Pheromone traps: A weakly effective synthetic female pheromone has been developed. It is too weak to use to detect flights of moths and so it is not available commercially. However, each year, we put out a few traps in walnuts, willows and oranges to detect the first flight of moths. Then we use degree day intervals to predict subsequent flights. See the management page for citrus peelminer for a more complete discussion. Fruit sampling: At the end of the season, we examine 1000 fruit per 10 acre block and determine the percentage with mines. This tells us how good our treatment program was. Treatments must be applied based on degree days and predicted moth flights, because if you wait till you see mining damage on the fruit, there is nothing you can do to fix it. Quite a bit of mortality occurs during the summer months because the larvae are on the fruit surface and it heats up.