Phytophthora (Pronounced ‘Fi-TOFF-thor-uh’)

Time for a quick self-guided inspection of your trees. IF you have an Oak, Maple, Birch, or Beech, go out and look at the lower trunk of the tree, up to about 4 feet off the ground. IF you find darkened black/ brown weeping spots approximately the size of a quarter or smaller on the bark and lower trunk, I recommend reaching out to your Wachtel Tree Science arborist. This disease can affect many more tree species but is most visible on the four listed above.
You might now be asking yourself, what Phytophthora is and why must I go outside now and trudge through snow to look at my trees? Phytophthora is a fungus-like organism better known as a “water mold”. It travels through soil during wet/ saturated soil conditions and infects roots. This infection impairs the root and vascular system’s ability to uptake and move water and nutrients throughout a tree. The pathogen can also be splashed directly onto a tree’s trunk during rainfall or during irrigation if there is bare soil exposed around the trunk of a tree. The bleeding cankers (which you just went outside to try and observe, right?) leak tree sap much like an open sore would on a human or animal. Left unchecked, Phytophthora will weaken a tree’s overall health and vigor over time. The advancement of this disease often leads to canopy dieback and premature tree death.
All is not lost though! If caught early, this disease can be suppressed enough with treatments to allow a tree to outgrow an infection. Earlier, I asked you to take a quick look at your trees. The reason for this is because an infection can visibly form within a few short years and winter is a great time to inspect and try to identify this disease. Herbaceous plants like Hostas, which are often planted around the lower trunk of a tree, can hide these cankers during the growing season unless you happen to be digging around in the garden looking for this disease. Contact our office or your Wachtel Tree Science arborist directly if you find spots that may look like Phytophthora on your tree(s). Accurate diagnosis is important to be sure that other issues are not causing the bleeding sap from a tree. Our arborists are out inspecting trees during winter and available to continue helping you care for your trees as well!

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