- Author: Anne Schellman
Beetles are the most plentiful of all insects on the planet, so it's understandable to get a few of them confused. Let's compare photos and other details about each of these beetles, and also mention the green June beetle, a beetle that is commonly mistaken for the Japanese beetle.
Japanese Beetles
Japanese beetles do not have an established population in California. The California Department of Food and Agriculture* (CDFA) maintains traps for detecting this pest throughout the state. When Japanese beetles are found in California, they are targeted for eradication (complete elimination). Read more about this invasive species on the UC IPM website at https://ipm.ucanr.edu/Invasive-and-Exotic-Pests/Japanese-Beetle/
Green Fruit Beetles
Green fruit beetles are a dull green color and much larger than Japanese beetles. You may notice them in late spring and summer as they zoom around your garden. Fortunately, they are rarely a pest. https://ipm.ucanr.edu/PMG/GARDEN/FRUIT/PESTS/grfruitbeetle.html
Rose Chafer Beetles
The rose chafer beetle resembles the hoplia beetle, however, this pest is not found in California. You can read more about these beetles on this informational page from University of Minnesota https://extension.umn.edu/yard-and-garden-insects/rose-chafers
Hoplia Beetles
Hoplia beetles are small, brown, and their undersides look like they've been dusted in gold. If you hold one in your hand, they will “play dead” and not move, making it easy to examine them.
You can read more details about managing hoplia beetles in the UC IPM Pest Notes: Hoplia Beetles.
*it's important that we help prevent invasive pests from taking hold in our communities and threatening agricultural crops. You can help by saying "yes" when trappers from the Agricultural Commissioner's Office ask if they can place traps in your landscape tree.
Anne Schellman is the Coordinator for the UC Cooperative Extension Master Gardener Program.
This article was originally published on May 8, 2023.
/h3>/h3>/h3>/h3>- Author: Elaine Lander
We've had many reports in the last two weeks from people asking what those big green, buzzing, beetles are. Green fruit beetles (Cotinis mutabilis) are members of the scarab beetle family and are sometimes known as fig beetles or figeater beetles. They are related to green June beetles (C. nitida) which are more commonly found in the South Eastern United States.
Green fruit beetles have a metallic green color and can be up to 1 1/3 inches long with prominent legs and antennae. The adults eat maturing soft fruit like figs and stone fruits, while the larvae (grubs) are found in compost or other decomposing matter. More on these occasional pests can be found on our website.
- Author: Karey Windbiel-Rojas
Originally posted August 26, 2016; edited July 10, 2018
Have you seen big green beetles in your California yard or garden? Or beetles feeding on your roses or other plants? There are many kinds of beetles commonly found in our landscapes, but the Japanese beetle is not one of them.
Japanese Beetles
Many people think they've seen the Japanese beetle, a small scarab beetle with metallic green wings with white spots on the margins. However, Japanese beetles are generally not found in California.
Green Fruit Beetles
Green fruit beetles are large beetles commonly found during spring and summer in California. While green fruit beetles are much larger than Japanese beetles and have different markings, these two beetles are frequently mistaken for each other. Adult green fruit beetles feed on ripe and overripe stone fruits, but damage is typically negligible so no control is necessary.
Beetles
Hoplia beetles are small, reddish-brown oval beetles that feed primarily on roses. They occur between March and May in California and tend to prefer feeding on light colored rose petals. For more information about hoplia beetles, see the Pest Notes: Hoplia Beetles.
Masked chafer grubs feed on the roots of turfgrass. Damage appears in late summer or fall as irregular patches of brown, dying grass.
When full grown, white grubs are about 1-inch-long, much bigger than some other lawn beetles. Read more about masked chafers and other lawn pests at http://ipm.ucanr.edu/PMG/PESTNOTES/pn7476.html
Be a Part of the Solution
/h2>/h2>/h2>/h2>
When people think of parasites, often what comes to mind are blood-sucking insects like bed bugs, head lice, and fleas or other bodily invaders on or in humans and other animals. But plants can have parasites too. Most of us are familiar with mistletoe but there is another parasitic plant you may not have heard about: dodder.
There are several species of dodder native to California but they are not as problematic as a particularly invasive species, Japanese dodder, Cuscuta japonica. This invasive plant pest has thick stems that resemble spaghetti. It grows larger and faster than native dodders and can even cover entire trees or shrubs.
Japanese dodder is spread when pieces of it are broken off and moved about by birds or other animals. It can also be spread through human activities such as pruning, composting, and the improper disposal of infected plant material.
For more information about Japanese dodder and other dodders, consult the Pest Notes: Dodder.
Hoplia beetle adults are small, reddish-brown scarab beetles that are often found resting inside a blossom. If you hold one in your hand, you'll notice that most of the body is a beautiful, iridescent silvery green color in the sunlight.
These beetles may also occasionally be found feeding on other plants with light-colored petals.
Some people believe they have the rose chafer or Japanese beetle in their landscape, however neither of these pests have populations in California.
Hoplia beetles are best managed using nonchemical controls such as handpicking. For more information on identification and management, see the UC IPM Pest Note: Hoplia Beetles.