Adkins Arboretum’s Native Tree of the Year Program highlights the ecological and ornamental value of native trees to promote their protection in natural areas and use in cultivated landscapes.

2020 Native Tree of the Year: Paw Paw (Asimina triloba)

The best time to collect the fruit is after it falls from the tree, but before it hits the ground. Wise words for those hoping to find the perfect paw paw, the long-sought prize of the floodplain forest. Plucked too early from the tree, the paw paw is bitter and unpalatable. Left too long on the ground, the animals will happily munch on them for a tasty snack.

Paw paws generally ripen in September, though people seek them out in early spring and summer, monitoring the transition from the fuzzy brown flower buds to unique maroon flowers to a firm, powder-green fruit. Upon ripening, the fruit will drop and develop a leathery yellow-brown exterior. That's when it's in its prime. Also known as a custard apple, the paw paw has a flavor reminiscent of banana and mango. It also happens to be one of the last remaining tropical fruits native to the coastal plain.

Paw paws are easily distinguished in the forest. They prefer the floodplain, not too wet, not too dry, and they can tolerate some shade. They grow in colonies, dropping their fruit and setting their seed. With long, arching branches, the paw paw's leaves are distinctly tropical: large and obovate. In the fall, small clusters of fruit hang from the lush, leafy branches.

For those wishing to introduce this plant to their own landscape, it's best to do it when the plant is young or from seed, as larger trees don't transplant well. The seeds are relatively easy to propagate as long as they are properly stratified. Paw paws won't set fruit until they are 5 to 7 years old, but in the meantime, they provide excellent habitat. In fact, the paw paw is the only host plant for zebra swallowtail larvae. Foxes, raccoons, squirrels, and insects all indulge in the paw paw fruit. The paw paw plant itself contains natural insecticidal compounds called acetogenins, which tend to protect the plant from rabbit and deer browsing and protect the zebra swallowtail butterfly from predators.

The paw paw fruit has risen in popularity and is now the sole focus of many local festivals and farmers markets. The demand is certainly there for paw paw fruit to be offered on a commercial scale, but the shelf life of a paw paw is short at best. While growers are experimenting with various cultivars that produce bigger, longer-lasting fruit, perhaps these fruits are best plucked from the ground and eaten while immersed in the beauty of the forest.

Trees previously named Adkins Arboretum Native Tree of the Year include Liriodendron tulipifera (American tulip tree, 2011), Quercus alba (white oak, 2012), Magnolia virginiana (sweetbay magnolia, 2013), Fagus americana (American beech, 2014), Cercis canadensis (Eastern redbud, 2015), and Juniperus virginiana (Eastern red cedar, 2016), and Sassafras albidum (sassafras, 2018).

- Kathy Thornton, Land Steward