Monitor orchards weekly from early to mid-April through post petal fall to determine if citrus cutworm is a problem. The most critical period is late bloom to post petal fall when cutworm larvae are attracted to the small developing fruit. If populations begin to approach the threshold, monitor weekly until the population pupates. Before petal fall, the thresholds are 40 larvae per hour search and 10 to 15 larvae per 25 net shakes. During or after petal fall, the cutworm can cause more damage and the thresholds drop to 10 to 15 larvae per hour search and three to five larvae per 25 net shakes.
Timing is important because of short residual period.
Apply only during warm weather to control young, actively feeding worms. Use reduced wind velocity and drive 3 mph. Long, unless washed off by rain. Check label for variety. Use higher rate for larger worms and larger trees.