Tree Pest and Disease Treatments: What to expect.

The process of treating for a tree disease or pest is a complicated one.


One of the more difficult portions of my job is to provide easily understandable level of expectations to my clients. Treatment protocols are sometimes complicated. Some treatments are more effective than others. Some treatments are almost immediate. Clients can see visible results in the tree within a few days or weeks. Others, can take up to 3-5 years or more before there will be a noticeable difference in the health of the tree. And to that last point, all of the results will depend on a  wide variety of factors (largely outside my or anyones control). Most of the disease and pest treatments are in that latter group. Where visible results usually take at least a year or more.

There are several challenges when deciding to do a certain treatment on to to a tree:

  • Waiting:

    • Waiting the year or more to see a change can be very difficult. Especially if the costs of treatment are a hefty investment.
  • Knowledge of the Tree:

    • How well you know how your tree should look and behave can be challenging to knowing if there is a change or not.
  • Control vs Management:

    • Some pests or diseases can only be managed (can’t be eliminated). Others are controlled (eliminated). Understanding the difference beforehand can help with knowing what to expect.
  • Deciduous vs Evergreen:

    • Generally, issues with deciduous trees are on a year by year basis. Since the leaves fall off every fall and grow new the next year. So fungal leaf issues are year to year. But with evergreens, they can hold up to 7 years of needles. That means it ill take a needle 7 yeasrs before it would naturally fall off. If those needles become damaged or infected with a disease, they may persist for that time period.


Questions to ask your arborist.

There are many more considerations and challenges when it comes to treating tree, and a lot of it will depend on the species of tree you have and the particular problem you have with that tree. But here are some questions to ask and things to consider when venturing into a tree treatment plan:

  • How long until I can expect to see results?

  • Is the treatment a one time application or multiple applications

  • How long will my tree be protected or cured?

  • How much will it cost?