Platanus x acerifolia 'Bloodgood' (London planetree) is a hybrid cross between American sycamore (P. occidentalis) and Oriental planetree (P. orientalis). The original cross may have occurred as early as the 1640s, after which this tree became widely planted in London and other major European cities because of its perceived tolerance for urban pollution. City planting spread to America where this hybrid today is common in such distant locations as Brooklyn, New York and San Francisco, California. This hybrid can be very difficult to distinguish from its American parent. Distinguishing features include: (1) Leaves have deeper sinuses and (2) fruiting balls appear in pairs. Like its American parent, it typically grows as a single-trunk tree to 75-100 feet (less frequently to 120 feet) tall with horizontal branching and a rounded habit. Trunk diameter typically ranges from 3-8 feet. The signature ornamental feature of this huge tree is its brown bark which exfoliates in irregular pieces to reveal creamy white inner bark. Mature trees typically display mottled white bark that facilitates identification from great distances. The large 3-5 lobed medium to dark green leaves (4-9 inches wide) have coarse marginal teeth. In fall, foliage typically turns an undistinguished yellow-brown. Small, non-showy, monoecious flowers appear in small rounded clusters in April. Male flowers are yellowish and female flowers are reddish. Female flowers give way to fuzzy, long-stalked, spherical fruiting balls (to 1 3/8 inch diameter) that ripen to brown in October and persist into early winter. Fruiting balls appear in pairs. Each fruiting ball consists of numerous, densely-packed, tiny seed-like fruits (achenes). Fruiting balls gradually disintegrate as fall progresses, dispursing their seeds, often in downy tufts, with the wind. Also listed as Platanus hybrida and Platanus x hispanica. London planetree was originally thought to be much more resistant to sycamore anthracnose than its American parent, however this is no longer entirely clear since anthracnose resistance seems to vary considerably among various hybrid plants. Some reportedly resistant cultivars, such as ‘Columbia’ and ‘Liberty’, are available. Another disease problem of concern is cankerstain which can be fatal. Canker, leaf spot and powdery mildew may also occur. Insect visitors include borers, scale, Japanese beetles, caterpillars and mites. When grown as a lawn tree, litter from twigs, large leaves, bark and fruiting balls can pose significant clean-up problems.