Plants in the genus Cotoneaster (prounced co-to-ne-as-ter, not cot-on-easter) are very popular with north American gardeners, and not without good reason.  Cotoneasters are variable in form, from prostrate low-growing ground-covers, to tall arching shrubs, and may be evergreen or deciduous depending on species, making them very versatile in the garden.

Cotoneaster franchetii - friend or foe?

The genus name Cotoneaster is from the latin cotneum, meaning ‘quince’, and the suffix -aster meaning ‘imperfectly resembling’Cotoneaster franchetii was named specifically after the French botanist Adrien Rene Franchet (1834-1900).  This species, also known as Orange Cotoneaster, or Franchet’s Cotoneaster, is native to Southwestern China, Thailand, and Myanmar.

Cotoneaster franchetii is a fountain-shaped shrub capable of growing up to 3 meters in height, with oval 2-3 cm long broad leaves, that are shiny above, with dense hairs below.

Leaves of Cotoneaster franchetii are gloss green above...

..with dense white hairs below

The cup-shaped flowers appear in mid-spring, are pale pink in color, and are produced in small clusters called corymbs.

Numerous pale pink flowers are produced in spring

The berries appear in late summer, are small, 5-8 mm in diameter, and reddish-orange in color when mature.

At first glance Cotoneaster franchetii would seem to be an ideal habitat plant with its delicate spring blooms frequented by bees and butterflies, and the profusion of berries in fall and winter that are favored by birds.  However, all is not as it first seems.

Yellow-faced bumble bee (Bombus vosnesenskii) on Cotoneaster franchetii

Here in the Santa Cruz Mountains, and throughout northern and central coastal California, Cotoneaster franchetii is listed by the California Invasive Plant Council (Cal-IPC) as a moderately invasive pest species!

Cotoneaster franchetii is thought to have been introduced to California from China in the mid 1850s, soon thereafter escaping cultivation.  Although Cotoneasters grow well in manicured, fertile garden landscapes, in full sun to part shade, plants in this genus also do very well in our lean native California soils, thriving on dry sandy slopes, and serpentine soils.  Thus, once escaped from the garden they can run amok in our wild-land areas, displacing both native plant, and animal species.

Cotoneaster franchetii

Although our deer here do eat this species, sadly they don’t seem to favor it enough to aid in its elimination from the property, and even this shrub, that was heavily pruned by a grazing doe earlier in the season, has succeeded in setting fruit this fall.

 

Despite heavy deer damage in spring, this plant has still set fruit this fall, with each berry a potential new plant

Thus far we’ve noted two mature specimens of C. franchetii on the property.  Although one plant is close to the house, and might have been intentionally planted by the previous owner, the other specimen is in an undisturbed wild area of the property, and most likely a volunteer.  As this is the time of year when Cotoneaster is the most noticeable, with few species native here producing red berries this time of year, close scrutiny of our woodland understory plants should help us to locate any other rogues that are lurking amidst the shrubbery this winter.

Here Cotoneaster franchetii seems to favor growing in partial shade at the edge of our redwood groves

Berries are spread primarily by birds, but can also be distributed via waterways, so with two creeks on the property it’s important for us to ensure that this species is not permitted to grow along the creek banks to prevent its spread further downstream.

Cotoneaster franchetii - Curtis's Botanical Magazine c. 1914 (Public Domain Image)

Although for us C. franchetii is the species of the most concern here, other species of Cotoneaster are also invasive in this part of California, including Cotoneaster lactea, and the silverleaf Cotoneaster, C. pannosus.

Cotoneaster pannosus - Curtis's Botanical Magazine c. 1915 (Public Domain Image)

Removal is not as simple as cutting the shrub to the ground, as Cotoneaster species will produce numerous stump sprouts when cut.  Although small plants may be removed manually, larger specimens develop extensive root systems making complete removal difficult.  There are two recommended methods of removal for specimens of significant size. [1]

The first is to cut the shrubs close to the ground in late fall, and apply a concentrated herbicide to the stump.

The second recommendation is to cut the trunk to approximately one foot above ground level after fruit set (but before fruit fall), and then to anchor landscape fabric over the stump, and around the plant two feet in diameter, and leave the fabric in place for at least 12 months to minimize the likelihood of the shrub re-sprouting. The purpose of the fabric is primarily to reduce sunlight to prevent regrowth.  This second method, as it doesn’t require the use of herbicides, is the method of removal we’ll attempt this year to eliminate this species from the property.

Now is the perfect time to remove this plant, before the fruit starts to fall

If you live along California’s coast, Cotoneaster franchetii tends to thrive in the same areas favored by an excellent alternative, and native species, Toyon (Heteromeles arbutifolia), also known as Christmas Berry.  Toyon is also evergreen, produces delicate white blossoms in the spring to appease the bees, and large clusters of red berries in the fall, which are just as appealing to the birds.  Farewell C. franchetii, we’re replacing you with Toyon!

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[1] Cal-IPC Weed Workers Handbook Series – Cotoneaster Species (PDF)