ALB is Spreading
In 2004, Avocado Lace Bug was identified in backyard trees in Chula Vista and National City in San Diego County, probably originating from Mexico. Later in 2017, ALB was being picked up in the Oceanside, Fallbrook, and Temecula areas apparently originating from more Caribbean/Florida sources. That year, it also showed up in Long Beach and Culver City, and of the Mexican origin like in Chula Vista. Then in 2021, it showed up in Carpinteria, previously causing some major issues in Oahu, Hawaii that same year.
There has been some infill in the California infestations along the way, but it has not appeared to be as aggressive a spreader as persea mite or avocado thrips. Recently it was identified at a new site in Orange County. Mark Hoddle's lab at UC Riverside is following the spread and has helped in identifying where the infestations have been originating through DNA analysis.
Identification of ALB is quite easy since there are no other pests in California that it can be easily confused with. The first thing that usually draws your attention when looking for ALB is “islands” on the leaves. These necrotic regions develop because of the ALB adults feeding on the underside of the leaves and sucking the leaf juices from between the upper and lower leaf surfaces.
When the leaf is turned over, the adults, although only about 2 mm in length, are easily seen with the naked eye. Adults are oval, appear yellow to pale orange, and have dark heads. Nymphs are smaller than adults, oblong and are black, dark brown or reddish colored depending on their stage of development. Eggs appear as small black dots of varying sizes. What is visible is a dark sticky secretion covering the egg to protect it from predation. Under the sticky secretion, the eggs are oblong and yellowish.
Keep your eyes open for the damage and the pest, they are quite distinctive. The earlier it can be treated, the better the eventual control.