(Gyrocarpus americanus)
Gyrocarpus americanus is a flowering plant in the Hernandiaceae family, with a wide pantropical distribution. Its common names include the helicopter tree, propeller tree, whirly whirly tree, stinkwood or shitwood. Gyrocarpus americanus is a slender, deciduous tree with smooth, grey bark. The tree grows to about 12 m in height. The leaves are spirally arranged, crowded near the ends of the branches, and grow up to 150 × 120 mm in size. They are ovate, often 3-lobed, dark green above, paler and greyer below, with velvety surfaces, 3-veined from the base. The veins are yellowish. The cream to yellowish-green flowers grow in compact heads and have an unpleasant smell. The fruit is a woody nut with two long thin wings that help in wind dispersal. The winged fruit and the smell of the flowers have given the tree its various common names.