The Four Lined Plant Bug is a Real Thug!

Ben HenryMay 17, '20
The Four Lined Plant Bug is a Real Thug!

The four–lined plant bug, Poecilocapus lineatus which is easily identified by the four black strips running down its back, has a wide range of hosts including: fruits, vegetables, flowers, herbs, and cucurbits. Many of our customers have brought in plants that a covered with a series of ugly, purple spots. The associated damage consists of spots that look similar to fungal disease spot and can be misidentified as such. Damage is inflicted by the bug's piercing–sucking mouthparts and is usually not severe enough to cause plant death but can disfigure it for the growing season. These “Little Thugs’ are extremely agile and move quickly; you may never see the critter that is causing all the problems.

The four–lined plant bug nymphs are a bright red to orange color with black dots on the abdomen. Later hacthes have black wing pads running ½ way down the abdomen with a yellow strip on each wing pad; they do not have actual wings however. Adults are usually a greenish–yellow color with four black strips running longitudinally down the wings. The head, antenna, and body are all black in color while the legs are yellow–green with black marks. Both nymphs and adults have piercing–sucking mouthparts. During the fall, the banana shaped eggs are laid at right angles in vertical slits measuring 2 to 3 in. along the plant’s stem. They are usually not laid individually but instead are laid in groups of six or more. The eggs will over winter and hatch in May or late June just after the plant's foliage emerge. Nymphs will remain near their hatching site and feed on the upper side of leaves removing the plant's chlorophyll. After advancing through five molts in a period of about six weeks, the four–lined plant bug will have matured to an adult form. Adults will feed, moving from plant to plant, for approximately one month before mating; adults will not overwinter, and there is only one generation per year. With piercing–sucking mouthparts, the four–lined plant bug removes the plant's chlorophyll leaving a window of upper and lower epidermis. A toxin present in their saliva is also secreted during feeding that digests the components responsible for holding the plant cells together. This feeding produces white, dark, or translucent spots 1/16 to 1/8 in. in diameter on the plant's leaves, which can merge together (if there is substantial damage) forming large blotches. Entire leaves can turn brown, curl up and eventually fall off. If feeding occurs on new growth, wilting may result. It’s important to control these “Bug Thugs”.

Information about the life cycle of the Four Lined Plant Bug from:
A. Genetzky, E. C. Burkness and W. D. Hutchison — 
Department of Entomology, University of Minnesota

Organic Treatments

Dr. Earth Pro–Active™ Home & Garden Insect Spray

Formulated with essential oils and garlic extract to knock down and kill insects quickly, the results are apparent from immediately to several minutes. Dr. Earth Pro–Active™ works to block Octopamine neuroreceptors. Octopamine is a chemical neurotransmitter that controls body movement and metabolism in insects and mites. The ingredients in Dr.Earth Pro–Active™ interefere with the transmission of Octopamine signals throughout an insect’s body. The intereference of these signals leads to metabolic toxicity, immobilization and ultimately death. Garlic extract has been proven to repel insects for several weeks or longer.

Bon–Neem Insecticidal Soap By Bonide

Potassium Salt of fatty acids derived from Neem seed oil 25%
Derived from the botanical oils of Neem tree seeds. Treat ornamental trees, shrubs, flowers, bedding plants & vegetables.

Japanese Beetle Killer RTU by Bonide

Pyrethins – 0.02%
Piperonyl Butoxide – 0.20%
Natural pyrethrum for quick and easy kill of Japanese Beetles on vegetables, flowers, ornamentals, trees and shrubs.

Conventional Controls

Eight Insect Control by Bonide

Permethrin – 2.5%
Use on vegetables, fruits, flowers, roses, ornamentals, lawns, trees and shrubs. Keeps working for up to 4 weeks.

Triazicide Insect Killer Once & Done™ by Spectracide

Gamma–Cyhalothrin – 0.25%
Use on vegetables, fruits, flowers, roses, ornamentals, lawns, trees and shrubs. Fast acting formula, kills on contact! Keeps working for up to 8 weeks.

Systemic Insect Control by Bonide

Acephate – 9.4%
Use on roses, flowers, ornamentals, shrubs and trees.

Beetle Killer by Bonide

Lamda–cyhalothrin – 0.5%
Lamda–cyhalothrin concentrate provides the punch in this new product to knock out even the toughest beetles, like Colorado Potato, Japanese, Mexican Bean, Asian Lady, Asian Longhorn and others. Low odor, non staining formula quickly kills and repels for up to 8 weeks. Great for vegetable and flower gardens (treats up to 16000 sq. ft.), as well as trees, shrubs, turf & ornamentals. Comes with our “Twist and Shoot” adjustable sprayer to reach trees up to 25' tall.

Carefully read the directions on all the products listed above. Follow precautions and mixing instructions.


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