Updated: Oct 23, 2021
There is potential with this native plant! Today, landscape architects seek opportunities to utilize native species wherever they practice, but in California, the natives can be temperamental. Case in point, Acer circinatum is a beautiful maple with brilliant fall color. Easily mistaken for Japanese maples, vine maples (we'll discuss this common name in a moment) could easily reside in an Asian-inspired garden while performing double duty contributing to the native landscape. The caveat to their performance is, however, dependent upon their sun exposure and care that might be ignored if using hardier forms of Japanese maples. For example, we planted one in our home garden, adjacent to a sapling coast live oak that we're encouraging to grow. We thought the oak would have provided shade by now, but it has not expanded its width to protect the maple from sun. Combined with well drained soil and reduced watering schedules (in support of the oak and drought), I now see we will need to move the little maple to a shadier, wetter part of the garden. Here's what you need to know:
Vine maples are native to drippy forested areas from British Columbia to Northern California. This should tell you that they need a similar microclimate: moist, shady, with a well-composted soil.
The level of shade changes how they grow. In more light, vine maples will remain compact or even shrubby, lending them to a Japanese maple appearance. Too much sun will fry the leaves, particularly in Autumn when the Diablo Winds blow. Conversely, and this is where the common name comes in, deep shade will prompt more vine-like habits, crawling against another tree upward towards light.
Unlike Japanese maples that can tolerate full sun (but not necessarily perform well), A. circinatum depends on shade, particularly in the afternoons if not all day. This last need is critical for landscape designers to understand. If the design specifies an overstory canopy tree, make sure that tree is already providing shade on the day of planting the maple. Otherwise, this understory tree will suffer with poor performance.
Providing A. circinatum with the right conditions for growth will reward designers with reliable performance and fall color. Nurseries have made it more readily available as either a tree or a multi-trunk shrub. If the right conditions are provided, this maple is an excellent specimen for the autumnal season.
West Valley College Campus Location: Acer circinatum 'Pacific Fire'
Science & Math (north face).
Long: 122° 0'35.14"W
All other photos: Late fall after hot sun toasted the foliage. Note the red stems that will persist over winter, which look striking against the masonry wall. Leaf detail: Collected from our sad little specimen at home.
Botanical Name: Acer circinatum
Acer: Traditional Latin name for maple
Circinatum: Refers to the overall round form of the leaf despite its lobes
Common Name: Vine maple
Family Name: Sapindaceae
Origin: Native - British Columbia to Northern California
Positioning: Forest understory/woodland, riparian corridors, container
Garden Themes: Shade, winter, autumn, native, Asian-inspired, water, rain
Uses: Multi-trunk: shrubby specimen; standard: small specimen, accent, green stormwater infrastructure (not recommended for C.3 soil specifications).
Type: Deciduous tree or large shrub
Form: Varies based on location, from low and spreading to vase, rounded or vine-like
Size: 10' to 25' wide x 10' to 25' tall
Outstanding Feature(s): Fall color (leaf), winter interest (bark), flexible uses
Bark: Green when young turning gray with age. New growth exhibits red-brown tint. A. circinatum 'Pacific Fire' has striking red stems for winter interest.
Shape: Palmate, lobed
Margin: Irregularly serrate to doubly serrate
Color: Medium green turning red/orange/yellow in autumn.
Surface: Slightly hairy
Flower: Spring. Flowers are tiny but in noticeable clusters, from 3-6 with pronounced stamens, red sepals, and greenish-white petals.
Fruit: Autumn. Samara, deep red when mature
cultural requirements, tolerances & problems
Sunset Zones: A3; 2b-6, 14-17
USDA Zones: 4-7
Light: Partial shade to full shade (avoid afternoon sun)
WUCOLS SF Bay Area Hydro Zone: Moderate
Texture: Sand, Loam, well-composted
Moisture Retention: Moist but well-drained
pH: Slightly acidic to alkaline
Problems: Can be weedy in riparian corridors
Branch Strength: Medium
Disease: Verticillium, root rot, armillaria
citations & attributions
Norris Brenzel, K. (Ed.). (2012). The New Sunset Western Garden Book. New York: Time Home Entertainment, Inc.
NC State Extension. "Acer circinatum." North Carolina State University, Raleigh. Accessed on June 27, 2021, from https://plants.ces.ncsu.edu/plants/acer-circinatum/.
Urban Forest Ecosystems Institute SelecTree. "Acer circinatum Tree Record." 1995-2021. Cal Poly State University, San Luis Obispo. Accessed on June 27, 2021. https://selectree.calpoly.edu/tree-detail/45.
Water Use Classification of Landscape Species. "WUCOLS IV Plant List." University of California, Division of Agriculture and Natural Resources, Davis. Accessed on June 27, 2021.