You may have noticed swarms of flying insects landing on your roses, calla lillies, hydrangeas, and other flowers. If you look closely, you'll see the insect inside the flower, and the chewing damage on the petals. These pests are hoplia beetles, but are often misidentified as Japanese beetles or rose chafer beetles.

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.

The best way to manage hoplia beetles is to regularly handpick or shake them off flowers into a bucket of soapy water and then dispose of it. This can help reduce beetle populations in the future. You can also fill white, 5-gallon buckets with water and a few drops of detergent. The white color may attract the beetles which will fall into the bucket and drown. Using a pesticide to spray the beetles is not recommended, as it does not work. Hopefully by June, hoplia beetles will have completed their lifecycle and disappear from our gardens.

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.

 

“These trees which he plants, and under whose shade he shall never sit, he loves them for themselves, and for the sake of his children and his children's children, who are to sit beneath the shadow of their spreading boughs.”

Author: Hyacinthe Loyson

I love to wander among trees, to see and hear the leaves swaying in the breeze, observe birds darting about the branches, squirrels running up and down the trunk, and insects flitting about. I have spent many contented hours sitting under a tree reading a good book. Trees mark the seasons of our lives, blooming in the spring before producing green leaves, producing fruits or nuts in the summer, changing colors in the fall, standing bare and stark during the winter months. I particularly love the Valley Oak tree (Quercus lobata) with its distinctive lobed leaves, the acorns it yields, the fascinating oak galls produced by tiny wasps, and their historical importance to the original people of California as a staple food source.

Arbor Day

Along with 50 countries around the world, the USA celebrates trees on Arbor Day. The day is celebrated during the spring tree planting season. In the USA, the date is typically the last Friday of April, which this year was Friday, April 26. The date varies around the world depending on geography, weather, and if in the Northern or Southern Hemisphere.

But why do we commemorate trees and how did Arbor Day get started?

Benefits of Trees

From the beginning, trees have provided us with the oxygen we breathe, along with food, shelter, medicine, and tools. To list a few of their other benefits:

• Trees help combat climate change – Trees absorb carbon dioxide (CO2), which is contributing to global warming. They remove the CO2 from the air and store the carbon. In one year, an acre of trees can absorb the same amount of CO2 produced when the average car is driven 26,000 miles.
• Trees clean the air – Trees absorb odors and pollutant gases such as nitrogen oxides, ammonia, sulfur dioxide and ozone and filter particulates out of the air by trapping them on their leaves and bark.
• Trees provide habitat for wildlife – Sycamores and oaks are among numerous trees that provide homes for many species of birds, mammals, insects, amphibians, and reptiles.
• Trees cool cities – Trees deflect the sunlight, cooling the air up to 10°F by shading our homes, buildings, and roads.
• Trees prevent soil erosion – Trees reduce water runoff by allowing the rainwater to flow down the trunk, onto the earth below. Their roots also slow runoff and hold the soil in place.
• Trees provide wood and paper – Trees help us build our homes and the paper we write on.
• Trees beautify urban spaces – Trees can mask unsightly concrete walls, parking lots, and unsightly views. They help muffle the sounds of the city and create eye-soothing canopies of green. They absorb dust and reduce glare.
• Trees provide personal and spiritual values – During our busy lives, trees can give us a piece of nature and moments of tranquility.

Arbor Day History

“Arbor” literally translates to “tree” from the Latin word arbor. The origins date back to the early 1870s to Nebraska City. Julius Sterling Morton and his wife, Caroline, planted a wide variety of trees on 160 acres of what was then a flat stretch of prairie. Through his job as editor of the state's first newspaper he spread his knowledge of trees, extolled their importance to the state of Nebraska by reforesting the empty plains. Morton proposed to the Nebraska Board of Agriculture that a day be designated to encourage people to plant trees. The first Arbor Day was held on April 10, 1872. The day was a huge success with approximately 1 million trees being planted.

The tradition quickly spread and within 20 years the day was celebrated in every state but Delaware. On April 15, 1907, President Theodore Roosevelt, a conservation supporter, issued an “Arbor Day Proclamation to the School Children of the United States.” In 1970, Arbor Day became nationally recognized due to efforts by President Richard Nixon.

People can celebrate Arbor Day by planting a tree (which can be dedicated to a loved one) and spending time caring for the trees we have. Morton's words resonate strongly today as climate change becomes a serious threat: “Other holidays repose on the past: Arbor Day proposes for the future.”

How Can We Help?

Some of the ways we can help preserve trees are:

• To reduce the demand for paper, check out books from your local Stanislaus County Library instead of purchasing new ones.
• Help protect existing forests – Encourage reduced cutting down of healthy forests by supporting sustainable reforestation.
• Afforestation – Support the planting of new forest plantations, which can enhance existing forest cover and help reduce global warming with carbon sequestration.
• Continue to water your tree, even during a drought. If you shut off lawn water, don't forget to deep water your tree! You can use a hose or soaker hose to water under the drip line.
• And, of course, plant a tree! You can volunteer for local organizations when they have tree planting days or plant a tree in your garden.

An excellent resource on care and selection of trees is Stanislaus County's Master Gardener “Trees in Your Home Garden,” https://ucanr.edu/sites/CEStanislausCo/files/341553.pdf

Additional resources include on how to plant a tree: https://ucanr.edu/sites/UrbanHort/files/80160.pdf, and on pruning trees: https://ucanr.edu/sites/UrbanHort/files/80116.pdf

Favorite Tree?

Do you have a favorite tree? Write in our comment section what your favorite tree is and why?!

Denise Godbout-Avant has been a UC Cooperative Extension Master Gardener in Stanislaus County since 2020.

This article was originally published on April 25, 2022.

When: Saturday, May 4, 2024 from 9:30 a.m. -12:00 pm 
Cost: $30
Location: emailed to participants.
Instructors: UC Cooperative Extension Stanislaus County Master Gardeners Roxanne Campbell, Rho Yare, and Sandy Mann.
Sign Up: Space is limited, register by paying online at https://ucanr.edu/succulents/2024

If you can't pay by credit card, we will accept cash or check if paid before May 1, 2024. Email aschellman@ucanr.edu or call (209) 525-6800 and ask for Anne to arrange to pay ahead.

This class does not accept walk-ins, payment must be made ahead of time.

Water Is a Precious Resource

Earth is known as the “Blue Planet” since from space one can see it is about 71% covered with water. However, about 99% of that water is either ocean salt water or saline water. Less than 1% is freshwater and much of that freshwater is trapped in glaciers or underground where it is inaccessible. About 50% of the available freshwater stays in rivers for nature. The other half of the 1% freshwater is for human consumption.

To put all those numbers in perspective*, imagine a five-gallon bucket of water. Of that five-gallon, only ONE DROP is freshwater that is available for human use and most of that goes to agriculture to put food on our tables, which does not leave much for our homes and gardens!

California is no stranger to drought. It is a recurring feature of our Mediterranean climate but due to climate change drought is expected to happen more frequently and with longer, more extreme. Which will lead to years when we have even less available freshwater. So, we must learn to incorporate water sustainability into our everyday lives.

Learn About Water Sustainability in Our Gardens

During the month of May, the Stanislaus County UC Master Gardeners will be giving talks on Waterwise Landscaping at county libraries. Some ways to conserve water include changing from sprinklers to drip irrigation, reducing lawns, and using the right plant in the right place. Even small changes can lead to meaningful water savings. Master Gardeners will be discussing these methods, as well as how soil types determine how much water to apply, the value of mulching, how to reduce water runoff, hydrozones, and suggestions for attractive waterwise plants that grow well in our area.

With water being such a precious resource, we must make the most of every drop. We hope to see you at a local library for one of our classes. Come and learn water conservation methods you can incorporate in your garden.

You can also visit our website calendar for a full list of classes with dates, times, and locations at https://ucanr.edu/sites/stancountymg/Calendar/

*visit our YouTube Channel to watch a hands on demonstration of Denise explaining how much fresh water exists on our planet. Teachers, the video is 2 1/2 minutes long, so feel free to use in your classrooms!