Liriodendron 65 



LIRIODENDRON TULIPIFERA, Tulip Tree^ 



Liriodendron tulipifera, Linnseus, Sp. PI. ist ed. 535 (1753); Loudon, Arb. et Frut. Brit. i. 284 

 (1838); Sargent, Silva of N. America, i. 19, tt. 13, 14 (1891). 



A lofty tree, attaining in America in the most favourable conditions a height of 

 190 feet, and a stem diameter of 10 feet. Bark grey and smooth in young trees, 

 becoming darker in colour and furrowed in old trees. Roots, fleshy with pale brown 

 bark, having an aromatic odour and pungent taste. 



Leaves extremely variable in shape, but generally saddle-shaped or lyrate in out- 

 line, with a rounded or cordate base, and a truncate emarginate apex,^ the midrib 

 being prolonged into a short bristle. Sometimes they are quite entire, but are more 

 usually lobed, the lobes varying from 2-6 or even 8 in number, and often ending in a 

 point. Venation pinnate. The leaves are 3-5 inches in length and in breadth, dark 

 green and smooth above, lighter in colour and minutely pubescent underneath. 

 Stalks about as long as the blades, angled and slender, so that the leaves quiver with 

 any movement of the air. In autumn they turn bright yellow in colour, and give the 

 tree a handsome appearance. 



Two lateral stipules ' occur on the twigs, attached a little higher up than the 

 insertion of the leaf-stalk. These are the scales which have formed the buds of the 

 previous winter ; and, as a rule, they shrivel up and fall off when the young leaves are 

 fully matured ; but some of them remain on vigorous shoots till late in summer. 



The flowers resemble a tulip in shape, being \\-2 inches long, with a width of 

 2 inches at the summit. The petals are greenish white, with an orange-coloured 

 band at the base, which secretes nectar attractive to bees. These visit the trees in 

 myriads in May, the flowering season in Illinois. 



The fruit, light brown in colour, is a cone made up of a large number 

 (about 70) of ripe carpels, which consist of a 4-ribbed pericarp surmounted by a 

 flattened woody wing (the enlarged style). The wing may carry the seed by 

 currents of air 300 or 400 feet from the parent tree. The carpels remain on the tree 

 till thoroughly dry, some usually persisting throughout the winter on the receptacle, a 

 few falling at a time as the wind dislodges them. The outer ones are nearly always 

 sterile. The carpels will float in water for nearly a year without sinking ; and this 

 may explain the distribution of the tree along the banks of rivers. The seed has a 

 fleshy albumen, in the summit of which is situated a minute embryo. 



Seedling. The seedling has two aerial short-stalked oval cotyledons about 



' Usually called " Yellow Poplar " in the United States, " White-wood " also being a name in use amongst the western 

 lumbermen. 



' Lubbock, in Trans. Linn. Soc. (Bot.) xxiv. 84, ascribes the form of the leaves to the way in which they are packed in 

 the bud. 



^ Occasionally the stipules are attached as wings to the leaf-stalk either near its base or higher up ; and in rare cases they 

 even unite with the base of the leaf-blade, appearing then to be extra lower lobes of the leaf itself. For accounts of these 

 peculiar stipules and remarkable forms of leaves occurring in tulip trees, see E. W. Bury in Bull. Torrey Bot. Club, 1901, 

 p. 493, and in Torreya, 1901, p. 105, and 1902, p. 33. 



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