The Leaf-footed Bug, Is this bug bugging you?





Have you seen a large, brown bug walking around your walls and windowsills this fall?  It probably is a leaf-footed bug.  This nuisance insect invades homes in late summer and early fall looking for a warm crevice to spend the winter.  They can fly but are most often seen walking on windows and walls.  They do not injure houseplants or bite humans, though their large size and slow flight around the house can be startling.


There are several leaf-footed bugs that live in Connecticut.  They are members of the order, Hemiptera, and in the true bug family, Coreidae.  Leaf-footed bugs get their name from the flattened, leaf like flare on the lower portion of the back legs or tibia.  They are brown with white marks on the margins of their folded wings.  They closely resemble an insect that vegetable gardeners are familiar with, the squash bug.  The most important economically is the Western conifer seed bug (Leptoglossus occidentalis).  A relatively new pest, it was first identified in Connecticut in 1985.  They are relatively large bugs, getting to be one inch in length.  Other leaf-footed bugs can be grayish to black.


Leaf-footed bugs feed on the flower, cones and seeds of many species.  They are known to do damage to nut trees such as almond and pistachio.  The conifer seed bug does most of its damage in conifer seedling operations.  They have a long sucking mouthpart that pierces the flowers or fruit.  This damage causes misshapen, unmarketable nuts.


Adults emerge in spring and feed on flowers and newly forming seeds.  Soon they mate and lay eggs on host trees.  The eggs hatch after about 10 days and the nymphs start feeding.  There are five nymph stages, called instars before adulthood.  It’s this nymph feeding that causes the most economic damage.  They are adults by August and continue to feed through the fall.  They overwinter as adults in protected areas including your house.  There is only one generation per year.


Control of leaf-footed bugs is not necessary (unless you’re a pinecone grower!)  They are easy to catch because of their slowing metabolism.  Once caught, they can be tossed outdoors to find somewhere else to stay for the winter.  Be advised, these are members of the stink bug family.  If held too long or crushed, they emit a foul odor.


Written by: Robert Durgy, Dept. of Plant Science, University of Connecticut


The information in this material is for educational purposes. The recommendations contained are based on the best available knowledge at the time of printing. Any reference to commercial products, trade or brand names is for information only, and no endorsement or approval is intended. The Cooperative Extension system does not guarantee or warrant the standard of any product referenced or imply approval of the product to the exclusion of others which also may be available. All agrochemicals/pesticides listed are registered for suggested uses in accordance with federal and Connecticut state laws and regulations as of the date of printing. If the information does not agree with current labeling, follow the label instructions. The label is the law. Warning! Agrochemicals/pesticides are dangerous. Read and follow all instructions and safety precautions on labels. Carefully handle and store agrochemicals/pesticides in originally labeled containers immediately in a safe manner and place. Contact the Connecticut Department of Environmental Protection for current regulations. The user of this information assumes all risks for personal injury or property damage. Issued in furtherance of Cooperative Extension work, Acts of May 8 and June 30, 1914, in cooperation with the U.S. Department of Agriculture, Gregory J. Weidemann, Director, Cooperative Extension System, The University of Connecticut, Storrs. The Connecticut Cooperative Extension System offers its programs to persons regardless of race, color, national origin, sex, age or disability and is an equal opportunity employer.