Understanding and Controlling the Leaffooted Plant Bug

Q. What is the best attack for these pesty, scary looking creatures.  We had them last year.  Haven't seen them yet this season.  Is there something to keep them away? 

A. This first part I am explaining will be a bit late for you now but prevention should start during the winter months when they can be seen in the landscape as overwintering adults ready to lay eggs in the spring. I have seen adults on bottlebrush in home landscapes in southern Nevada and I am sure they are probably overwintering on a number of evergreen plants in winter months. 

Leaffooted plant bug on nopal cacttus.

Leaffooted plant bug on pomegranate.

From: http://www.whatsthatbug.com/2009/02/25/mating-leaf-footed-bugs-3/

Eggs of leaf-footed bug. Photograph by Lacy Hyche, Auburn University.

Nymph of the western leaffooted bug. Photograph by Henry Fadamiro, Auburn University.

Since these insects can fly as adults they will move from plant to plant for sources of food. This means that they will come into your yard from neighbors as well all during the growing season. So just because you control them once during the season you will have them again as long as there is food in your yard for them to eat.

What do we know about leaffooted plant bug?

• They like to feed on pomegranates, almonds, pistachios, tomatoes, peppers, cucumbers, squash, corn, peach, nectarine and I am sure some others.
• They are closely related to stinkbugs and squash bugs, feed and reproduce like them and can be confused with them because they look kind of similar.
• They overwinter from year to year in the landscapes.
• It takes about 50 or 60 days to produce adults from eggs laid in the spring.
• They feed with a long hypodermic needle-like mouth that is inserted into soft plant tissue like leaves and fruit.
• Their feeding early when fruit is developing can cause threads of sap to stick out of the fruit.
• Their feeding causes misshapen fruit or causes fruits or nuts to drop off of the tree.
• Their feeding can also cause diseases to enter the fruit.

How to Control Them

They are difficult to control because they hide unless they are swarming and reproducing near the fruit.

Hard or conventional pesticides such as Sevin or synthetic pyrethrins are the most effective for rapid kill. These can be found as ingredients in some common vegetable or fruit sprays in nurseries or garden centers. 

These same ingredients are used commercially where leaffooted plant bug is active. These types of chemicals leave behind a residual on plants that offer some protection for a number of days after they are applied. They also present some safety concerns for homeowners when used without caution in home landscapes so make sure you read the label thoroughly if you choose to go this route.

Organic control is more difficult because these chemicals are short-lived and don’t leave behind much of a residual. You will not control this pest without more work on your part when using organic methods. That is the tradeoff when using organic methods. With conventional pesticides like Sevin a few passes during fruit set and development will give you some good control. Organic methods may require more inspection of the tree and fruit on your part and spraying more frequently. 

Soap sprays like Safers insecticidal soap will give good control if the spray lands on the insects. It leaves no residual once sprayed. Oils like Neem have been reported to give good control. Other oils include horticultural oils and canola oil. Organic sprays like Bt will not work on this insect. Spinosad has not been reported to work on this insect either. Another possibility are pyrethrin sprays which may give you good knockdown when sprayed on them directly.

A common mistake is to think that just because they organic sprays they will not hurt anything except the enemy insect. This is not true. Organic sprays will kill many different insects, good and bad. So directing the sprays at the enemy insects is important. It is also important to spray very early in the morning or near sundown. Spray when there is no wind and cover both the upper and lower sides of the leaves. Do not use one spray over and over. Use several sprays in rotation with each other so you do not end up with an explosion in the population of insects not controlled or building up insect immunity to the spray.