Camilla Cook: Tree Inventory Update #2

Since my last blog post, I have completed fieldwork for Block 1-5, which can be referenced in the map given in this post. Even though we have surveyed Helen S. Faison Arts Academy school, we are still having trouble identifying if the school has American Sycamore or its cultivated version, London Planetree in and around their property. The only differentiating factor between the two species are their fruit — American Sycamore’s fruit hang individually whereas London Planetree’s fruit hangs in pairs. Since London Planetree can mimic American Sycamore when fruit fall, I am in contact with Operation Better Block and the school to help identify the right tree species there.

Block 1 and 2 had a mix of different tree species – Ulmus rubra (Slippery Elm), Gleditria triacanthus inermis (Thornless Honey Locust), Celtis occidentalis (Hackberry), Zelkova serrata (Japanese Zelkova), and Quercus alba (White Oak). The most standout part of the fieldwork that day was that almost all if not all the Ulmus rubra trees were infected by insects and had tremendous insect galls on their leaves. In comparison, Celtis occidentalis is in the Elm family and those trees were in good condition – indicating that these elm species have varying resistance to insect disease. I plan on researching what type of insect or disease is affecting the Ulmus rubra trees in South Homewood.

Block 3 had no street trees.

*Identification of insect ridden elm species might change. Noticed the underneath part of a collected leaf vs. images of insect galled leaves are a different pattern.

Update (July 9th) — I have realized that the Celtis occidentalis (Hackberry) are the leaves below that are infected with the insect galls. Hackberries are in the Elm family, which supports my theory that a certain type of insect or disease is infecting (non-native) trees in the Elm family.

Insect galls on leaves

Ladybug on a leaf

Potential insect damage on a bark

Thornless Honey Locust leaves

These leaves are damaged as well.

Leave a Reply

Your email address will not be published.