Mistletoe's Effect on Trees in an Urban Landscape

Presenter: Katarina Jackson

Co-Presenter(s):
Jessica Juarez, Josalyn Lopez

Presenter Status: Undergraduate student

Department: Biology

Screenshot URL: https://drive.google.com/uc?id=102G8Xh1-l8G06NkbHCvZrXh559h7c40Q

Abstract:
Mistletoe is a parasitic plant that grows on tree branches and steals nutrients and water supply from the trees that it infects. As mistletoe plants grow on their host trees, they may slowly kill their host because it does not get the nutrients it needs to survive. For land managers, it is important that they know how this can impact their land, but it is not known how mistletoe impacts trees in an urban landscapes. This project involves assessing three different urban landscapes in Northern California for the frequency of mistletoe in these areas. The methods for our research included measuring 30 trees that were at least 6 m in height, with a visible crown, and categorized as small (6-8 m), medium (9-12 m), or large (> 12 m). In addition, mistletoe density level was categorized as small (small scattered plants), medium (larger plants), or large (large cluster of mistletoe). The species of the trees were also recorded. We assessed mistletoe infection level in Modesto (park), Lake Temescal (recreational area), and Point Richmond (park). The results have shown that all three areas were hosts to mistletoe, although there is no relationship between the host trees and the tree size, but we did find that there might be a relationship with the leaf density and the spacing between trees. Mistletoe seems to be more common on the trees with thicker leaves. These results show that land managers should be concerned about mistletoe because it is imperative to the tree’s survival.