What Mistletoe Is
Eastern mistletoe (Phoradendron leucarpum) is a hemiparasite — it grows partially embedded in tree branches, extracting water and some nutrients from the host, while also photosynthesizing its own food. It's native to North Florida and common on oaks, red maples, and other deciduous trees throughout the region.
You've seen it: the dense, rounded clumps of evergreen foliage visible in deciduous tree canopies in winter when leaves are down. It's also the mistletoe used in holiday decorations.
Does Mistletoe Harm Trees?
Yes, but usually slowly. Because mistletoe draws water and some nutrients from the host tree, heavy infestations create measurable stress — particularly during drought. A tree with numerous heavy clumps scattered throughout the canopy is being taxed in ways that affect growth and can weaken response to other stressors.
The impact depends on:
Infestation level. One or two clumps on a large tree has minor impact. Many clumps throughout the canopy is more significant stress.
Tree health. A vigorous tree in good growing conditions handles limited mistletoe well. A tree already stressed by drought, root problems, or disease is more vulnerable to the cumulative effect.
Location in the canopy. Mistletoe on minor branches has less impact than mistletoe that has established on major scaffold limbs or near the trunk.
When Does It Become a Problem?
Heavy infestations on stressed trees: Oaks that are already declining, or trees in areas affected by drought, root zone compaction, or disease, face greater risk when mistletoe adds additional draw on their water and nutrient resources.
Structural issues at attachment points: In some cases, heavy mistletoe growth can weaken branch attachment points over time. A large, heavy mistletoe clump on a branch that's already structurally marginal creates additional load.
Removing Mistletoe
Mistletoe removal is possible but not permanent. The haustorial root system (the embedded root-like structure) penetrates into the branch — removing the visible clump doesn't eliminate the haustorium, and regrowth is common.
Pruning the host branch is the only reliable removal method — cutting the branch below where the mistletoe has embedded removes both the visible clump and the haustorial connection. Whether this is appropriate depends on where the branch is in the canopy and how structurally significant it is.
Cutting the visible clump reduces the load and photosynthetic contribution but doesn't eliminate regrowth.
For significant infestations on valuable trees — particularly stressed or high-value specimens — a professional assessment identifies which clumps represent meaningful risk and whether removal of host branches is appropriate given the tree's overall structure.
Live Oaks and Mistletoe
Live oaks in Tallahassee commonly carry some mistletoe. In most cases, moderate mistletoe on a healthy live oak is a cosmetic concern more than a health threat. The live oak's vigor and longevity means it can tolerate what would stress a shorter-lived species more readily.
That said, live oaks that are already under stress — construction-related root damage, drought, root rot — with heavy mistletoe infestations are a combination that warrants attention.
Questions about mistletoe or tree health on your North Florida property? Call (850) 570-4074 or request a consultation online.