Basic Information
Common Name: Engelmann Oak
Scientific Name: Quercus engelmannii
Species Code: QUEENG
Management Category: VF (species with limited distribution in the MSPA or needing specific vegetation characteristics requiring management)
Occurrence Map
Table of Occurrences

Goals and Objectives

Goal: Maintain, enhance and restore oak woodlands on Conserved Lands in the MSPA that support or have the potential to support VF species (i.e., Engelmann Oak, California newt) and coast live oak woodlands that incidentally benefit a diverse array of other MSP species (e.g., Harbison's dun skipper, California newt, pallid bat, mountain lion) so that the vegetation communities have high ecological integrity, and these species are resilient to invasive pests and disease pathogens, environmental stochasticity, threats and catastrophic disturbances, such as very large wildfires and intense and prolonged drought, and will be likely to persist over the long term (>100 years).

Regional NFO 2021 VF
MON-IMP-MONPL QUEENG-1

Management units: 2, 3, 4, 5, 6, 8, 9, 10, 11

In 2021, conduct Engelmann oak woodland monitoring as part of implementation of the Oak Woodland Vegetation Monitoring Plan on Conserved Lands in the MSPA.

Action Statement Action status Projects
IMP-1 Submit project metadata, monitoring datasets and reports to the MSP web portal waiting for precedent action
Criteria Deadline year
Oak Woodland Vegetation Monitoring Plan implemented 2021 2021
Threat Name Threat Code
Altered fire regimeALTFIR
Altered hydrologyALTHYD
Climate changeCLICHN
Herbivory/predation
Invasive animalsINVANI
Invasive plantsINVPLA
Loss of ecological integrityECOINT
Parasitism/disease
Urban developmentURBDEV
Code Obj. code Statement
OAKWOO-1 MON-DEV-MAP Starting in 2017, map tree mortality in oak woodlands across the MSPA using high resolution aerial imagery, LIDAR and other remote sensing data and incorporate existing datasets, where available, to determine the current status of oak woodlands in the MSPA that are affected by drought, wildfire and invasive pests and fungal pathogens.
OAKWOO-2 MON-PRP-MONPL Beginning in 2019, prepare an oak woodland vegetation monitoring plan for Conserved Lands in the MSPA to assess tree mortality and recruitment, including that of coast live oak and Engelmann oak, track community composition, structure and ecological integrity, and to document threats and assess environmental conditions. Prepare the oak woodland monitoring to integrate where feasible or bulid upon the results of other monitoring projects such as riparian forest and scrub vegetation monitoring, shothole borer/Fusarium complex monitoring, and golden-spotted oak borer and fungal pathogen monitoring. The monitoring plan should include a conceptual model, specific monitoring questions, the sampling frame within the MSPA, monitoring methods, a statistically valid sampling design, permanent sampling locations, timeline, and standardized protocols. Use the Oak Woodland Tree Mortality map and the distribution of coast live oak and Engelmann oaks to develop a sampling frame and stratified sampling design with permanent sampling plots spanning north to south and east to west environmental gradients across the MSPA. Evaluate ecological integrity at monitoring sites by integrating other types of monitoring into the long-term sampling plots, such as abiotic element monitoring (e.g., automated weather stations and soil sensors, GIS-data layers), ecological integrity monitoring (e.g., plant and animal communities, ecological processes), MSP VF species monitoring, and threats monitoring (e.g., fire, climate change, disease, invasive animals and invasive plants).
OAKWOO-3 MON-IMP-MONPL In 2021, conduct oak woodland monitoring to implement the Oak Woodland Vegetation Monitoring Plan on Conserved Lands in the MSPA.

Current Distribution Rangewide

Eastern Los Angeles County to northwestern Baja California, Mexico [1]. Smallest distribution of any California oak species.

Known Populations in San Diego County

Forty-six occurrences on Conserved Lands in MUs 3 (Crest-Worley Preserve, Hollenbeck Canyon Wildlife Area, Lawrence and Barbara Daley Preserve, Otay Mountain Ecological Reserve, Otay Mountain Wilderness Area, Otay Ranch Preserve, Sycamore Canyon Preserve, Sycuan Peak Ecological Reserve, Wright's Field), 4 (BLM, Boulder Oaks Preserve, Cleveland National Forest, El Capitan Open Space Preserve, El Capitan Reservoir Open Space, Louis A. Stelzer County Park, Mt. Woodson, Mt. Gower Preserve, SDG&E Sunrise Power Link Parcels, Simon Preserve), 5 (Boden Canyon Ecological Reserve, Cleveland National Forest, Hellhole Canyon Preserve, Ramona Grasslands Preserve, Sutherland Reservoir Open Space), 6 (Daley Ranch Open Space Preserve, Hodges Reservoir Open Space, Lake Wolford, Lake Wolford Watershed), 8 (BLM, Cleveland National Forest, Margarita Peak, Mount Olympus Preserve), 9 (Cleveland National Forest, Santa Ysabel East Open Space), 10 (Cleveland National Forest, Eagle Peak Preserve, Mesa Grande Easement, Santa Ysabel West Open Space Preserve), and 11 (Barrett Reservoir Open Space, Cleveland National Forest, Potrero Park, Sunrise Power Link Parcels).

List Status

None [1].

Habitat Affinities

Chaparral, cismontane woodland, riparian woodland, valley and foothill grassland [2]. Found on mesas with elevation range of 700 -1250 meters [3].

Taxonomy and Genetics

Fagaceae family [2]. Known to hybridize with scrub oak species (Q. cornelius-mulleri, Q. berberidifolia, and Q. durata) [3].

Life History Demography

Semi-deciduous tree [4]. Produces acorns within 1 year [5]. May be better adapted for establishment in more exposed habitats than Q. agrifolia because it is less sensitive to moisture loss, will germinate with little or no additional water uptake, is self-rooting, and has delayed shoot development.

Seasonal Phenology

Bloom period March-June [2]. Acorn drop occurs September-November [5].

Pollination Seed Dispersal

Wind-pollinated [3]. No persistent seed bank since acorns do not survive more than 1 year [5].

Threats

Development [2] and lack of natural recruitment due to grazing [4]. Competition for underground resources between oak seedlings and exotic grasses.

Special Considerations:

As a white oak, it is at low risk from Goldspotted Oak Borer (Agrilus auroguttatus) [1]. Poor host plant for grasshoppers [4].

Literature Sources

[1] Drennen, K. L. 2011. “Western Riverside County Multiple Species Habitat Conservation Plan ( MSHCP ) Biological Monitoring Program Engelmann Oak ( Quercus Engelmannii ) Survey Report 2005.” Riverside, CA.

[2] CNPS, Rare Plant Program. 2016. Inventory of Rare and Endangered Plants (online edition, v8-02). California Native Plant Society, Sacramento, CA. http://www.rareplants.cnps.org, accessed 12 September 2016.

[3] Ortego, J., E. C. Riordan, P. F. Gugger, and V. L. Sork. 2012. “Influence of Environmental Heterogeneity on Genetic Diversity and Structure in an Endemic Southern Californian Oak.” Molecular Ecology 21 (13): 3210–23. doi:10.1111/j.1365-294X.2012.05591.x.

[4] Dunning, C. E., R. A. Redak, and T. D. Paine. 2003. “Preference and Performance of a Generalist Insect Herbivore on Quercus Agrifolia and Quercus Engelmannii Seedlings from a Southern California Oak Woodland.” Forest Ecology and Management 174: 593–603. doi:10.1016/S0378-1127(02)00187-1.

[5] Tyler, C. M., B. Kuhn, and F. W. Davis. 2006. “Demography and Recruitment Limitations of Three Oak Species in California.” The Quarterly Review of Biology 81 (2): 127–52. doi:10.1086/506025.

[6] Snow, G E. 1991. “Germination Characteristics of Engelmann Oak and Coast Live Oak from the Santa Rosa Plateau, Riverside County, California.” Vol. USDA Forest.