Preventing the destructive twolined spittlebug from devastating more crucial rangeland in the islands is the purpose of a new smartphone app developed by specialists at the University of Hawaii.

The free Twolined Spittlebug Tool app, available from the Apple Store and Google Play, creates a platform for people to report sightings of the invasive bug and helps them to make decisions about how to manage the pest.

The bug, named for the double lines on its back and its foamy secretions, has infested more than 176,000 acres of rangeland on Hawaii island. The twolined spittlebug sucks nutrient-rich juices from grass leaves and roots, and in highly infested areas has caused nearly 100% die-back of certain grasses important to livestock, said Mark Thorne, a state range and livestock extension specialist at UH Manoa.

Livestock producers have faced major economic losses, and the devastation has opened the land to invasive plants such as pamakani, wild blackberry and fireweed, Thorne said.

While at the moment the twolined spittlebug infestation is exclusive to Hawaii island, “we’re worried because we’re not sure how it got introduced into the Big Island. And so the other islands remain susceptible,” Thorne said.

The spittlebug’s damage affects Hawaii residents statewide because of its ripple effects on the economy, the environment and more, he added.

The app helps users to learn about the twolined spittlebug and distinguish it from two other types of spittlebug present in Hawaii. The app gives landowners the ability to locate, map and manage outbreaks on their properties. “Users can also assist experts as citizen-scientists by using the app’s reporting tool to geolocate sightings of the pest,” a UH news release said.

The app has four main features, Thorne said: “First, an information guide that provides an overview of TLSB (twolined spittlebug) biology and ecology. Next, it helps users identify TLSB in the field and distinguish it from other, nonpest species. Third, users can report sightings of TLSB. Fourth, it allows users to determine the size of the TLSB population, and then, based on the potential damage threshold calculated, select from a series of integrated pest management decisions.”

The UH team spent two years drafting content and working with developers to get the app released. A website displays a map of twolined spittlebug sightings reported by app users. More information and resources are available at rangelandsgateway.org/twolined-spittlebug.