American Tree Experts

3 Common Parasitic Plants That Are Harmful For Trees

Learn to protect your tree treasures – A guide to recognizing and defeating 3 common parasitic plants

While most plants get their energy through photosynthesis, a few take a more cunning approach and steal their nutrition from other plants. Around 4,000 species of flowering plants have embraced parasitism as their survival mechanism. Read on to learn about parasitic plants that can harm your trees.

Harmful Parasitic Plants

  • Trees are an essential component of our natural landscapes, offering numerous benefits, from providing shade fruits to enhancing the overall aesthetic appeal of our surroundings. However, they face potential harm from parasitic plants that often go unnoticed. Failure to identify and eliminate these intruders can result in severe damage, hindering a tree’s growth and making it susceptible to diseases, pests, and structural failure.

Parasitic plants are incapable of producing essential nutrients independently. They latch onto other vegetation, particularly trees, to sustain themselves. Many lack chlorophyll, the crucial element for photosynthesis, making them reliant on healthy trees for essential nutrients. Therefore, identifying the presence of parasitic plants becomes crucial.

Let’s discover some of the most prevalent parasitic plants to help you identify and address these threats to ensure the well-being of your trees.


  • Dodder, also known as Cuscuta californica, is a distinctive twining plant belonging to the Morning Glory family. Commonly referred to as chaparral dodder, this species typically displays a light orange-brown hue. Its unique appearance is often similar to spaghetti or silly string, characterized by a dense mass of vining stems.

Dodder cannot produce chlorophyll and has no typical green coloring. It extracts nutrients from its host plants. It can quickly proliferate without proper management, enveloping entire canopies and compromising the health of the host tree. This unchecked growth weakens the tree and renders it susceptible to other pests, parasites, and diseases.

Oak Mistletoe

  • Oak mistletoe, scientifically known as Phoradendron leucarpum, is a prevalent parasitic plant frequently found on numerous trees. The term “phoradendron” refers to “tree thief” due to the plant’s parasitic nature. It exhibits a distinctive appearance resembling green balls or clusters of leaves on tree branches. Oak mistletoe can grow into unsightly masses, reaching three feet tall. It poses a serious threat to the health of your tree.

This parasitic plant can affect over 100 different tree species, with a particular fondness for oaks. Oak mistletoe extracts nutrients and water from the host tree, gradually weakening it. If you detect any growth indicative of oak mistletoe, contacting an arborist for professional maintenance is crucial.

Dwarf Mistletoe

  • common parasitic plantsDwarf mistletoe, referred to as Arceuthobium, is another noteworthy parasitic plant. Its vibrant orange-yellow hue distinguishes this parasitic intruder. Unlike oak mistletoe, dwarf mistletoe is more spiny and less circular, exhibiting a unique and intricate structure. This parasitic plant can induce structural changes in trees, with one common manifestation being the occurrence of branch brooms, also known as witch brooms.

These anomalies resemble abnormal clusters of twigs sprouting from a singular branch, altering the tree’s natural architecture. The harmful effects of dwarf mistletoe on trees are far-reaching. Extracting vital nutrients from the host weakens the tree and increases its vulnerability to other harmful parasites and diseases. Therefore, remaining vigilant and proactive in identifying and addressing dwarf mistletoe is essential for the health and longevity of trees in affected areas.

Signs of Parasitic Growth

  • The common signs of tree infection include the peculiar occurrence of branch brooms, unusual bole swelling, and the emergence of tree cankers. If you observe these signs in a tree, quick action is imperative. Contacting an arborist can mitigate the potential consequences.

Concerned about potential parasites affecting your trees and plants? Waste no time and reach out to American Tree Experts. Our team specializes in Proactive Disease Management for the well-being of your plants and trees. Call us today at (973) 744-6091 for a complimentary estimate of our services. We operate in Mont Clair, New Jersey, and nearby areas.

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