CULTURAL TIPS: PEST WATCH
While pest issues become less prevalent when cooler weather settles in, they still maintain an active
presence throughout October and early November in all California regions. However, the relative
abundance, amount of damage and insect type will vary between groves and districts. Therefore, the
most effective way to determine individual problems is to monitor your trees and make decisions
accordingly. It is suggested to keep a particularly close pulse on the following pests:
- Persea Mite: Persea mites (pictured to the right) feed on the undersides of leaves, along the midribs and veins, in nests protected by webbing. Feeding damage is evident by circular yellow - to dark brown - necrotic spots, resulting from the leaves' chlorophyll loss during feeding. Persea‐mite colonies generally begin increasing in midsummer, inflicting most damage by late summer, when defoliation of leaves with heavy‐feeding damage begins.
- Avocado Brown Mite: Avocado brown mites, which are closely related to persea mites, typically feed on upper‐leaf surfaces. Damage generally translates to bronzing of upper‐leaf surfaces, mite cast skin and partial defoliation. To read more about avocado brown mites, please click here: http://californiaagriculture.ucanr.org/landingpage.cfm?article=ca.v044n02p31&fulltext=yes.
- Avocado Lace Bug: Adult avocado lace bugs (pictured to the right) are small‐winged insects - about two mm in length (slightly longer than 1/16 inch) - with black bodies, yellow legs and antennae. Lace bugs limit feeding to the undersides of leaves, initially causing small, white - or yellow - spots on the leaves' surface. Heavy‐feeding damage is characterized by significant leaf discoloration, including dead, brown areas, shedded white skins on the undersides of leaves and early leaf drop. To read more about avocado lace bugs, please click here: http://cisr.ucr.edu/avocado_lace_bug.html. (Above information derived from AvoResearch newsletters & University of California, Integrated‐Pest Management (UC IPM) program)
Growers also should be aware of caterpillars, greenhouse thrips and glassy‐wing sharpshooters; although potential risk is not as severe as mites and lace bugs. For further information regarding the aforementioned pests, potential damage and control options, please visit the Grower website's Pest and Disease section - http://www.californiaavocadogrowers.com/pest-disease/ - the UC IPM website - http://www.ipm.ucdavis.edu/EXOTIC/exoticpestsmenu.html - or consult your Pest‐Control Advisor (PCA).