2019 Botanical Resources Survey Results Memo (PDF)
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August 27, 2019 Humboldt County Planning & Building Department Page 1 of 4 Reference: 2019 Botanical Resources Survey Results Memo To: Humboldt County Planning & Building From: Yasmine Akky Department Stantec Consulting Services Inc. 3015 H Street 100 California Street, Suite 1000 Eureka, CA 95501 San Francisco CA 94111-4575 Date: August 27, 2019 Reference: Humboldt Wind Energy Project – 2019 Botanical Resources Survey Results Memo INTRODUCTION AND SUMMARY This memorandum summarizes the survey results for botanical resources surveys conducted in 2019 for the Humboldt Wind Energy Project. In 2018, Stantec mapped the vegetation types in the entire project area (2,224 acres) and transportation route. In addition, Stantec conducted a comprehensive botanical survey of approximately 1,736 acres of the project area. The 2019 botanical survey area (1,140 acres; Figure 1) includes the transportation route and portions of the project area that did not receive a comprehensive botanical survey in 2018 due to access constraints during appropriate identification periods of special-status plant species. One new special-status plant species (coast fawn lily) that was not documented during 2018 botanical surveys was identified in the survey area during 2019 surveys. However, based on the current project design, no coast fawn lily will be impacted by the project. In addition, new occurrences of short-leaved evax and Siskiyou checkerbloom were also documented during the 2019 surveys; these populations will also not be impacted by the project. Additional occurrences of a fourth special-status plant species, Pacific gilia, was also documented in 2019. The Draft EIR reported 0.16 acre of temporary impacts to Pacific gilia. With the 2019 survey results and current project footprint, 0.97 acre of Pacific gilia would be temporarily impacted by the project. Pacific gilia is widely distributed in the region, and a temporary impact on 0.97 acre of the occurrences in the project area would not result in a substantial adverse effect on the regional populations of this species. Because the proposed project would temporarily affect a small amount of the available habitat in the project area and would not substantially affect local populations of this species, the potential impacts of project construction and operation on Pacific gilia would continue to be less than significant, as identified in the Draft EIR. Therefore, the survey results presented in this memo are consistent with the conclusions of significance and associated mitigation measures provided within the Draft EIR for the Project. METHODS The methods followed during the 2018 and 2019 botanical resources survey are identical and are described in the Humboldt Wind Energy Project Botanical Resources Report (Stantec 2018). These methods are in accordance with the California Department of Fish and Wildlife (CDFW) Protocols for Surveying and Evaluating Impacts to Special Status Native Plant Populations and Sensitive Natural Communities (California Department of Fish and Wildlife 2018). For the purpose of this evaluation, special-status plant species include plants that are: 1) listed as threatened or endangered under the California Endangered Species Act (CESA) or the federal Endangered Species Act (ESA); 2) proposed endangered or threatened by the U.S. Fish and Wildlife Service; 3) designated as rare by the CDFW; 4) a state or federal candidate species for listing as threatened or endangered; and/or 5) have a California Rare Plant Rank (CRPR) of 1 or 2. Stantec botanists conducted multiple survey passes of the project area and transportation route that covered all safely accessible portions of the 2019 botanical survey area. We completed multiple survey passes (Table 1) to observe early-, mid-, and late-season blooming plants. Incidental observations of special-status or CRPR 3 or 4 plants in the 2018 botanical survey area are included in the 2019 survey results if the occurrences had not previously been documented. The field surveys were floristic in nature; Stantec botanists identified each species observed to the taxonomic level necessary to determine whether the plant was listed as a special-status or CRPR 3 or 4 species or not. Plant taxonomy follows Baldwin et al. (2012), including applicable errata and supplements (Jepson Flora Project 2019). Table 1. Humboldt Wind Energy Project Botanical Survey Dates in 2019 April May June July 8 28 3 8 9 29 4 9 10 30 5 10 11 31 6 11 12 7 12 24 25 26 27 28 RESULTS AND DISCUSSION SPECIAL-STATUS PLANT SPECIES IDENTIFIED IN THE HUMBOLDT WIND ENERGY PROJECT AREA DURING 2019 BOTANICAL SURVEYS Stantec identified four special-status plant species in the project area during the 2019 botanical surveys (Table 2). This includes coast fawn lily (Erythronium revolutum), which was not found in the project area during 2018 botanical surveys. No special-status plant species were identified in the transportation route. Stantec did not document any federally or state listed plant species in the project area or transportation route during the 2019 botanical surveys, nor during the 2018 surveys. The locations of all special-status plant occurrences found in the project area during the 2019 botanical surveys are shown in Figure 1. This figure also includes the results of the 2018 rare plant surveys for context; the survey areas for each year are noted on the figure to differentiate between the results. Table 2. Special-Status Plant Species Identified in the Humboldt Wind Energy Project Area During 2019 Botanical Surveys Species Status1 Number of Occurrences Total Size Estimated (Federal/State/ Identified During 2019 (acres) Number of Plants CRPR) Botanical Surveys coast fawn lily NL/NL/2B.2 2 0.23 496 (Erythronium revolutum) Pacific gilia NL/NL/1B.2 4 0.40 1,263 (Gilia capitata ssp. pacifica) short-leaved evax NL/NL/1B.2 1 0.01 80 (Hesperevax sparsiflora var. brevifolia) Siskiyou NL/NL/1B.2 1 8.26 600 checkerbloom (Sidalcea malviflora ssp. patula) 1 Federal and State Codes: T = Threatened; E = Endangered; R = Rare; NL = Not Listed California Rare Plant Rank Codes and Threat Ranks: 1B Plants rare, threatened, or endangered in California and elsewhere. 2B Plants rare, threatened, or endangered in California, but more common elsewhere. 3 Plants about which more information is needed—a review list. 4 Plants of limited distribution—a watch list. 0.1 Seriously endangered in California 0.2 Fairly endangered in California 0.3 Not very endangered in California Coast Fawn Lily Coast fawn lily is not protected under the CESA or the ESA and is a CRPR 2B.2 species. Coast fawn lily is an herbaceous perennial plant in the lily family (Liliaceae) that occurs in northwestern California and northwards to southern British Columbia. This species grows on streambanks and other moist habitats in North Coast coniferous forest and broadleaved upland forest. Coast fawn lily flowers between March and July and generally occurs at elevations below 4,500 feet (ft.). Occurrences of coast fawn lily were found in coniferous forest habitat along the proposed gen-tie route near Bridgeville. The two coast fawn lily occurrences observed during 2019 botanical surveys occupy a total of 0.23 acre and contain an estimated 496 plants. Pacific Gilia Pacific gilia (Gilia capitata ssp. pacifica) is not protected under the CESA or the ESA and is a CRPR 1B.2 species. Pacific gilia is an herbaceous annual plant in the phlox family (Polemoniaceae) that grows in the coastal mountains of northern California and southern Oregon. Pacific gilia grows on steep slopes and open flats in coastal prairies, grassland, and dune habitats. This species flowers between May and August and generally occurs at elevations below 1,300 ft. Occurrences of Pacific gilia were found growing in grassland habitat on Monument Ridge. The four Pacific gilia occurrences observed during 2019 botanical surveys occupy a total of 0.39 acre and contain an estimated 1,263 plants. Short-Leaved Evax Short-leaved evax (Hesperevax sparsiflora var. brevifolia) is not protected under the CESA or the ESA and is a CRPR 1B.2 species. Short-leaved evax is an herbaceous annual plant in the sunflower family that grows on coastal bluffs and prairies in northern California and southern Oregon and is restricted to a relatively narrow band along the Pacific coast. Short-leaved evax flowers between May and August and generally occurs at elevations below 710 ft., although it occurs in the project area above 2,200 ft. One occurrence of short-leaved evax was found growing in grassland habitat on Bear River Ridge, near an occurrence documented in 2018. The one short-leaved evax occurrence observed during 2019 botanical surveys occupies a total of <0.01 acre and contains an estimated 80 plants. Siskiyou Checkerbloom Siskiyou checkerbloom (Sidalcea malviflora ssp. patula) is not protected under the CESA or the ESA and is a CRPR 1B.2 species. Siskiyou checkerbloom is an herbaceous perennial plant in the mallow family that grows in open coastal forests and prairies in northwestern California and southern Oregon. This species generally flowers between May and August and occurs at elevations between 50 and 2,890 ft. One occurrence of Siskiyou checkerbloom was located in grassland habitat on Bear River Ridge, near an occurrence documented in 2018. The one Siskiyou checkerbloom occurrence observed during 2019 botanical surveys occupies a total of 8.3 acres and contains an estimated 600 plants. CRPR 3 OR 4 PLANT SPECIES IDENTIFIED IN THE HUMBOLDT WIND ENERGY PROJECT AREA DURING 2019 BOTANICAL SURVEYS Stantec identified ten CRPR 3 or 4 plant species in the project area during the 2019 botanical surveys (Table 3). No CRPR 3 or 4 plant species were identified in the transportation route. The locations of all CRPR 3 or 4 plant occurrences found in the project area during the 2019 botanical surveys are shown in Figure 1.