Considerations in Palm Pest Management Tom Weissling Assistant Professor of Entomology University of Florida Fort Lauderdale Research & Education Center

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 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 PreventativePractices Monitor Pest Populations Action Threshold Make Action Decision Evaluation & Follow-up IPMProgram

IPM requires proper identification of the pest(s) and knowledge of the pest(s) biology Is it a pest or beneficial? Is it a pest or beneficial? Is it damaging the plant? Is it damaging the plant? What type of damage is it doing? What type of damage is it doing? Is it injuring the plant or is it Is it injuring the plant or is it just causing aesthetic problems? just causing aesthetic problems? Is it persistent? Is it persistent? When is it most damaging? When is it most damaging?

Pest Complex (sap suckers) Palm Aphid Damage: usually aesthetic

Pest Complex (sap suckers) Mealybugs Damage: usually aesthetic in the landscape in the landscape

Pest Complex (sap suckers) Scale Insects Damage: usually aesthetic but can get bad but can get bad

Pest Complex (sap suckers) Whiteflies Damage: rare in the landscape landscape

Pest Complex (sap suckers) Royal Palm Bug Damage: can be severe

Lethal Yellowing vectored by the American palm cixiid, Myndus crudus Pest Complex (Disease Vectors)

Pest Complex (Foliage chewers) Caterpillars Damage: usually aesthetic

Palm Leaf Skeletonizer Pest Complex (Foliage chewers) Damage: usually aesthetic

Pest Complex (Raspers) Spider Mites Damage: usually aesthetic

Pest Complex (Raspers) Thrips Damage: usually aesthetic

Pest Complex (Borers) Ambrosia Beetles Damage: usually secondary to other problems to other problems

Pest Complex (Borers) Banana Moth Damage: usually lethal

Silky Cane Weevil Pest Complex (Borers) Damage: severe - lethal

Palmetto Weevil Pest Complex (Borers) Damage: Lethal

Keep Track of Pests and Beneficials by Monitoring Populations Visually inspect plants to be protected Visually inspect plants to be protected Looking for: Looking for: Conditions that might lead to pest problems Conditions that might lead to pest problems Health of the plant Health of the plant Signs of the pest (damage, excrement, etc.) Signs of the pest (damage, excrement, etc.) The actual pest (count number/leaf, stem) The actual pest (count number/leaf, stem) Beneficial organisms Beneficial organisms

 Standard 10X hand or pocket lens  Pocket knife  Tweezers  Collection vials  Paper bags  Field identification guide  Notebook or data sheet Monitoring Tools

Surveying Methods: BEAT TRAYS Semiochemcial Traps +

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

Preventing Pest Problems/Outbreaks 1. Install plants that are likely to thrive Plant only pest free palms Plant only pest free palms Choose plants well adapted for our climate Choose plants well adapted for our climate Avoid plants that have severe pest problems Avoid plants that have severe pest problems

The Palmetto Weevil, Rhynchophorus cruentatus Host range: 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. Native to Florida Native to Florida

Installed Sabal Palm exhibiting “pop necking”

Palmetto Weevil Grubs in Crown

Palmetto Weevil Adults

In the past, palmetto weevils attacked only In the past, palmetto weevils attacked only sabals and saw palmetto that were dying from sabals and saw palmetto that were dying from some other problem. some other problem. They were considered a secondary pest They were considered a secondary pest They are now considered, along with the They are now considered, along with the silky cane weevil, to be primary pests of silky cane weevil, to be primary pests of Canary Island date palms Canary Island date palms Unfortunately, infestations in apparently Unfortunately, infestations in apparently healthy date palms is lethal 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 Total loss of more than 500 date palms within a year a year Some showed signs of previous cane weevil Some showed signs of previous cane weevil infestation infestation Palms were about 10 years old Palms were about 10 years old

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

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

Cycad Aulacaspis Scale

Consider installing different cycad species until pest is more easily managed

2. Avoid stress on palms Install in proper location for species Install in proper location for species Take care during transplanting Take care during transplanting Follow proper horticultural care procedures Follow proper horticultural care procedures Fertilization Fertilization Irrigation Irrigation Pruning Pruning Sanitation Sanitation

3) Habitat modification. Make habitat less desirable to primary pest species desirable to primary pest species (i.e., try to plant several versus a single (i.e., try to plant several versus a single plant species in an area) plant species in an area) This can help to enhance populations of predators and parasitoids

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

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

Cultural Methods Cultural Methods Mechanical Methods Mechanical Methods Physical Methods Physical Methods Biological Control Biological Control Chemical Control Chemical Control If you choose to manage pest problems, there are many tactics to choose from:

Evaluation and Follow-up Important to evaluate how well control Important to evaluate how well control measures worked measures worked Can be determined during weekly monitoring Can be determined during weekly monitoring

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

Author: Tom Weissling, Alan W. Meerow, University of Florida Photos: University of Florida, Jim Defilippis Entomology And Nematology Department Copyright University of Florida 2000 For more detailed information see the Featured Creatures WWW site at