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5.7 Biological Resources

reduce potential indirect impacts such as developing a Lighting Plan
and Landscaping Plan and to create public awareness concerning
multiple urban interface issues. With implementation of the identified
SCs and MMs, impacts to wildlife movement would be less than
significant.

Threshold 7-5 Would the project convert oak woodlands (as defined by the
state, oak woodlands are oak stands with greater than 10%
canopy cover with oaks at least 5 inch in diameter measured at
4.5 feet above mean natural grade) or otherwise contain oak
or other unique native trees (junipers, Joshuas, southern
California black walnut, etc.)?
Threshold 7-6 Would the project conflict with any local policies or ordinances
protecting biological resources, including Wildflower Reserve
Areas (L.A. County Code, Title 12, Ch. 12.36), the Los Angeles
County Oak Tree Ordinance (L.A. County Code, Title 22, Ch.
22.56, Part 16), the Significant Ecological Areas (SEAs) (L.A.
County Code, Title 22, Section 22.56.215), and Sensitive
Environmental Resource Areas (SERAs) (L.A. County Code,
Title 22, Ch. 22.44, Part 6)?

The analysis of oak tree impacts, as well as related mitigation measures and PDFs, are
generally consistent with the OWCMP, because they consider the ecological function of the
woodland habitat and examine functions at several spatial levels.

On-Site Impacts

Oak Trees

The County of Los Angeles Oak Tree Ordinance (CLAOTO) protects oak trees in
unincorporated areas of Los Angeles County that are 25 inches or more in circumference
(8 inches in diameter) as measured 4.5 feet above mean natural grade; in the case of oaks
with more than 1 trunk, the ordinance protects those trees with a combined circumference
of any 2 trunks of at least 38 inches (12 inches in diameter), as measured 4.5 feet above mean
natural grade (LACDRP 1988). A “Heritage Oak”, as defined by CLAOTO, is any oak tree that:
(1) measures 36 inches or more in diameter, as measured 4.5 feet above the natural grade
or (2) any oak less than 36 inches in diameter having a significant historical or cultural
importance to the community. CLAOTO requires that all potential impacts to oak trees be
preceded by an application to the County that includes a detailed Oak Tree Report, and that
requires mitigation for impacts to oak trees (which may include the replacement of oak trees
at a ratio of at least two to one [2:1]; this ratio may be greater if required as a condition in
the County-issued Oak Tree Permit) (LACDRP 1988).

The Project site contains an estimated 181,070 oak trees of all sizes; of these, an estimated
33,861 oaks under the jurisdiction of CLAOTO are present on the site; an estimated
91 regulated oaks would be directly impacted by the Project (see Exhibit 5.7-14, Oak Tree
Impacts) (Tree Life Concern 2008, 2003; BonTerra Consulting 2009a). Of the oaks to be

R:\Projects\PAS\CEN\000306\Draft EIR\5.7 Bio_051117.docx 5.7-171 Centennial Project
Draft EIR