January Bagworms

lawnagent

LawnSite Senior Member
A client called me to look at his shrubs and he has a major bagworm infestation going on with his evergreen shrubs. Now we have a fairly mild winter so far, but it is only mid January. I searched the threads but didn't find any for the proper method of control this time of year. What would be my best method of attack in January? Thanks!:)
 

turf hokie

LawnSite Silver Member
Location
Metro NY
My first line of attack no matter what time of year it is would be hand pulling.

Other than that, in your area,and this time of year, you would need to see what part of the lifecycle they are in and let that determine the direction you take.
 

fireman gus

LawnSite Senior Member
Location
Enid, Oklahoma
Our bagworm problem occurs in June. I have never heard of a problem this time of year. If you have a license you can spray with malathion, or if no license hand pick.
 

gharris1044

LawnSite Member
Location
Cary, NC
Even though you are seeing the bags now there is no new damage being done yet. The eggs are in the bags and when they hatch is when they can be treated. Chemicals won't penetrate the bags and they aren't feeding now so no need to treat. Best thing you can do is hand pick them and find out when they normally hatch in your area. When they hatch they are extremely succeptable to a lot of different insecticides. Even if you think you have hand picked them all you still need to spray because there can be 1 that you miss and each sack can hold 500-1,000 eggs!!
 

phasthound

LawnSite Fanatic
Location
Mt. Laurel, NJ
Even if you think you have hand picked them all you still need to spray because there can be 1 that you miss and each sack can hold 500-1,000 eggs!!
The reason bagworms lay so many eggs is because most of them do not survive to adulthood because they are eaten by predators. if you miss one or two sacks, you are providing a food source for the predator population which must remain to keep the pest in check.

Pesticide application is justified when the pest population is high and will cause damage. Continual pesticide applications for low level pest populations will develop pesticide resistance and increase the need for stronger pesticides. In other words, this is a band-aid approach which will fail over time.

Once you have handpicked before the eggs hatch and/or make an appropriate pesticide application, consider using the following method to maintain a balance which will keep the pest at low thresholds.


Plant Daisies to Fight Bagworms

The bagworm (Thyridopteryx ephemeraeformis) is a common pest of many coniferous and deciduous trees in the eastern U.S. This moth�s larvae spin unsightly baglike shelters in tree canopies and can cause serious damage through defoliation. Typical control methods include mechanical removal of the bagworm shelters (when feasible) and the application of pesticides. However, the bagworm has a number of natural enemies �in particular, parasitoid insects, such as ichneumonid wasps�and research at the University of Illinois at Urbana-Champaign has shown that bagworm control by these insects can be enhanced by planting certain flowering plants near trees and shrubs that are susceptible to bagworm infestations. The flowering plants used in the UIUC research were all members of the Asteraceae, or aster family, which includes many species with daisylike blossoms known to attract parasitoids. Among them were a shasta daisy cultivar (Leucanthemum � superbum �Alaska�), a cultivar of the Newfoundland aster (Aster novi-belgii �Professor Anton Kippenburg�), and the treasure flower (Gazania rigens), a South African native. The bagworm host plant was an arborvitae cultivar (Thuja occidentalis �Woodwardii�). In one trial, surrounding host plants with flowers led to a 70 percent increase in the parasitism of bagworms. In another trial, attacks on bagworms by parasitoid insects increased by a factor of three when host plants were surrounded by a high density of daisy flowers. Many plants in the Asteraceae are native to North America.

Source: J.A. Ellis et al., �Conservation Biological Control in Urban Landscapes: Manipulating Parasitoids of Bagworm (Lepidoptera: Psychidae) with Flowering Forbs,� Biological Control 34(1), July 2005, 99�107 (Elsevier Science, 6277 Sea Harbor Dr., Orlando, FL 32887).

Reprinted courtesy of Brooklyn Botanic Garden
 

dandd75

LawnSite Member
Location
Columbus OH
It seems that in the last few years the population of bagworms has exploded. We get them on the junipers the worse, and have found that when you pick them off in the winter( or shear the junipers in "bonsai" form as I do, thus cutting off the plant material the bags are on") and then treat with Conserve SC when the begin to emerge (May to early June here in OH) control is over 80 percent.
 

Snapper12

LawnSite Senior Member
Location
CE MO
Funny you mention this... last Friday night I was on a property putting down some salt for ice in the parking lot. I swung the truck around and the headlights lit up two Junipers that were covered in bags. The last time I was there was about a month and a half ago and there was zero on them. I had to take a picture.

Edit to add pic

bagworm-blanton.jpg
 

phasthound

LawnSite Fanatic
Location
Mt. Laurel, NJ
Funny you mention this... last Friday night I was on a property putting down some salt for ice in the parking lot. I swung the truck around and the headlights lit up two Junipers that were covered in bags. The last time I was there was about a month and a half ago and there was zero on them. I had to take a picture.
Sorry, but you just didn't see them before. http://insects.tamu.edu/fieldguide/cimg247.html
 

Top