Cypress tip miner—Argyresthia cupressella
The cypress tip miner is the most common Argyresthia pest of arborvitae, cypress, juniper, and
redwood in coastal areas of the West. Adults are silvery tan moths. Females lay scalelike eggs on green
tips. Eggs hatch into yellow or green larvae that feed on branch tips until late winter or spring. Larvae
spin slender, white, silken cocoons between the twiglets.
Foliage yellows in early winter, browns by late winter or spring, then recovers its green color during
spring and summer.
Provide proper cultural care to keep plants
vigorous. Prune out and dispose of foliage infested with
immature leafminers to restore the plant's aesthetic appearance
and provide some control. Consider replacing
plants especially susceptible to
the cypress tip miner. High populations and damage can be
plantings by applying a broad-spectrum, persistent insecticide
such as acephate on
susceptible varieties when adult moths are active. Beginning
spring, examine foliage tips for the cocoons. When these
appear, vigorously shake foliage and watch to see if silvery
tan, tiny moths fly up then settle
back on the foliage. One application to foliage can be made
when a large number of tip moths appear, between March and
May in California. This reduces browning next season.
Silvery tan adult tip miner
Browning of juniper caused by tip miner