14 Jan American Planetree
One of the most majestic of all the native trees in the landscape is the American planetree, Platanus occidentalis. In its native habitat the American sycamore is found in low-lying areas especially growing along rivers and streams. Its native geographic range is extensive. It can be found growing from Canada south to Florida and west to Minnesota and Texas. While in its native habitat it thrives in moist soils, it will grow in a wide variety of soils in the home garden.
At the Scott Arboretum we used to have a fantastic specimen below Sharples Dining Hall. This mature specimen had alabaster-white bark and towered over one hundred feet tall. After the death and subsequent removal of that large tree, we made sure to continue to represent this tree in our collections.
We added a young specimen in the lawn between Alice Paul and the train station. This area has never drained very well and tends to be water-logged. While most trees would not grow in these conditions it should be a perfect site for Platanus occidentalis.
American planetree is sometimes confused with the London planetree, Platanus x acerifolia which is the predominant shade tree along the Benjamin Franklin Parkway in Philadelphia. Platanus x acerifolia is a hybrid between P. occidentalis and P. orientalis. It differs from the American planetree in that the bark color tends to be more yellow than white.
The American planetree is susceptible to anthracnose which can make the leaves shrivel or, when the weather is especially wet, can cause the tree to prematurely defoliate. If this happens, the tree will often send out a new flush of leaves. Most of the time the effects of this disease are more aesthetic than causing long term detriment to the tree.
The leaves on the sycamore are a fairly large and can add considerably to the quantity of leaves raked in the fall. Also, the leaves have a fine fuzz or indumentum which can aggravate the eyes, skin and throats of some people.
In both its native habitat and in cultivation, the American sycamore is a favorite nesting spot for the Northern Oriole (syn. Baltimore Oriole). Locally, one of the very best specimens can be found in Sycamore Park in Lansdowne where there is a fantastic 300-year-old specimen.