Increasing fruit production in wild populations of pawpaw (Asimina Triloba (L) Dunal) trees in southern Ontario

Abstract

The pawpaw (Asimina triloba (L) Dunal) is a unique native understory tree species found in the Deciduous and Carolinian forest regions in Southern Ontario. It is at the edge of its range in Ontario, most of the population exists in the United States in 26 of the eastern states. It is the only member of the tropical family Annonaceae to reside in North America and its large drooping leaves allow it to stand out in a forest setting. The pawpaw tree bears the largest fruit of any tree species in Ontario. The fruit is tropical in appearance and flavour. It is a food resource for both humans and wildlife. Studies conducted previously in pawpaw stands have noted that pollination and the subsequent fruit set have been low or non-existent. Although there is no concrete evidence suggesting why this may be, a loss of genetic diversity, habitat fragmentation and anthropogenic forces such as development may be contributing factors. This may be especially true for naturally occurring stands in Southern Ontario. Here, the pawpaw tree has a small population of wild trees. This species has high value and preservation through efforts such as habitat protection, increased genetic diversity through plantings, agroforestry, and even assisted migration could help to improve population numbers. This may help to increase pollination rates and fruit yields, allowing the pawpaw tree to continue its important role within the forests of Southern Ontario.