2021 Zoya Akulova 2021 Mike Russler 2021 Mike Russler 2017 Adam Chasey 2006 Steve Matson 2021 Mike Russler 2021 Mike Russler 2021 Mike Russler 2017 Adam Chasey 2001 David Graber 2021 Mike Russler 2019 Susan McDougall 2012 Aaron Arthur
Arctostaphylos densiflora is a shrub that is native to California, and endemic (limited) to California.
California Rare Plant Rank: 1B.1 (rare, threatened, or endangered in CA and elsewhere).
State of California status: Endangered.
[Wikipedia] Rarity, Pathogenic Risk, Description: Arctostaphylos densiflora, known by the common name Vine Hill manzanita, is a very rare species of manzanita. It is endemic to Sonoma County, California, where it is known from only one extant population of 20 to 30 individual plants. These last wild members of the species are on land near Sebastopol which is owned and protected by the California Native Plant Society. In addition, there are five to ten plants of this manzanita taxon growing on private property about a mile away. The local habitat is mostly chaparral on sandy shale soils.
The entire wild population is infected with the root pathogen Phytopthera cinnamomi and subject to mortality, which could result in species extinction.
Plants have been propagated through a collaborative effort by California Native Plant Society (CNPS) volunteers at the Vine Hill Preserve and the CNPS Nursery located at the Laguna de Santa Rosa Foundation near Santa Rosa, California. The purpose of the effort is to outplant to establish healthy genetically diverse plants at several locations other than the Vine Hill Preserve.
Locations as of May 2023 with outplanting of disease free manzanitas include the Pitkin Marsh Preserve and Cunningham Marsh Preserve in Sonoma County. Others include Regional Parks Botanical Garden Tilden, the University of California Berkeley Botanical Garden, the San Francisco Botanical Garden, the University of California Santa Cruz Arboretum, San Francisco State University, the Mendocino Coast Botanical Gardens, and the northern most outplanting at the Humboldt Botanical Garden with six of the 20 genetic lineages.
Arctostaphylos densiflora is a small shrub growing in low, spreading clumps under one meter in height. Of the heath family, its shiny green leaves are oval to widely lance-shaped and less than three centimeters long. It bears inflorescences of light to bright pink urn-shaped flowers. The fruit is a drupe about half a centimeter wide.
The flowers of this species provide nectar for butterflies and native bees in the spring, berries provide food for birds in the late summer, and the low-growing habit of the plant make it a good home for California valley quail and wrentit nests. (Lowe 1999)
Roadside banks and neighboring areas in chaparral habitat with acid marine sand (York 1987).
A. densiflora likely appeared about 1.5 million years ago, although the Arctostaphylos genus itself arose in the Miocene era. (contributed by Mary Ann Machi)
/app/up/entry/277/th/83113.jpg:!/app/up/io/137/th/io41312-0.jpg:!/app/up/entry/254/th/76203.jpg:!/app/up/mg/119/th/mg35735-1.jpg:!0000 0000 0306 1339:!/app/up/entry/254/th/76206.jpg?a:!/app/up/entry/254/th/76205.jpg:!/app/up/entry/254/th/76204.jpg:!/app/up/mg/119/th/mg35735-2.jpg:!0000 0000 0302 0094:!/app/up/io/137/th/io41311-0.jpg:!/app/up/entry/82/th/24790.jpg:!0000 0000 0612 0736:!
2021 Zoya Akulova:!2021 Mike Russler:!2021 Mike Russler:!2017 Adam Chasey:!2006 Steve Matson:!2021 Mike Russler:!2021 Mike Russler:!2021 Mike Russler:!2017 Adam Chasey:!2001 David Graber:!2021 Mike Russler:!2019 Susan McDougall:!2012 Aaron Arthur:!
Information on California plants for education, research and conservation,
with data contributed by
public and private institutions and individuals.
[web application]. 2023. Berkeley, California:The Calflora Database
[a non-profit organization].Available: