Your Name - Bio 230


Control Tactics

Viburnum clearwing borer control includes many strategies to protect the shrubs typically preyed on by this wood burrowing bug.  Typically, the borer attacks trees weakened by damage, dryness and age (Cranshaw et al. 1999).  Therefore, simply maintaining the health of your tress can greatly reduce the probability of a borer attack.  Avoidance of damage from weed whackers, lawn mowers and poor pruning can be exercised when maintaining your landscape.  Other strategies include maintaining a watering schedule to prevent the shrub, and its roots, from drying out.  According to Cranshaw and Leatherman (1999), this is a vital practice when the eggs of the borer are laid and they are in season to hatch and tunnel into the roots of the plant.  Additionally, the use of landscaping mulch can deter and make it more difficult for a borer to reach the root zone.

Chemical strategies are often exercised during the adult moth egg laying life stage of the borer (Pellitteri 2004).  Unfortunately, larvae already underneath the bark of the plant are shielded from any chemical treatment available.  In order to properly time the onset of adult activity, Phil Pellitereri, from the University of Wisconsin – Extension Insect Diagnostic Lab, suggests the use of pheromone traps to monitor activity in spring. If you are unable to acquire pheromone traps to assist in determining when to spray, Pellitteri advises to spray initially mid June, and for heavy infestations reapply the treatment mid July.  A recent research study conducted by Hartman and Parson in 2005 attempted to record the flight patterns of the Virburnum borer in northeast Wisconsin.  With the use of pheromone traps placed throughout Brown county, observations found that the adult Synanthedon viburni  fly beginning in late May and continue to be present until early September in the Green Bay area (Hartman et al. 2005). 

Pellitteri also suggests that the pesticide used should contain insecticide Permethrin and should be sprayed from the ground level to approximately 18 inches up the shrub.  Hartman and Parsons also explored control options in their research study by planting four different sections of Virburnum plants at the Agriculture and Extension Services Center in Green Bay, Wisconsin (2005).  One of the four independent groups of plants were treated bi-weekly with a spraying of Permethrin insecticide, two rows were physically protected by tree wraps, and various tapes and aluminum foil, and one row was left untreated.  After a period of treatment and observation, Hartman and Parson concluded that applications of Permethrin during observed flight periods of May-August at 14-day intervals was statistically likely to keep shrubs free from borer invasion (Hartman et al. 2005). 

David Parsons, University of Wisconsin,

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