7. Flatbush Avenue Entrace Area

Pumpkin Ash (Fraxinus tomentosa)

No Gourds on Board

You won't find any pumpkins growing on the pumpkin ash. Its name derives from the bulging, often gourd-shaped "butt" that develops at the tree's base for stability when it grows in wet terrain. Our specimen at BBG has a straight trunk because it is planted in relatively dry ground. This native tree is endangered in two U.S. states and is fairly rare in others, as it is extremely sensitive to drought and fire. Nevertheless, pumpkin ash is logged for use in the manufacture of wooden boxes and paper pulp. And since ash trees provide some of the highest-quality firewood, the pumpkin ash is also employed as a fuel wood.

All in the Family

It might seem strange that the pumpkin ash, which can grow up to 130 feet tall, is related to lilac and forsythia bushes. But all ash trees are part of the olive family (Oleaceae), along with more than 20 other types of plants, including jasmines and, of course, olive trees. These seemingly disparate plants are grouped together because botanists have determined that they all share broad similarities in their fruit and flower characteristics. The systematic placement of plants into related groups is known as taxonomy, and BBG has several taxonomists on staff. Often debated among scientists, taxonomic distinctions can now be made much more certain with DNA testing.

Notable Neighbors:

• 7A. Empress tree (Paulownia tomentosa)
• 7B. Black locust (Robinia pseudoacacia)
• 7C. Lavalle's cork tree (Phellodendron lavallei)
• 7D. Pin oak grove (Quercus palustris)

This pumpkin ash in Louisiana has developed a bulbous trunk in response to its swampy home. (Photo courtesy LSU AgCenter; Adam A. Agosta; LSU School of Renewable Natural Resources)