Lerps return, trees suffer

The red gum lerp psyllid has made its unwelcome return to Rancho Santa Fe, wreaking havoc on Ranch trees. The tiny insects appear every spring, said Pete Smith, Rancho Santa Fe Association manager.

“Every year their cycle seems to have a greater and greater impact,” Smith said.

The association plans to get an update at the June 18 meeting regarding the seriousness of this year’s problem.

The insect’s full name may be a mouthful, but they are actually very small insects native to Australia that suck sap from leaves of trees such as eucalyptus.

The insects cause leaf damage, heavy leaf litter and stress trees to make them susceptible to fatal attack by other insects. They also produce a sticky substance called honeydew, which residents may be noticing on the sidewalk or on their cars.

Rancho Santa Fe had a major problem with the insects in 2001, when the lerps feasted on trees on the west side of the Ranch. Director Bill Beckman said the west side is under attack again.

Beckman said a “shower” of leaves have been falling, leaving trees so stripped that it looks as though a fire came through.

“I’m really concerned we’ve got a huge problem here,” Beckman said.

Encrytid parasitoid wasps are a predator for the lerps. The United States Department of Agriculture Animal and Plant Health Inspection Service approved the release of the wasps at 13 Southern California sites in 2000. By 2003, the managed release of the wasps was discontinued, as the wasps were believed to have outnumbered the psyllid populations.

Pesticides are another option, but county entomologists have advised against their use in the past.

The damage to Ranch trees has more than just a negative aesthetic effect - dead and drying trees also pose a serious fire risk.

In a release, the Rancho Santa Fe Fire Protection District said that they’ve seen an increase in tree mortality attributed to the insects, drought conditions and in some cases lack of maintenance. As a result the district is focusing on working with homeowners to remove hazardous trees.

“We are absolutely not looking to remove all of the trees in the area,” Fire Marshal Cliff Hunter said in the release. “Rather, we are targeting only those trees that are clearly dead or dying. This will help minimize the fire hazard in the community and beautify the landscape.”

The district will be conducting an investigation of local trees and homeowners will be notified via mail if their infected trees need to be removed. Property owners with trees that have a lot of debris such as peeling bark or hanging limbs will also receive notices to clean them up.

The fire district will provide homeowners with potential tree removal companies or replacement tree suggestions.