Sapping cedars of their strength


Robert Chacon

Be careful where you catch some shade this summer.

An infestation of red spider mites is causing cedar deodar trees

-- the city’s second-most popular tree -- to defensively rain sap

droplets and shed needles.

Red spider mite infestations occur just about every year, but a

drought has weakened the tree’s natural defense against the

speck-sized insects, Public Works Director Steve Castellanos said.

When there’s more rain, the cedar deodar uses sap to create a

protective barrier against invaders, but because the trees are so

thirsty, they cannot produce enough sap.

Originating in the Himalayas, the cedar deodar looks like the

classic Christmas tree and can grow up to 70 feet.

Though spider mites do not generally kill the tree, an infestation

can weaken the trees and make them susceptible to other infestations

or diseases, said Rosser Garrison, an entomologist for the Los

Angeles County Agriculture Commission.

“Spider mites can decimate a tree because of their rapid

reproduction,” he said.

The most important step owners can take to protect their trees is

to immediately begin a deep watering cycle, Castellanos said. Owners

should place a water hose under a tree’s drip line, not next to its

trunk, and water for two to three days.

“Although it flies in the face of water-conservation efforts,

people should deep-water their trees once a month until the rainy

season,” Castellanos said.

Cedar deodar trees on city property are being sprayed with a

product that kills the mites but does not harm other plants or

insects. Homeowners should call a landscaping company to spray their

trees, experts recommend.

Owners who prune or fertilize their cedar deodar before cooler

weather arrives risk a lower expectation of survival for their tree,

Castellanos said.