Integrated Management of Palm Pests Tom Weissling Assistant Professor of Entomology University of Florida Fort Lauderdale Research & Education Center

Effective design and implementation involves knowledge and planning What is Integrated Pest Management? "Integrated Pest Management (IPM) is a sustainable approach to managing pests by combining biological, cultural, physical and chemical tools in a way that minimizes economic, health and environmental risks." From: Anonymous. 1994 Integrated Pest Management Practices in 1991 Fruits and Nuts, RTD Updates: Pest Management, USDA-ERS, 8pp. Effective design and implementation involves knowledge and planning

Biology and Identification of Pests and Beneficials Preventative Practices Evaluation & Follow-up IPM Program Make Action Decision Monitor Pest Populations Action Threshold

Preventing Pest Problems/Outbreaks When Installing Palms 1. When buying, select only palms that are healthy and free of pests Many pest problems in managed areas are attributed to importation via infested plant material

Preventing Pest Problems/Outbreaks When Installing Palms 2. Avoid species that typically have pest problems Especially palms susceptible to Lethal Yellowing Consider nutritional requirements

Preventing Pest Problems/Outbreaks When Installing Palms 3. Select native palms or palms well adapted to our climate

Preventing Pest Problems/Outbreaks When Installing Palms 4. Site selection Species planted in “off-site” locations may experience stress leading to attack by pest organisms In addition, stressed trees may be slow to recover from pest damage

Preventing Pest Problems/Outbreaks When Installing Palms 5. Site Preparation/Planting Choose a well-drained location Do not plant too deep Support after installation NAILS

Preventing Pest Problems/Outbreaks In Established Palms 1. Proper cultural care a. Establish a fertilization program 4 times per year with a 100% slow release product 2N-1P-3K-1Mg plus micro- nutrients at 1.5 lbs per 100 ft2

Preventing Pest Problems/Outbreaks In Established Palms 1. Proper cultural care b. Pruning In the Canary Island date palm, pruning can create wounds that attract palmetto and silky cane weevils

Preventing Pest Problems/Outbreaks In Established Palms 2) Habitat modification plant several plant species of differing canopy heights in an area This can help to enhance populations of predators and parasitoids

Pay close attention to the symptoms observed: Don’t be too quick to blame the bugs! May be a nutritional problem or a disease

Decision Making (Action Thresholds) Most pests often perceived as “Zero Tolerance” Categories to consider: 1. Pest is lethal to the palm 2. Pest is serious but manageable 3. Pest causes only aesthetic damage

“Lethal” palm pests

The Palmetto Weevil, Rhynchophorus cruentatus Native to Florida Host range: - Cabbage palmetto (Sabal palmetto) - Saw palmetto (Serrenoa repens) - Coconut palm (Cocos nucifera) - Canary Island date palm (Phoenix canariensis) - P. dactylifera - Pritchardia spp. - Washingtonia spp. - Roystonea spp. - Latania spp. - Caryota spp.

Installed Sabal Palm exhibiting “pop necking”

Palmetto Weevil Grubs in Crown

Palmetto Weevil Adults

In the past, palmetto weevils attacked only sabals and saw palmetto that were dying from some other problem. They were considered a secondary pest They are now considered, along with the silky cane weevil, to be primary pests of Canary Island date palms Unfortunately, infestations in apparently healthy date palms is lethal

Decline of Canary Island date palms infested with the palmetto weevil Total loss of more than 500 date palms within a year Some showed signs of previous cane weevil infestation Palms were about 10 years old

Decline can be rapid (a few months) Be careful not to confuse with lethal yellowing Tear palm apart and look for grubs, pupae, adults, feeding damage

Treatment ineffective: Infested palms should be removed and destroyed as soon as possible Future: Mass trapping Prophylactic insecticide applications

Some “serious” palm pests

Banana Moth: Serious but can be treated with some insecticides and nematodes

Royal Palm Bug: Serious but can be treated with systemic insecticide (imidacloprid)

Silky Cane Weevil: Serious but can be treated with some insecticides and nematodes if caught early

Aesthetic Problems: Usually not causing injury to plant or stressing it Problem is usually short-lived and disappears on its own or natural enemies take care of problem Comes down to how much you can stand

www.ftld.ufl.edu A downloadable slide show located at the University of Florida’s, Fort Lauderdale Research and Education Center Web Site: www.ftld.ufl.edu Follow entomology or horticulture links

Authors: Tom Weissling, Alan M. Meerow, University of Florida Photos: University of Florida Unless otherwise credited Entomology And Nematology Department & Environmental Horticulture Department, Copyright University of Florida 2000 For more detailed information see the Featured Creatures WWW site at http://creatures.ifas.ufl.edu/