Liriodendron tulipifera Linnaeus, 1753

Elliott, Sara J., Grettenberger, Christen L., Donovan, Michael P., Wilf, Peter, Walter, Robert C. & Merritts, Dorothy J., 2016, Riparian and valley-margin hardwood species of pre-colonial Piedmont forests: A preliminary study of subfossil leaves from White Clay Creek, southeastern Pennsylvania, USA, Palaeontologia Electronica 13 (16), pp. 1-26 : 11

Liriodendron tulipifera Linnaeus, 1753

Figure 7

Material. EMS 425015 ( Figure 7.1-7.2 ), EMS 425014 ( Figure 7.3 ).

Description. Samara, elongate, tip mucronate, at the basal seed cavity curving upward and thickened, forming a ridge ( Figure 7.2 ).

Discussion. Liriodendron tulipifera (Tulip Tree) samaras superficially resemble those of various species of ash ( Fraxinus spp. ). However, ash samaras are flat and unridged, unlike those of L. tulipifera and the subfossils, which are curved and ridged ( Figure 7.2 ; McCutchen, 1977; Rhoads and Block, 2007).

Tulip Tree is native to the eastern half of the United States, with isolated populations in Texas. This species has a fast growth rate, and adult individuals typically reach 24-36 meters in height (Rhoads and Block, 2007; United States Department of Agriculture, 2011). Tulip Tree is considered to be a facultative-upland species. It grows well in moist, well drained, neutral to acidic soils and prefers mesic environments ( Beck, 1990). It cannot tolerate very wet or dry soils, is shade intolerant, and generally appears early in succession ( Beck, 1990; United States Department of Agriculture, 2011).

Figures

FIGURE 7. Liriodendron tulipifera (Tulip Tree). 1, Subfossil samara, EMS 425015; 2, Thickened ridge at basal attachment site of EMS 425015; 3, Mucronate samara tip from EMS 425014.