasion unless it can be practiced on frequency simulating the frequency of burning by Native Americans in European pre-settlement time (6-20 years; Finny and Martin, 1992).

An experimental program of prescribed burning of several scattered small areas (<1ha) of oak woodland is proposed to test the efficacy and cost effectiveness of small scale prescribed burning as a means of controlling the Douglas-fir invasion. This pattern of burning will more likely simulate the pattern used by the Native Americans.

Sudden Oak Death, C L Oak CA Bay, foliar host

SOD in coast live oak

Oak Phenology and Climate Change

Steve Barnhart SRJC Professor and Pepperwood Academic Director Emeritus [email protected]