Winter Moth

Winter Moth Integrated Pest Management (IPM)

Native to North and Central Europe, the Winter Moth was first introduced to “North America via Nova Scotia in the 1930s”, where it quickly became an agricultural pest (Childs et al., 2015, para. 3).  Although the moth is small - not even an inch long! - the caterpillars feed on deciduous plants that include cherry, blueberry, or as we have discovered here in our Seattle orchards, apples.   Because the caterpillars burrow and feed on both leaves and flower buds (para. 1), a large enough infestation could devastate an orchard.  Afterall, trees with damaged flower buds can’t produce fruit! 

Here in Seattle, we first noticed the extensive damage caused by Winter Moths in the spring of 2019. That year, the damage was so devastating that there was hardly any fruit to harvest in some of the orchards that we care for, including Jose Rizal Park which has seen the worst of the damage from these pests.

In November of 2020, in partnership with the City of Seattle’s Urban Food Systems (UFS), City Fruit rolled out a Winter Moth Integrated Pest Management (IPM) strategy that included treatment of 65 trees over 8 public Seattle orchards to assess pest presence in the orchards and implement a trapping control strategy. This included orchards at the Rainier Beach Community Center, Martha Washington Park, Amy Yee Tennis Center, Maple Wood Playfield, Danny Woo Community Garden, Meridian Playground, Burke-Gilman Trail, and Carkeek Park.

There is much we can learn from continued monitoring and research on the Winter Moth.  According to the Environmental Protection Agency, the IPM strategy “is an effective and environmentally sensitive approach to pest management” (EPA, 2015, para. 1).  The approach aims to use “current, comprehensive information of the life cycles of pests and their interactions with the environment” to guide and inform pest management decisions (para. 1).  For practitioners following an IPM strategy, the goal is to assess pest presence and implement prevention strategies first.  If prevention is no longer sufficient, then “less risky controls” such as trapping and weeding or pheromone sprays are implemented before any additional pest control strategies are put into place (para. 4-7).

Winter Moth is still new to our area, and we will continue to collect data and update this page with new findings.  

 

Interested in banding some of your own trees?

There are many different banding techniques that you might consider trying. However, if you are interested in the specific technique City Fruit used, take a look at some of the resources below.

Materials:

In general, you don’t need too many supplies to get started:

  1. Gloves to help manage the stickiness (cloth gloves are nice because they can be thrown in the washing machine)
  2. A roll of banding material (We used Tanglefoot® wrapping material: Tangle-Guard)
  3. Duct tape for securing the bottom of the band to the tree trunk
  4. A plastic applicator (putty knife or cake decorating spatula)
  5. A container of Tanglefoot® non-toxic insect barrier (it is very tacky, so take care not to get it on your clothes)

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Tips and techniques:

The tree banding process can be easily done by oneself.  However, if you are planning to band bigger trees with larger trunk circumferences, having an extra person handy can help the process!

  1. Estimating the length of banding material needed With non-gloved hands, take your roll of banding material and wrap the tape around the trunk of your tree about 4 ft. from the ground.  Cut or tear that section of banding tape off of the main roll.  You can then use that section of banding tape to measure out the length of duct-tape you will need to secure your band.
  2. Securing the band to your treeTaking the section of banding tape you prepared, wrap the tape back around your tree trunk.  Be sure to pull the banding tape taught so that it is as snug to the bark as possible.  Take your prepared section of duct-tape and use it to fasten the bottom edge of your banding tape to the bark of your tree trunk.  Fastening your banding tape with duct-tape helps prevent smaller moths from crawling under your band (some people might also put a layer of cotton underneath the banding for extra measure).  For larger trees, have a friend hold your banding tape taught while you fasten the duct-tape.
  3. Applying the Insect Barrier paste to your new band Using a cake spatula or a putty knife, apply the Insect Barrier paste onto your band.  The paste is pretty tacky and viscous, so working with smaller amounts is easiest.  It is also helpful to apply the paste in the direction in which you wrapped the band, so that you don’t accidentally pull the band loose when spreading the paste.  (See the Tanglefoot’s Tips for Success section below for considerations on coating thickness)
  4. Monitoring and replacing the band: It is important to monitor the band on at-least a weekly basis.  In places where Winter Moth infestation is high, bands can fill within the period of a few hours (Childs et al., 2015).  When the band’s sticky areas become filled with insect or plant-matter debris, remove and dispose of the original banding and replace with a fresh band.  If you are banding trees to capture adult Winter Moths, you will want to begin the banding process as early as October and maintain bands on trees until February (the end of the moths’ egg-laying period) (Faye, n.d.).

 

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The upper portion of this band is the Tangle-Guard banding material, and the bottom portion is the section of duct-tape used to secure the banding material to the tree.  Both the banding material and the duct-tape have been covered with a layer of Tanglefoot® insect barrier.

 

 

Tanglefoot’s Tips for Success

Here are more specific pointers and recommendations directly from Tanglefoot’s website:

“Tree Tanglefoot is oil-based and the oils will soak into the bark. Banding material eliminates staining of the tree and offers quick, complete removal of the sticky material. In addition, Tree Tanglefoot will remain sticky longer when applied on top of a surface resistant to oil. For rough bark trees it may be necessary to plug the gaps between the tree trunk and the banding, this can be done by using insulation or other materials.

“Apply Tree Tanglefoot Insect barrier in a uniform fashion. It can be applied in a heavy or light coat. Heavy coats are approximately 3" wide and 3/32" thick. A heavy coat is used when the insects kept from the tree foliage are large or numerous, or when there is little time available to maintain the band. Light coats are 3" wide and 1/16" thick. A light coat is good as a general barrier against smaller or less numerous insects, or when the band can be maintained regularly.

“Generally, Tree Tanglefoot will remain sticky and effective until it is covered with insects, dust or other debris. A build-up of debris or insects will create a bridge for other insects to cross. This debris requires removal and possible re-application in spots. If an area is unusually dusty or the surface of the barrier is stiffened, Tree Tanglefoot can be rubbed around to expose a new sticky layer beneath. Remove bands at end of season” (Tanglefoot, 2020).

 

References: 

Childs, R., Swanson, D., & Elkinton, J. (2015, March 6). Winter Moth Identification & Management [Text]. Center for Agriculture, Food and the Environment. https://ag.umass.edu/landscape/fact-sheets/winter-moth-identification-ma...

EPA. (2015, September 28). Integrated Pest Management (IPM) Principles [Overviews and Factsheets]. United States Environmental Protection Agency. https://www.epa.gov/safepestcontrol/integrated-pest-management-ipm-princ...

Faye. (n.d.). Do you need to worry about the winter moth? Russell Nursery. Retrieved January 12, 2021, from http://russellnursery.com/do-you-need-to-worry-about-winter-moth/

Tanglefoot. (2020). Tree Tanglefoot® Insect Barrier. Tanglefoot. https://www.tanglefoot.com/products/insect-control/tree-tanglefoot-insec...