The goal: To determine if Asian citrus psyllid (ACP) is in your grove and what impact the treatments you are applying have on ACP densities. Yellow sticky card traps are not very attractive to psyllids. Visual and tap sampling methods are better for population monitoring. Uniform sampling methods are used to compare infestations in commercial citrus orchards.
Sample 10 trees each on the east and south borders (rows/trees) of the orchard and in a center row of the orchard (total of 30 trees). The psyllid prefers borders and so the focus is on the outside edges of orchards. Edges are defined as breaks in citrus plantings, generally the size of a road. Enter the data on a sample sheet.
Visual Survey of Flush: The best way to find psyllids is to examine new soft leaves as they are developing and look for the nymphal stage with its waxy tubules. The adults must lay their eggs in new flush and so that is where they nymphs develop. The sampling procedure is simply to look carefully at terminals with new flush and count the number of nymphs per terminal in each of 10 trees on the SE borders and central rows.
Tap Sampling: Use a clipboard with a white piece of paper inside a plastic sheet. Spray the plastic sheet with a mixture of a squirt of detergent mixed in a ½ liter of water. ACP knocked onto the clipboard will stick in the solution, giving you time to see, identify and count them. Hold the clipboard under a branch and strike the branch 3 times with a 12” section of pvc pipe (or other device). Then count the number of winged adult psyllids collected on the clipboard. Wipe the psyllids off of the clipboard after each count and re-apply the liquid as needed. To see a video demonstration, click here Tap sample demonstration.
Flush status: Estimate the percentage of terminal branches that have feather flush or soft growing flush. This provides information about whether the flush is in a suitable state for psyllid nymphs to survive.