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Products > Platanus racemosa 'Witness Tree'
Platanus racemosa 'Witness Tree' - California Sycamore

Habit and Cultural Information
Category: Tree
Family: Platanaceae (Sycamores)
Origin: California (U.S.A.)
Flower Color: Cream
Bloomtime: Not Significant
Height: 40-60 feet
Width: 40-50 feet
Exposure: Full Sun
Deer Tolerant: Yes
Irrigation (H2O Info): Low Water Needs
Winter Hardiness: 10-15 F
Platanus racemosa (California Sycamore) - A picturesque fast growing long lived California native deciduous tree that can grow to as tall as 100 feet but more typically is seen around 40 to 50 feet. The wide-spreading branches are often twisted or leaning with reddish-brown bark peeling off to expose the white wood underneath in a mottled pattern. Before fall the deeply lobed leaves turn brown sometimes staying on the tree until early spring. Plant in full sun to light shade and give deep, infrequent watering. It is cold hardy down to at least 10F and useful in USDA Zones 7 and above where it is drought tolerant once established in areas with a relatively high water table but otherwise will look best with occasional deep watering. It also tolerates heat and the smoggy conditions of our urban environments. Our native sycamore is a riparian species, found along streams at elevations below 4,000 feet from Shasta County down into Baja California. The name for the genus comes from the Greek name 'platanos' used for the oriental plane tree ( Platanus orientalis ) and the specific epithet is a reference to flowers being in racemes - these flowers occur in spherical clusters in late winter and spring and are not showy. It is an outstanding and beautiful natural looking tree in the garden but the pollen and fuzz of the leaves is also somewhat irritating and some are allergic to it, so best not used over heavily used patios. Because of the heavy leaf drop it is also difficult to garden under and often the understory is best left natural or with only a few durable plants. As a riparian species it is considered to be a phreatophyte and its roots will also seek water sources, so best planted a distance away from older sewer lines or other leaking water sources. The species is susceptible to the leaf blight called anthracnose that is caused by the fungus Gloeosporium plantani which cause several leaf and twig drop episodes in moist years in the spring, but rarely does permanent damage; this disease has been shown to have this association with this tree for as long as humans have known it, even found on plants in the fossil record. There has been recent concern about hybridization of our native sycamore with the non-native London Plane Tree (Platanus x acerifolia) with suspicion that some seed grown nursery grow might actually be hybrids. Our plants are cutting grown from an ancient tree that existed prior to the London Plane Tree being planted in California, the National Champion Platanus racemosa known as the Sister Witness Tree that grows along San Jose Creek in Downtown Goleta. It is listed as the National Champion on the American Forests Website and on the California Big Tree Registry This description is based on our research and observations made of this plant as it grows in our nursery, in the nursery garden and in other gardens that we have visited. We will also incorporate comments received from others and always appreciate getting feedback of any kind from those who have some additional information about this plant, in particular if this information is contrary to what we have written or if they have additional cultural tips that would aid others in growing Platanus racemosa 'Witness Tree'.