The Spotted Lanternfly (SLF) is an invasive pest that poses a great threat to California's agriculture. It was first discovered in the U.S. in Pennsylvania in 2014 and has since taken the east coast by storm, causing damage to many plant species and proving to be difficult to control. Although this pest hasn't been found in California, it is important to keep an eye out to catch an invasion early.
What does the spotted lanternfly look like?
The SLF adult is about 1 inch in length with grayish wings, black spots, and red hind wings. Egg masses are laid in the fall on the east coast and resemble splotches of mud. They are often laid on smooth surfaces like branches, rocks, or outdoor furniture. Early nymphs are very small, wingless, and black with white spots. The last nymphal stage is 1/2 inch long and red with white and black markings.
What damage does the spotted lanternfly cause?
On the east coast, the spotted lanternfly's preferred host is the invasive tree-of-heaven (Ailanthus altissima), but it will also feed heavily on grapes, maples, willows, and birch trees. SLF feeds on plant sap and excretes honeydew, which can cause sooty mold to grow on leaves and fruit. It is known to kill black walnut saplings, tree-of-heaven, and grapevines. However, for most other plants SLF is considered a plant stressor and healthy plants can usually tolerate feeding.
What can you do to help keep the spotted lanternfly out?
Spotted lanternfly is easily transported to new areas as egg masses on firewood, stone, cars, and furniture. Check vehicles and trailers when traveling to areas where SLF has been confirmed. Inspect items purchased or shipped from these areas, and don't move firewood. Familiarize yourself with the various ways that SLF egg masses may appear and report any potential sightings to the CDFA Pest Hotline: 1-800-491-1899.
If you want to learn more, visit the UC IPM Spotted Lanternfly page and consider taking the California Master Gardener Spotted Lantern Fly training module.
- Author: Jan Merryweather, PlantRight
I saw Elvis today.
PlantRight defines “actionable awareness” as what happens when individuals and businesses are made aware of an opportunity to be part of the solution to California's costly (economically and environmentally) invasive garden plant problem, and make a conscious decision to act. Invasive plants (despite the fact that many are deceptively beautiful and drought resistant) outcompete native plants, alter soil chemistry, increase wildfire risk, clog our waterways and can severely compromise agricultural yields and real estate value. If that weren't enough, invasive species are the second greatest threat to biodiversity after human development.
Awareness of these facts alone will not fix any of these issues; however, add action to the mix and you have a proven formula for problem solving. PlantRight's idea of problem solving is collaborating with the industry to voluntarily phase invasive plants out of the supply chain and replace them with high-quality (i.e. non-invasive) plants. Voila! Together we prevent new invasive garden plants from wreaking havoc on our wild lands and taxpayer wallets.
The fact that 50% of California's invasive plants are of horticultural origin (Bell et al. 2007) is a source of both conversation and dismay. Yet from PlantRight's perspective this 50% is a great source of optimism because it's proof of a huge opportunity the nursery industry can play in preventing future invasive plant introductions. In past decades ornamental plant breeders and growers had little or no ability to predict a plant's invasive risk in a given region, and most invasions were well-intentioned accidents. Lucky for us we finally have science-based plant risk evaluation tools to prevent new invasive plant introductions. Not so lucky for us is that popular plants travel, and a delightful Dr. Jekyll plant in one region, may become a hideous Mr. Hyde plant and landscape transformer in a different region. It's about the right plant in the right place, but just where to begin, if we're to turn this talk into actionable awareness?
In the beginning there was lots of conversation and lots of listening sessions that Sustainable Conservation conducted with a diverse group of nursery industry stakeholders, from large ornamental growers, retail nurseries, plant scientists, trade associations and government agencies. University of California Agriculture and Natural Resources (UC ANR) has been part of this group from the start, providing academic expertise on weeds and calculating their risk. This group's official moniker is “California Horticultural Invasive Prevention,” but we prefer Cal-HIP.
With a couple years of listening and learning under our belts, and funding from Sustainable Conservation, the PlantRight program was ready for action: action engaging the nursery industry in voluntarily phasing our invasive ornamental plants and promoting, in their place, non-invasive alternatives.
Our first order of business was to measure the scope of the problem and establish a baseline. Working closely with plant science experts to identify the most problematic invasive ornamental plants, and industry experts to identify non-invasive alternatives, we created our first PlantRight plant list. If you can measure it you can manage it, we like to say - to do this, we rely on an annual Spring Nursery Survey. Each spring, partner with UC Master Gardener volunteers to survey more than 200 nurseries and garden centers around the state, and in the process track the retail market for invasive garden plants in California.
Along with informing PlantRight's program strategy, the annual survey allows us to keep PlantRight's plant list manageable and up to date – we add new invaders and retire those that are largely phased out of the trade. It is our program's calling card, and the starting point for conversations with prospective partners and skeptics, alike. It has earned the enthusiastic support of California Certified Nursery Professionals (CCNPro), SaveOurWater, and more.
A Little Less Fight, a Little More Spark
Buying non-invasive means many things, including protecting native species, being good stewards of our beautiful open spaces and waterways, being fiscally responsible and preventing additional taxpayer dollars going to avoidable invasive plant eradication efforts. Buying non-invasive plants is casting a vote for the kind of world you want to live in.
So, why on earth do people buy invasive plants in the first place? (Hint: One big reason has to do with what happens when you turn off the lights). Yep, people who purchased invasive plants were in the dark – they did not know.
In 2013, we learned that the primary drivers behind consumer purchases of invasive plants are: 1) aesthetics – it looks good; and, 2) there was no information on the plant indicating “invasive.” In other words the majority of invasive plant purchases (by consumers) are impulse purchases and would not have occurred had the plant been properly identified as “invasive.”
Come On, Come On…Come On, Come On
Ready to channel your inner Elvis and tackle invasive garden plant problems in ways that make economic sense? (Of course you are!) Here are a few resources to empower more action in your community.
- Share this article
- Sign up for the Spring Nursery Survey Webinar and Training
- View our Plant List at PlantRight.org
- Invasive Plant IQ Test
- View our 2016 Invasive Plants Webinar
- Little Less Conversation, Little More Action (Please) - Video
So this National Invasive Species Awareness Week we encourage you to crank up that volume and bust a move with the PlantRight community (blue suede shoes optional), knowing that YOU are driving actionable awareness…this week, this month and in the years ahead.
Thank you, thankyouverymuch.
- Author: Karey Windbiel-Rojas
Find out more about California Invasive Species Action week, species of concern, schedule of events, and what you can do to help prevent invasive species at https://www.wildlife.ca.gov/Conservation/Invasives/Action-Week.
The University of California has information about exotic and invasive pests on the UC IPM Exotic and Invasive Pests page and the Center for Invasive Species Research.
Also, read some of our recnt blog articles on invasive pests and their impacts in urban areas:
- Help Protect California's Citrus from Asian Citrus Psyllid
- Invasive Pests of Concern for California's Urban Farmers
- Bagrada Bug Continues to Spread in California
- Don't Grow Crazy: An Update on California's PlantRight Program
- Brown Marmorated Stink Bug
- Exotic Pests Invade California Landscapes
Once established, invasive species are extremely difficult to eradicate and can cause not only ecological disruption, but economic problems as well. Everyone has a part to play to keep exotic and invasive species from coming into California and spreading throughout the state.
