Pest Management Update Anita Neal UF/IFAS SLC Extension
A New Exotic Soft Scale Insect on Croton in South Florida (Hemiptera: Coccoidea:Coccidae) • This is an undescribed species in an undescribed genus of unknown origin. Currently, efforts are being made to describe this new scale insect. Adult and immatures of this new scale insect on croton
Croton Scale FLORIDA DISTRIBUTION: Broward, Duval, Indian River, Lee, Miami-Dade, Monroe, Orange, Palm Beach, Pinellas, Putnam, and St. Lucie counties. Male Adult female, adult male and immatures of this new scale insect on croton
Homeowner Controls • Bayer Advanced Garden Power Force Multi-Insect Killer – Cyfluthrin • Bayer Advanced Garden 2-in-1 Systemic Azalea, Camellia & Rhododendon Care – Dysulfoton • Bayer Advanced Garden Tree & Shrub Insect Control – Imidacloprid • M-pede & Safer’s Soap – Potassium Salts • Spectracide Rose & Flower Insect Spray - Pyrethroid
Redbay Ambrosia Beetle, Xyleborus glabratus Eichhoff (Scolytinae:Curculionidae) • The redbay ambrosia beetle, Xyleborus glabratus Eichhoff, was first detected in Georgia 2002 and in Florida in 2005. • This ambrosia beetle introduces an unspecified vascular fungus (Ophiostoma sp.) into its host causing infected redbays to wilt and die within a few weeks or months. Lateral view String of compacted ambrosia beetle sawdust on redbay Dorsal view
Redbay Ambrosia Beetle • As the female redbay ambrosia beetle bores tunnels into the wood, she lays her eggs in galleries. These eggs hatch and the larvae feed on the fungus, pupate and change into adults. • Only one female beetle is needed to establish a new population. Unmated females lay eggs that hatch as males, while mated females lay eggs that hatch as females. Multiple generations are produced per year. • Only the female beetles are able to fly and initiate attacks on a new host of trees • Do Not transport Firewood from Infested areas
Redbay Ambrosia BeetleLaurel Wilt Fungus • Potential problem for avocados • Most ambrosia beetles attack trees and shrubs that are stressed, dying, or dead. Plant stress may be the result of drought, flooding, freezing temperature damage, wind damage, or very poor cultural practices. In contrast, some ambrosia beetles, the redbay ambrosia beetle included, attack healthy trees. More importantly, the laurel wilt fungus that accompanies this beetle often causes tree death. A bore-hole from a redbay ambrosia beetle surrounded by dried sap (white-crystal-like) from an avocado stem and wilted leaves of laurel-wilt-infected avocado tree
Laurel Wilt • Laurel wilt causes the leaves of affected trees to droop and take on a reddish or purplish discoloration. Wilted foliage may occur in only part of the crown at first, but typically the entire crown eventually wilts and reddens. • In redbay, the leaves eventually turn brown and remain on the tree for up to a year or more. • Limited experience with laurel wilt in avocado suggests that this host may drop its leaves relatively soon after wilting. • Removal of bark from wilted trees reveals a black to brown discoloration in the sapwood. This is the best diagnostic feature of laurel wilt in the field. The extent of this discoloration, which runs in streaks parallel to the grain of the wood, will vary depending on how long the tree has been infected
What You Can Do • Avoid long distance transport of firewood in general. A county-level distribution map is periodically updated on the following website: http://www.fs.fed.us/r8/foresthealth/laurelwilt/dist_map.shtml • Whenever possible, leave dead and dying redbay wood (and wood from other laurel family hosts) on site instead of transporting it. If the wood must be transported, dispose of it as close to the source as possible • Urban and rural residents and commercial growers should be on the look-out for redbay and other host trees (including avocado) showing signs of rapid wilting and dark sapwood discoloration. Report new finds to the Florida Division of Plant Industry (http://www.doacs.state.fl.us/pi/) or Division of Forestry • Treat at the root flare with propiconazole (Alamo) & Thiabendazole (Arbotect) as macroinfusion (innoculated) http://www.fs.fed.us/r8/foresthealth/laurelwilt/index.shtml
Emerald Ash Borer • Emerald Ash borer is an exotic beetle that was discovered in southeastern Michigan near Detroit in the summer of 2002. The adult beetles nibble on ash foliage but cause little damage. The larvae (the immature stage) feed on the inner bark of ash trees, disrupting the tree's ability to transport water and nutrients. • It only attacks Ash trees, Fraxinus sp.
Emerald Ash Borer • The adult beetles are metallic green and about 1/2-inch long. • Adults leave a D-shaped exit hole in the back when they emerge in spring. • Woodpeckers like EAB larvae; heavy woodpecker damage on ash trees may be a sign of infestation. • Firewood cannot be moved in many areas of Michigan, Ohio, Illinois, Indiana, Pennsylvania, West Virginia and Maryland because of the EAB quarantine • It probably came from Asia in wood packing material • More information: http://www.emeraldashborer.info/
Potato Cyst Nematodes • Potato Cyst Nematode (PCN) is a serious pest of potatoes world-wide and is subject to stringent quarantine and/or regulatory procedures wherever it occurs. PCN can be a devastating pest of potatoes in temperate regions if not controlled. • It is in 65 countries, intro into US from WWI equipment returning from the war (NY). • Spread by tubers and soil residue • Potential into Florida through potato seeds (Minn., Maine and South Dakota) • Above ground symptoms • Chlorosis • Stunting of growth • Incipient wilting
Sabal Palm Decline • Texas Phoenix Palm Decline (TPPD) • Disease is caused by a phytoplasm • Noticed winter/spring 2008 – Manatee Co. • The earliest symptom is a discoloration of the lower (oldest) leaves of the palms. • Discoloration begins at the tips of the leaflets. • Then reproductive parts of the plant will die, resulting in dropping of fruits and flowers • In Phoenix palms the spear leaf dies, in Sabals it may not.
Sabal Palm Decline • Red coloration on dead leaves • The bud will be loose • The insect vector, probably a planthopper or leafhopper is unknown. It could be the same leafhopper that vectors lethal yellow. • Homeowners who suspect TPPD should contact their local UF/IFAS County Extension Office. • The sampling process is at http://flrec.ifas.ufl.edu/pdfs/LY-TPPD-Trunk-Sampling.pdf • Samples can be sent to the Fort Lauderdale Research and Education Center
The Unlucky Side of Lucky Bamboo • Aka ‘Belgian evergreen’; Host name : Dracaena sanderiana • Extremely popular in Asian theme interior decorating • Plant is very hardy for interiorscaping applications • Large volume imported from China over last several years • Pathogen probably introduced in this time frame
Unlucky Bamboo • Fungal pathogen – Colletotrichum dracaenophilum • Water-splashed conidial inoculum • Geographic range – China, Bulgaria-2007 (PD 92:173), Dominican Republic and Florida-2008 • Symptoms are relatively mild at first and apparently can remain static for some time. Look for slightly raised brown patches on the stem, surrounded by a maroon-colored border
Consequences - Significance • Another example of the international phytosanitary system being overwhelmed by volume • Commodity is treated much like a product for consumption; a potted plant, not outplanted into environment much • What is host range of C. dracaenophilum? • Probably much too late for any meaningful regulatory response • Maintain vigilance to avoid any more introductions, stop further spread
Recent Thrips Records of Interest Submitted to the Division of Plant Industry • Common name, the weeping fig thrips. • Primary host, Ficus benjamina. • Heavy infestations frequently reported. Rolls leaf edges into ‘galls’ followed by leaf drop. • Predators: Androthrips ramachandrai (Phlaeothripidae), Montandoniola moraguesi (Anthocoridae).
Holopothrips tabebuiaCabrera & Segarra • Recently described, formerly referred to as Holopothrips cf. inquilinus (Bournier). • Primary host, Tabebuia spp. • Also makes leaf roll galls similar to Gynaikothrips spp. • Has same predators as Gynaikothrips spp.
Tabebuia Damage Notice the severe leaflet curling and galling caused by Holopothripstabebuia
Holopothrips tabebuia These make protective galls in which they lay eggs where the larvae live and feed.
Liothrips spp. Liothrips varicornis Hood Hibiscus thrips Liothrips floridensis (Watson) Found on camphor Large thrips with bright red larvae. Echinothrips americanusMorgan • Seems more abundant than usual this year. • On a number of ornamentals including Dieffenbachia, Poinsettia, Spathoglottis, and Syngonium.
Selenothrips rubrocinctus(Giard) Always one of the most frequently submitted thrips. Red-Banded Thrip Has wide host range, including native plants.
Scirtothrips dorsalis Hood Most frequently submitted thrips overall. Distribution (27 counties) and host range continue to expand. Significant new agricultural hosts: Strawberries (Jim Price) Blueberries (Lance Osborne) Frankliniella spp. • F. bispinosa (Morgan) continues to be the most frequently submitted flower thrips from a wide variety of hosts. • F. occidentalis (Pergande) is submitted about as frequently as F. bispinosa, also from a wide variety of hosts.