Fraxinus profunda
Fraxinus profunda, the pumpkin ash, is a species of "Fraxinus" (ash) native to eastern North America, primarily in the United States, with a scattered distribution on the Atlantic coastal plain and interior lowland river valleys from southern Maryland northwest to Indiana, southeast to northern Florida, and southwest to southeastern Missouri to Louisiana, and also locally in the extreme south of Canada in Essex County, Ontario. The pumpkin ash tree is native to swampland areas. It is a tree that is very important environmentally and economically. Currently, "Fraxinus profunda" is threatened by the emerald ash borer which is threatening  all species of ash trees in North America. The fruits of the pumpkin ash tree are also the largest of all ash trees in eastern North America. Taxonomy. The pumpkin ash tree is a member of the Oleaceae family, and has two synonyms "Fraxinus michauxii" Britton and "Fraxinus tomentosa" Michx. f. Benjamin Franklin Bush described the pumpkin ash in 1901. The pumpkin ash tree was erroneously hypothesized to be a fertile cross between "Fraxinus pennsylvanica" and "Fraxinus americana." This tree is also considered to be a hexaploid and has 138 chromosomes. Pumpkin ash was thought to be a cross between  Fraxinus pennsylvanica and "Fraxinus americana" because it shared similarities like abaxial leaf surfaces and how the bark develops as it becomes older. Despite the similarities, it was determined that "Fraxinus profunda" is a phylogenetically distinct species. The term pumpkin ash comes from the swollen trunk that can be found at the base of the tree. The other common names of "Fraxinus profunda" are red ash or swell-butt ash. Morphology. While normally a medium-sized deciduous tree reaching 12–30 m tall with a trunk up to 1 m diameter, the tree can reach 50 m tall with a 4.7 m  diameter trunk. The bark is gray, thick and fissured with a diamond pattern on mature trees. The winter buds are dark brown to blackish, with a velvety texture. The leaves are opposite, pinnate, with 7–9 leaflets; each leaf is 25–40 cm long, the leaflets 8–20 cm long and 5–8 cm broad, with a finely toothed margin; they are downy on the underside and along the rachis. The leaflets are stalked, with a short petiolule. Pumpkin ash trees are angiosperms meaning that they have flowers and fruits rather than seeds. The flowers are produced in panicles in spring shortly before the  new leaves; they are inconspicuous purplish-green with no petals, and are wind-pollinated. The fruit is a samara; it is the largest of any North American ash species, 5–8 cm long, comprising a single seed with an elongated apical wing 9 mm broad. "Fraxinus profunda" leaves have a very similar abaxial side as "Fraxinus americana." As the pumpkin ash tree grows and becomes older, the bark starts to become solid ridges that are continuous like the white ash. Like other species in the section "Melioides", "Fraxinus profunda" is dioecious, with male and female flowers produced on separate individuals. Ecology . This tree occurs primarily in swamps. Pumpkin ash is a food plant for the larvae of several species of Lepidoptera; see List of Lepidoptera that feed on ashes. It is also seriously threatened by the invasive Asian emerald ash borer. In 2017, the IUCN assessed the pumpkin ash as Critically Endangered, due to a massive population decline over most of its range due to the emerald ash borer. The emerald ash borer was first discovered in Michigan in 2002. The emerald ash borer attacks the phloem of the pumpkin ash tree. Within a six year period, the EAB can spread  quickly and move through local ash tree populations. The pumpkin ash tree is valuable economically and ecologically. Pumpkin ash trees are also susceptible to fire. Reproduction. Fruit production can begin as early as ten years of age. The seeds grow during the summer and are dropped in the early fall. As the seeds fall the most common type of dispersal is through wind, but with pumpkin ash trees growing it wet areas, the seeds can also be dispersed through the water and can survive wet conditions for months. As a seedling, it thrives in moist soils in openings in the  canopy cover. Dense cover does not benefit the young trees and it will grow very quickly in areas that are open with bare ground. Given highlight and moist conditions, the seedling will grow very quickly and can often outgrow other tree species. Distribution. "Fraxinus profunda" is a wetland and swamp tree. These wetland and swamp areas include land types such as tidal estuary swamps, depressions in coastal plains, floodplain flats, and coastal marshes. The range of the pumpkin ash tree tends to be discontinuous. Its native range is in the swamps and river bottoms as far south as northern Florida , and along the east coast up to southern Virginia. Few pumpkin ash trees can be found in southern parts of Illinois and Indiana, northern parts of Arkansas, and southern parts of Missouri. It has been extirpated from North Carolina, South Carolina, and Florida. Climate. Areas where pumpkin ash trees are found typically have an average rainfall of 40 inches to 48 inches of rain per year. During the growing season, from March to September, the average rainfall is around 26 inches. The temperature in areas with this tree average around 80 degrees F in northern states, and 82 degrees F  in the southern states. In the winter season, the average temperatures range from 35 degrees F in northern states and 60 degrees F in southern states. The pumpkin ash can tolerate temperatures as low as -24 degrees F. Soils. Pumpkin ash can grow in wetland soils, including anything from silt loam to clay loam. While pumpkin ash trees are found in moist and wet soils, they tend to grow slowest in these conditions, and they grow the fastest on the higher ridges of the swamp lands that drain more efficiently. Uses. Pumpkin ash trees provide resources for humans and animals  such as deer and birds. Birds, like wood ducks, feed on the fruit of a "Fraxinus profunda". Deer feed on the twigs and leaves of the pumpkin ash tree, and the humans use the woody parts of the tree as lumber for building. In addition to being used as lumber, the wood of pumpkin ash trees can also be used in tools such as stocks or handles. The wood can also be used as lumber, naval store products, and nursery stock products.