Learn The What and Why of Our Fall Plantings
By Varian Bosch, FOW Field Operations Manager
Fall in the Wissahickon not only brings cooler weather, but for Friends of the Wissahickon (FOW) it also brings planting season. Throughout the year (and the previous year) we are constantly clearing invasive species to make room for our native trees and shrubs. We do this to promote our native ecosystems and the wildlife that live within.
Every year, FOW plants over 400 native trees and shrubs with the help of our volunteers. Plants are affected by a million and one things, and all these factor into the success rate of our plantings. When choosing the correct plant species for a location, we look at many different factors, including, but not limited to, the location (upland vs riparian), water and sun needs, soil type, and most importantly, ecosystem benefits. Once these factors are considered, a species list for an area is created.
We want our plants to not only live for the next 10 years, but to create an ecosystem that will survive for hundreds of years to come. Ideally, FOW would plant all native species, but sometimes we have to expand our range a little to include plants that will withstand changing weather patterns and rising temperatures caused by climate change.
If you would like to support projects and programs like our large-scale plantings, we urge you to become a member. Your membership donation makes a huge impact on our ability to continue to grow and foster a thriving urban tree canopy.
The following are a few of the special species that meet our criteria that we’ll install at our October service days. I hope you’ll join us by registering on our events calendar.
Photo: Katja Schulz via bplant.org
Scarlet Oak (Quercus coccinea)
Philadelphia is on the northern edge of Scarlet Oak’s native range. It has historically been found north of us, but it is much more rare and is much more common further south. With climate change, the forecasts are showing that Philadelphia will have a climate much closer to that of the Carolinas, close to the center of the Scarlet Oak’s native range. Oak species are considered one of the most valuable trees in an ecosystem. This is because it has habitat value for hundreds of species of insects, which in turn creates a food source for many species of birds and mammals in the food chain. Oaks also have very strong root systems, which are vital in a steep gorge environment like the Wissahickon. The Scarlet Oak is only one of the species of oak that we regularly plant here in the Wissahickon.
When choosing this species for a planting, this species is good in upland areas that have high clay content and acidic soils. They can do well in both partial shade and full sun as they are growing to take over as a canopy and shade tree. They can also do well with occasional droughts and are slightly deer resistant.
Photo: Katja Schulz via bplant.org
Sugar Maple (Acer saccharum)
Sugar Maples are a staple of the ecosystem in the Northeast. They are well known for being the source for maple syrup. We do not normally tap our trees here in the Wissahickon, but the Wissahickon Environmental Center does have their maple syrup demonstrations in late winter. Sugar Maples have a high habitat value for many different insects and birds. They are also of high value for holding carbon and preventing soil erosion with their roots. Along with all of these ecosystem values, they are also beautiful in the fall when their leaves change color all along the Wissahickon Creek.
When choosing this species for planting, we want to look for a location that is upland with full sun or partial shade, has a high clay content with a high amount of organic soil, has slight acidity or neutral soil pH, and has good drainage or in soils that retain moisture. Sugar maples also have a slight resistance to deer.
Photo: Wendell Smith via. iNaturalist
Pawpaw (Asimina triloba)
Pawpaws are native to much of the eastern US. Their habitat value is very specific, but it is an exclusive home to the Zebra Swallowtail Butterfly. They also produce fruit that can be eaten raw or cooked. The fruit has a custard-like texture with flavors that have been described like a combination of a banana and mango. It is like a tropical fruit that grows in colder temperatures.
This plant grows in wetter conditions, though are not good in conditions that are always wet. They are usually found closer to water and can be found in conditions that range from shade to full sun, though they usually need full sun to produce fruit. They are resistant to deer and many of the insect pests that are common in this area.