Leafrollers are a group of moth larvae that attack a variety of plants, including fruit and ornamental trees, by rolling leaves into protective shelters where they feed. They are widespread throughout North America and can cause significant damage if left unchecked. Some common species include the obliquebanded leafroller (Choristoneura rosaceana) and the fruittree leafroller (Archips argyrospila).
These leafrollers can feed on several plants in the Rosaceae family and many other species, causing damage that can impact fruit production or the overall health of the plant. For example, the fruittree leafroller is known to affect deciduous and live oaks, as well as other ornamental trees such as ash or maple. By understanding their biology and habits, gardeners and farmers can take appropriate measures to prevent and control leafroller infestations.
Leafroller Identification
Leafroller Species
There are several species of leafrollers that can be harmful to plants, including:
- Fruittree leafroller (Archips argyrospila)
- Obliquebanded leafroller (Choristoneura rosaceana)
- Pandemis leafroller (Pandemis species)
- European leafroller (Archips rosanus)
Each species has its unique characteristics and impact on plants but share some common traits in their life stages.
Larvae
The larval stage of leafrollers is considered the most destructive. Larvae are typically:
- Green or pale green in color
- Slender in shape
- Varying in length, depending on the species
For example, the larvae of the obliquebanded leafroller can grow up to 1 inch long.
Pupae
Leafroller pupae generally share the following characteristics:
- Found within rolled leaves or other protected areas
- Develop in spring or late summer, depending on the generation
Adult Moths
Adult leafroller moths have some common traits across species:
- Brown or dark-colored wings
- Proportional sizes based on larval stage lengths
- Distinct wing patterns
| Species | Wing Pattern |
|---|---|
| Fruittree leafroller | Thin light markings in various patterns across the front wings |
| Obliquebanded | Bands darker than the rest of the wing on the leading and trailing edges |
| Pandemis leafroller | Similar to obliquebanded, but leading and trailing edges of bands are lighter |
| European leafroller | Lighter brown than other species, pronounced forewing markings |
These identifying features can help you determine the leafroller species affecting your plants and take appropriate control measures.
Life Cycle and Feeding Habits
Egg Development and Hatching
Pandemis and oblique-banded leafrollers lay eggs in masses on the upper surface of leaves. Hatchlings emerge once temperature and humidity conditions become favorable:
- Masses contain 50 to 300 eggs
- Eggs hatch in approximately 7 to 14 days, depending on environmental factors1
Feeding on Leaves and Fruits
Young larvae prefer to feed on new foliage, while older larvae also target fruits in various stages of development. Their impact varies depending on tree size and type:
- Large trees may have 2 to 10 times more larvae in the upper half than the lower half2
- Spur varieties often experience more concentrated feeding damage3
Overall, different tree types and feeding habits affect the distribution of leafroller larvae and the extent of the damage they cause.
Footnotes
Reader Emails
Over the years, our website, whatsthatbug.com has received hundreds of letters and some interesting images asking us about these insects. Scroll down to have a look at some of them.
Letter 1 – Oak Leafrollers: Caterpillars drop from trees in Florida
What is this?
Location: St. Petersburg, FL
March 7, 2011 2:58 pm
We’ve been seeing many of these drop from our trees recently (mostly from oak trees). In the past few days there have been hundreds around our house and we’ve been seeing them drop from trees all over the neighborhood this weekend. They are green, with a black head and appear to be some sort of larvae but not sure. Some are really tiny while others more than an inch long. They drop down on a silk-like thread so it now looks like we have spider webs all over. Any idea what they are, or what they will become?
Signature: Greg
Green caterpillers
Location: St. Petersburg, FL
March 14, 2011 10:52 am
I recently sent in a picture of green worm looking bugs that hang on a thread of silk from our Oak trees. I just came accross this new item about them.
Caterpillars invade Tampa Bay!
http://www.wtsp.com/news/local/story.aspx?storyid=179758
”Jane Morse, with the Pinellas County Extension says the caterpillars are the larvae of either oak leafrollers or oakleaftier moths”
Just wanted to let you know!
Signature: Greg
Dear Greg,
We apologize for not writing back to you. We had every intention of trying to identify this caterpillar phenomenon, but we got very busy with a personal matter. We are very happy you wrote back and provided a link to a news story on the Oak Leafroller or Oakleaftier Moth Caterpillars. Unfortunately, Jane Morse did not supply a scientific name for the Oak Leafroller or Oakleaftier Moths, but we did locate a Texas A&M Agricultural Extension Service webpage article that has some great information. BugGuide provides the scientific name Argyrotaenia quercifoliana for the Oak Leafroller.
Letter 2 – Oak Leafroller
Caterpillar?
Location: Central Florida
March 5, 2011 8:01 pm
Hi!
Just a few weeks ago we started getting these little worm-like bugs all over our house/trees. Now normally it’d be fine, we’re not freaked out by bugs or anything but they are EVERYWHERE. We can sweep them off the porch/cars and the next morning there’s just as many if not more. I tried looking them up but can’t find any that actually look like them, I’m not sure if they’re just babies, or what. Friends were talking about killing them/hosing them down/etc but I don’t want to harm them if they’re useful/pretty.
Signature: Anna Moore
Hi Anna,
Another reader just supplied us to a link entitled “Caterpillars Invade Tampa Bay” that provides information on the Oak Leafroller, Argyrotaenia quercifoliana, and other similar Caterpillars that are currently being reported in great numbers in Florida.
Reader Emails
Over the years, our website, whatsthatbug.com has received hundreds of letters and some interesting images asking us about these insects. Scroll down to have a look at some of them.
Letter 1 – Omnivorous Leafroller
cool shaped moth
June 26, 2010
Hi. I found this guy near a light and thought the shape of his wings was really cool. Thanks to Kaufman’s guide (which I got on your recommendation) I think it might be Archips purpurana, an omnivorous leafroller. What do you think?
Sara
New Jersey
Hi Sara,
We are happy that our recommendation of the Kaufman’s Guide has been helpful for you. It seems you nailed the ID on the Omnivorous Leafroller, Archips purpurana, but according to BugGuide, it is: “known as Omnivorous Leafroller but that name is more commonly applied to another species, Platynota stultana, and is therefore confusing.“
Well they are dropping in south Florida right now. They are everywhere!
We just posted a report from Texas of a completely different caterpillar, in our estimation a Spanworm in the family Geometridae, that is also appearing in large numbers and dropping from trees.
These are everywhere all over my house my shrubs { their eating } I don’t care what they are what kills them- I have 4 different types coming out of the oak trees.