One of the main goals of our Central Park Flora project is to document which species of plants are not only living and surviving in Central Park, but reproducing. For trees, this means finding seedlings. You can have large, beautiful trees, but if the habitat is not conducive to seedlings, the future of our native species will not be guaranteed. As the condition of the Park deteriorated in the '60s and '70s, trampling compacted soil to the point where many seedlings were unable to regenerate. During the years that I worked for the Central Park Conservancy, one of the most satisfying accomplishments was seeing the benefits of improved soil. In areas where we loosened compaction, added compost and provided protection from trampling, oak seedlings, as well as other species began popping up! The two images below show red oak seedlings in the North Woods. We saw many healthy seedlings.
The image below shows bud scales still attached to this red oak seedling. Bud scales protect the developing embryonic leaf until it finally emerges in the spring.
This next seedling is a honey-locust, Gleditsia triacanthos. Honey-locust is native to central North America but has become common in our area. It is a commonly planted street tree.
Anyone familiar with our oak trees, might not recognize this as an oak, the shape of the leaf is unusual. This is a willow oak, so-called because the leaves look more like the leaves of a willow tree. There are several large specimens in the Ramble near the Boathouse and many seedlings were emerging in the surrounding area.
Ginkgos are an interesting case when it comes to seedlings. We see areas with many small seedlings, but we have not found any juvenile trees. We are not sure why they don't seem to survive to adulthood.
Another non-native we have seen reproducing is the goldenrain tree. This is an Asian species planted for ornamental purposes. The second photo below shows the interesting lantern-shaped seed pods on the parent tree. We have been finding seedlings wherever we find an mature tree. Will this eventually be invasive?
This next species is no surprise to find anywhere in the Park. It is one of our worst invasives -the Norway maple. This species has been widely planted as an ornamental and shade tree. It leafs out earlier than our native trees, casting shade that prevents our woodland wildflowers from growing. It keeps its leaves longer in the fall, giving it an advantage over our native trees. It out-competes many of our native species and forms monocultures. The Conservancy has had good success with manually removing young Norway maples on a regular basis. In the North Woods, this removal of Norway maples has allowed one of our loveliest natives to flourish, the trout lily.
Despite being one of the most common trees in the U.S, the silver maple, a native of our area, is not common in Central Park. It is a wetland species that is tolerant of a wide range of growing conditions. It grows quickly, but has a shallow root system and brittle wood, therefore is easily damaged in storms and so it is not really a good choice for urban parks or as a street tree. We found one large specimen near 110 street on the west side. There were seedlings growing around the parent tree. The very deeply-lobed leaves make this species easy to identify.
My favorite native maple, the sugar maple does well in Central Park as long as the Norway and other weed trees are kept under control. Here are sugar maple seedlings flourishing in the Hallett Nature Sanctuary in the south end of the Park. Notice that the leaves are not as finely lobed as the silver maple. This species turns beautiful orange to red colors in the fall. This fall, head up to the south side of the North Meadow ballfields area, where there are several mature specimens, to see a spectacular display of color!