The presentations from the cancelled 2020 Florida Citrus Growers’ Institute, including one on trunk injections, are being made available online.

The 2020 Florida Citrus Growers’ Institute was cancelled due to Covid-19, but UF/IFAS is making as many of the presentations available online for Florida citrus growers as possible. Ute Albrecht, a UF/IFAS plant physiologist with the Southwest Florida Research and Education Center in Immokalee was slated to give a presentation on trunk injections, according to a Citrus Industry article. See the details of the presentation below.

Details on Trunk Injections

The presentation, titled “Trunk Injection: Difficulties and Considerations,” looked at utilizing trunk injections into the xylem of citrus trees to deliver an array of treatments to the tree. Albrecht pointed out that this is as opposed to the phloem, where the citrus greening-causing bacteria reside. “Trunk injection is a targeted application of pesticides, plant resistance activators, fertilizers or other materials in the stem or trunk … as an alternative to spraying or soil drenching,” Albrecht explained.

Holes are drilled into the tree trunk, or needles are used, to inject whatever is necessary into the tree. Injections into a tree’s trunk can be used to address insects, nematodes, fungi, bacteria, and phytoplasmas.

Advantages of using a trunk injection, as cited by Albrecht in the article, include:

  • Precise delivery of materials.
  • Elimination of spray drift.
  • Reduced risk of worker exposure.
  • Reduced risk for non-target organisms.
  • Reduced pesticide load into the environment.
  • Lengthening of time that materials are biologically active.

Disadvantages of utilizing trunk injections include:

  • Time.
  • Labor.
  • Cost of injection.
  • Wounding of trees.
  • The impact on long-term tree vitality.
  • Phytotoxicity may occur.
  • One-time injections won’t prevent recurrent insect colonization and pathogen infection.

The presentation in video form can be viewed here, with an accompanying PDF presentation available here. As an added bonus, continuing education units (CEUs) for those with Restricted use pesticide licenses and Certified Crop Advisors can be gained by viewing the presentations, here.