Technical Abstract: Applications of the codling moth granulovirus (CpGV), which target neonate larvae before or during initial entry into fruit, offer potential for selective control of this key pest. In field tests we compared the persistence and efficacy of single applications of three CpGV products approved for organic orchards in North America. In addition the success of repeated (2-14) applications of one product (Cyd-X) as a principal control measure for CM was monitored following operational use by cooperating growers at four separate locations. An early season application of label rates of all products remained highly effective (>80% larval mortality relative to controls) for 24 hours and moderately effective (>70%) for 72 hours during dry sunny conditions. Data obtained from commercial sites provides circumstantial evidence for the effectiveness of well-timed CpGV applications against CM outbreaks. In all cases where 1st generation larvae were targeted beginning at egg hatch and treated areas monitored (0.3 - 1.6 ha plots), fruit damage during 2nd generation was reduced or eliminated. Based on the number of live larvae recovered throughout the season, mortality rates remained high (80.3 ' 100% across sites). The cumulative number of moths caught in pheromone-baited traps was reduced (66-94%) in the second flight. Data from tree bands placed to catch diapause-destined larvae indicated overwintering generations in treated sites remained low (' 0.18 larvae/band).