According to David Pichon, county agent for St. John the Baptist Parish, many homeowners with citrus need to be on the lookout for the leaf-footed plant bug. This bug attacks citrus, generally satsumas but also other citrus fruits, by piercing the fruit with its mouth and causing the fruit to fall from the tree.

The leaf-footed plant bug is attracted to the citrus fruits as they begin turning yellow to ripen. If the homeowner sees his fruit suddenly dropping off the tree in large numbers, then he needs to look for the insect. According to Pichon, an easy method to check for the plant bug is to shake the limbs on the tree and look for the bugs flying away. The plant bug, which some people refer to as a giant stinkbug, is sometimes mistaken by some homeowners to be a wasp flying from the tree. Also, as the plant bug flies by you, you may hear a humming or clicking noise coming from the insect’s wings.

The leaf-footed plant bug can be controlled by spraying the tree with Malathion or Baythroid. Pichon recommends always following the labeling on the insecticide container as per mixing instructions and also being aware of possible withdrawal times. The withdrawal time is the number of days you must wait after spraying an insecticide until you can harvest the fruit from the plant.

Other citrus damage being reported by homeowners is generally caused by spider mites, leaf miners, aphids, whiteflies, blackflies and other insects that suck sap from the leaf causing the leaf to turn yellow and possibly fall from the tree. Homeowners can generally call the AgCenter Office when they see a black mold forming on the leaf. According to Pichon, the black mold is growing on honeydew, a sugary substance excreted by the sap-sucking insects.

These insects can generally be controlled by sprays of Malathion, Spinosad, Kelthane and Summer Oil. A new product, CoreTect tablets, may be applied to the ground at the base of the tree and can control most insects for about one year. Merit 2F is another long-term insecticide in liquid form that may be applied to the roots of citrus trees and also protects the tree systemically.

For more information on controlling insects in citrus, call your local LSU AgCenter county agent. David Pichon may be contacted by phone at 985-497-3261 or by email at dpichon@agctr.lsu.edu. You may also go to the LSU AgCenter website at lsuagcenter.com and type in “citrus” in the search box and purchase for $5 the Citrus Bulletin – Publication No. 1234 – Louisiana Home Citrus Production. This bulletin may also be purchased at the AgCenter’s Office’s located in each parish.

If you have any questions, please contact your local LSU Ag Center County Agent. You can contact David Pichon, County Agent-St. John Parish at 985-497-3261 or by email at dpichon@agctr.lsu.edu.