Areas of historic fill now support upland forests populated by various species of trees. These trees make important den and nesting habitats for many animals.
The largest area of upland forest has developed on the fill east of the Lopas Channel. This forest canopy is dominated by cottonwood (Populus deltoides), silver maple (Acer saccharinum), and black locust (Robinia pseudoacacia) with common buckthorn (Rhamnus cathartica), glossy buckthorn (Frangula alnus), exotic honeysuckle (Lonicera sp.), and boxelder (Acer negundo) dominating the understory. This area provides nesting habitat for a variety of birds and mammals. American toads and garter snakes are often seen in this are of the Reserve. The fill provides natural cavities for both garter snakes and American toads to occupy and hibernate through the winters.
A second upland forest has developed on the south part of the parcel west of Lopas Channel. Dominant species in the canopy of this area include birch (Betula sp.), quaking aspen (Populus tremuloides), white poplar (Populus alba), cottonwood (Populus deltoides), black locust (Robinia pseudoacacia). The understory is predominantly common buckthorn (Rhamnus cathartica) white poplar (Populus alba), and red osier dogwood (Cornus sericea). Animal species associated with this area include river otter (Lontra canadensis), mink (Mustela vison), white tailed deer (Odocoileus virginianus), ground hog (marmota monax) and red fox (Vulpes Vulpes).
Honey bees that are managed on the property feed on many of these species of trees, especially black locust (Robinia pseudoacacia). Although it is considered an invasive species it has the benefit to not only the honeybees but also the rest of the native pollinators as well. Native shrubs are encouraged in the understory to also promote nectar and pollination sources.