Annona glabra aka Corkwood

Annona glabra, or pond apple, is in the custard apple family. This family bears the name Annonaceae. People also call it alligator apple and marsh corkwood. It is native to coastal Central and South America. Its range also spans Florida and the West Indies. It grows in warm, damp lowlands and mangrove swamps. These sites may hold brackish water, a mix with salt. The species has a wide range. Its status for risk of loss is Least Concern.

This tree grows fast. It keeps its leaves or sheds some as seasons change. Its usual height is about 10–26 feet [3–8 metres]. Some trees reach about 49–50 feet [15 metres]. The crown spreads to form a round shape. The trunk base may swell or form narrow buttresses. These are ridges that brace the trunk. The gray-brown bark forms shallow cracks and scaly ridges. Young twigs are glossy and reddish-brown. Leaves grow in turns along the stem, with smooth, unbroken edges. They are oval to egg-shaped, with a scent and leathery feel. Their tops are bright green; their lower sides are paler.

Single flowers are cream to pale yellow. Their sepals have pink bases. Beetles and other insects pollinate the flowers. The fleshy fruit looks much like a yellow-green apple. It turns yellow and gains a scent as it ripens in fall. The flesh is creamy-yellow and holds many light-brown seeds. People eat the pulp raw or make jelly and drinks. Fully ripe, soft fruit is best to eat. Its mild, sweet taste can seem bland. Yet fruit quality varies from tree to tree.

Pond apple grows best in full sun in humid tropical lowlands. It prefers moist sandy loam with a pH near 6. It can stand weeks of flooded soil and grows in salt marshes. It can bear brief, very light frosts near 32°F [0°C]. Gardeners grow it for its looks and its fruit. It copes with wet ground, so growers use it as rootstock for other annonas. Yet it can cause serious problems outside its native range. It has spread as an invasive tree where people introduced it. This includes parts of the Pacific.

People use its bark fibre and light, spongy roots. The roots can replace cork in floats and other items. Their pores mean they cannot seal bottles. People use the seeds to kill insects. Folk medicine uses leaves, stems, flowers, bark, and fruit for several ailments. These records show uses, not proof that the treatments work. Useful Tropical Plants lists no known hazards for this species. This does not prove that every plant part is safe.