Archive for March, 2012

Palm Management in the Florida Landscape: May 8-9, 2012

Horticultural professionals can benefit greatly from “Palm School”.   This is a truly valuable educational opportunity.  I highly recommend it for all green industry professionals who manage palms in the landscape.  This class fills up quickly, so sign up early if you’re interested.

Date:  May 8-9, 2012 (2 days – Tuesday and Wednesday)

Time:  7:45 AM – 5:00 PM each day

Location:   University of Florida – IFAS Fort Lauderdale Research and Education Center

Reservations/Payment:  $300 by April 20, 2012 (or until class fills up)

CEUs requested:  ISA, FNGLA and FDACS (pesticide license)

CEUs for LA license approved (14.5):  Provider Number 0004406

Classroom and Field Topics: Ÿ Diagnosing Palm Problems, Palm Insects, Palm Anatomy and Growth,  Palm Diseases,  Physiological Disorders,  Normal Abnormalities, Nutrient Deficiencies,  Fertilizer Formulations, Sampling and Leaf Analysis,  Fertilizer Application Techniques,  Transplant Issues,  Pruning Palms

For more information and to reserve your spot for “Palm School”, download the brochure (Palm Management Training – May2012) or contact: Dr. Monica Elliott ; phone:  954/577-6315

Virtual Field Day for Property Managers! ~ Slide Show Attached

Palm Beach County / IFAS Extension conducts a biannual field day for property managers at a multifamily property.  The informal event consists of approximately 1 1/2 hours of plant, weed, insect, disease, and nutrient deficiency identification.  Best management practices are discussed and practical recommendations made.  This slide show, which can be downloaded below, was developed to provide a virtual field day experience, mirroring the live event held in November of 2011.

Virtual Field Day Fall 2011


Armillaria Root Rot

Armillaria Root Rot. Photo: Orli Zimmerman

INTRODUCTION ~ Armillaria root rot is a common disease of many trees in Florida.  Although it is better known as a forest disease, it can also be found in urban landscape trees.  It is often a secondary disease that takes hold after a tree is stressed or begins to decline.  It is common to see trees in groups with this disease because it spreads by rhizomorphs, which are shoestring-like fungal growths that can spread underground from tree to tree, as well as through wind-borne spores and direct root-to-root contact.

Mushrooms indicating Armillaria Root Rot (Older mushrooms). Photo: Orli Zimmerman

HOSTS ~  Armillaria root rot affects a wide host range.  Two of note in South Florida are the many ficus and oak species we commonly use in the landscape.

SYMPTOMS / IDENTIFICATION ~ Armillaria might not be particularly noticeable until the disease has significantly progressed.  A general decline, wilting, or dieback may be the noticed first.  This can be confused with or compounded by a number of other disorders.  The disease is better identified by the presence of the shoestring-like rhizomorphs and tan or honey- colored mushrooms near the base of the tree.  The rhizomorphs look like black shoestrings, and may even be confused with the root system of the tree.  Armillaria rhizomorphs are vegetative parts of the fungus; their function is to transport nutrients and increase the fungus’ size.  The rhizomorphs are easily confused with ficus trees’ many aerial roots.  Armillaria mushrooms may only persist for a few days.  White mycelium may also be present under the bark; mycelia are another vegetative portion of the fungus.  Their purpose is to absorb nutrients and decompose dead vegetative matter.

Armillaria Root Rot. Photo: Orli Zimmerman

LIFE CYCLE of the DISEASE ~ In an urban landscape, Armillaria root rot is often a secondary condition that affects a stressed tree.  Drought, disease, pest infestation, cold injury, over-pruning, and improper fertilization are some of the stresses that may initially affect trees.  Armillaria can be spread by airborne spores that come from mushrooms at the base of the trunk, or by the rhizomorphs.  Spores may enter a tree’s canopy through open wounds and rhizomorphs affect the tree by contact with its roots.  Spores may persist in dead tissues for well over ten years, should any part of an infected tree remain in the landscape.

LANDSCAPE MANAGEMENT ~  As with many landscape disorders, the most appropriate management technique is the avoidance of infection.  Maintain healthy trees by ensuring that proper pruning, fertilization, irrigation, and pest management techniques are used.  Commit to planting a more diverse landscape; diverse landscapes tend to better withstand pests, diseases, and even severe weather events.

Trees in the landscape affected by Armillaria should be removed in order to reduce the continued spread of this disease.  There are no fungicidal cures for Armillaria, however there is some evidence the fungicidal treatments may reduce the level of infection.  Fungicidal soil treatments can be used at planting to reduce the likelihood of infection in newly planting trees.  As always, disinfect pruning tools between plants to reduce the possibility of transmitting diseases.

Click here for a pdf version of this fact sheet: Armillaria Root Rot (2012) Sanagorski, L.

References and Further Reading

Cox, K.D., Scherm, H., Beckman, T.G. Armillaria root and crown rot.  Available at:

Florida forest diseases: Armillaria Root Rot.  Available at:

Williams, R.E, Shaw, C.G III, Wargo, P.M, & Sites, W.H. Armillaria Root Disease.  Available at:

Whitefly Fact Sheets

As you know, ficus, rugose spiraling, and other whiteflies have become an issue in South Florida.  Each has its own favorite plants to feed and reproduce on.  In addition to the damage younger stages of these whiteflies cause by feeding on plants, they produce a sticky substance called honeydew, which can support the growth of sooty mold, and ultimately, a big mess, and unsightly plant material.

Please see the following fact sheets, brought to you by UF / IFAS Palm Beach County Cooperative Extension Service and the Palm Beach County Whitefly Task Force.  These fact sheets are brief, and perfect for sharing with customers and homeowners.

  1. Whiteflies In Palm Beach County: Introduction (Whitefly Task Force Fact Sheet #1)
  2. Whiteflies In Palm Beach County: Life Cycle and Biology (Whitefly Task Force Fact Sheet #2)
  3. Whiteflies In Palm Beach County: Working with Natural Enemies (Whitefly Task Force Fact Sheet #3)
  4. Whiteflies In Palm Beach County: Selecting a Pest Control Company (Whitefly Task Force Fact Sheet #4)
  5. Whiteflies In Palm Beach County: Reducing Stress on Plants (Whitefly Task Force Fact Sheet #5)

Please watch the IFAS Palm Beach County Extension: Environmental Horticulture blog and our  Palm Beach County Whitefly Taskforce webpage for updates.

Congratulations to the UF / IFAS Palm Beach County 2012 Master Landscape Management class!

Congratulations to our 2012 Master Landscape Management participants!  On March 8, 2012, the 8-week program concluded.  38 professionals completed the program, with an additional 21 persons completing individual classes.  A total of 494.75 Continuing Education Units* were earned by this hard-working group!

2012 Master Landscape Management program

2012 Master Landscape Management program

Congratulations to all on a job well done!

This program was developed by Laura Sanagorski, Environmental Horticulture Extension Faculty, to encourage the use of University of Florida / IFAS research-based best management practices in the landscape, with a focus on the nine components of the Florida-Friendly Landscaping program.  If you missed the class this year, watch for program announcements this coming December for information about the 2013 program.

*  CEUs earned include: 8 Landscape Inspectors’ Association of Florida (LIAF), 60 Florida Nursery, Growers, and Landscape Association (FNGLA), 345 pesticide applicators, and 81.75 International Society of Arboriculture (ISA).

Limited Commercial Landscape Maintenance (LCLM) Course

UF/IFAS Palm Beach County Cooperative Extension Service will be offering four Limited Commercial Landscape Maintenance (LCLM) pesticide applicator courses this year.  An LCLM license allows the holder to apply “caution” labeled pesticides to shrub beds and sidewalks (no turf) and use up to a 3-gallon handheld sprayer or 5-gallon backpack for treatments.  The next LCLM workshop will be held:

April 12th, 2012, from 8:30am – 3:30pm, at 6500 Congress Avenue, Boca Raton (called the 6500 building)   

West Palm Beach classes to be held on August 8 and October 3

This course will:
  • Prepare participants to take the LCLM certification exam
  • Provide 6 required prerequisite CEUs
  • Explain related requirements and laws
  • Assist applicants in understanding the licensing process

In Palm Beach County, your GI-BMP team is:

  • Frank Dowdle, Agricultural Safety Extension Agent email
  • Laura Sanagorski, Environmental Horticulture Extension Agent email
  • Bill Schall, Commercial Horticulture Extension Agent email
To attend this class, you can download the 2012 LCLM Brochure or call 561.233.1725.