Pawpaw

(Asimina triloba [L.] Dunal)

Description 

Asimina triloba is a member of the tropical custard-apple family (Annonaceae).  It is a small to medium size tree usually growing 15 to 20 feet tall but can grow up to 40 feet⁹.  The common name is derived from that of an indigenous  South American name for  the unrelated papaya¹⁰. The leaves of the pawpaw are large ( up to 12 inches), alternate and oval-shaped.  Leaf size decreases down the stem.  April blooming in Maryland, pawpaw has  beautiful, deep red or purple flowers with  three petals on the inside and three sepals on the outside. Flowers are about 1.5 inch across.  The putrid-smelling flowers are likely pollinated by flies and beetles¹⁰.  Pawpaw produces a large, sweet green fruit similar in appearance to a mango and similar in taste to a banana.  The fruit is technically a berry and is the largest on any tree in North America⁹.

Pawpaw tree⁹.

Pawpaw flower, @ J. Gallagher².

Ripe pawpaw fruits, @ A. Shaw¹¹.

Distribution 

Pawpaws are native to the United States and can be found in warmer environments from the Gulf Coastal plains to the Great Lakes and even in some parts of England¹.   Pawpaws prefer weather conditions that are hot in the summer and cold in the winter with high humidity¹. They  can grow well in the shade. Pawpaws also prefer well drained, slightly soils¹. Except for Garrett County, pawpaws can be found throughout  Maryland¹³ along riversides, moist woodlands, and even on some farms².

 

 

 

 

 

 

 

 

 

 

Distribution of pawpaw, Wikimedia Commons¹².

Wildlife importance 

Asimina triloba is an important part of their ecosystem because their fruit provides food to many wildlife such as birds and mammals⁷.  Zebra Swallowtail butterfly larva eat the leaves.  The fruits are eaten by black bears, raccoons opossums, deer, foxes and squirrels².  

Economic importance 

Pawpaw is a potential crop species, but has not yet been developed.  It has potential over a broad climatic range and the fruits have nutritional value.  Additionally, the wholesale and nursery market for plants is great¹⁴.

 Threats 

The pawpaw peduncle borer is the only known pest, and it is relatively rare.  The larvae of this moth bore into the flowers and prevent successful fruit set⁸.  

 Interesting facts 

• Pawpaw seeds, barks, and leaves can be used to make home remedies for alternative treatments that can help reduce fever, vomiting, inflammation and vomiting³. 
• Every third Thursday September it is national Pawpaw Day where people celebrate the fruit by going to farms or markets to buy and taste⁵.   
• Pawpaw is the state fruit of Ohio¹¹, and there  is an annual Pawpaw festival held in Albany, Ohio by the Ohio Pawpaw Growers Association that is held on National Pawpaw Day⁶.  
• An American folk song describes picking the fruit².

Where, oh where is dear little Nellie?
Way down yonder in the pawpaw patch
Pickin’ up pawpaws, puttin’ ’em in your pocket

References 

1. Blossum Nursery: Pawpaw habitat and climate 
2. Maryland Grows–Pawpaws: the tropical fruit from our forests
3. RxList: American pawpaw
4. University of Georgia Extension.  Minor Fruits and Nuts in Georgia
5. National Day Calendar:  National Pawpaw Day
6. Ohio Pawpaw Festival
7. USDA, Forest Serviced Fire Effects Information System:  Asimina triloba  
8. Purdue University Cooperative Extension Service, Growing Pawpaws
9. University of Kentucky, College of Agriculture, Food and Environment:  Pawpaw
10. Peterson Pawpaws:  Pollination
11. Metro Parks, Westervile, Ohio:  Pondering pawpaws. 
12. Wikimedia Commons, Asimina triloba range map
13. Maryland Plant Atlas: Asimina triloba
14. Purdue University, Horticulture:  Pawpaw

Contributed by J. C. Youn 

 Towson University Glen Arboretum