June beetles, also known as May beetles or June bugs, are nocturnal insects from the Scarab family.
These beetles are commonly found across North America and can be spotted in various colors, including dark brown, black, and even metallic green.
Considering their clumsy flying and attraction to nighttime lights, one may wonder if June beetles are blind.
While they don’t have the best vision among insects, June beetles are not completely blind.
Their attraction to light is likely due to positive phototaxis, a natural tendency for insects to move towards light sources.
Are June Beetles Blind?
June beetles are not blind; they do have eyes. However, their vision is not highly developed.
These beetles primarily rely on other senses, such as touch and smell, for navigation and finding food sources.
Despite their limited vision, June beetles are attracted to lights during nighttime.
They can often be found near porch lights or street lamps which may serve as a navigational aid for them.
June beetles are known for their clumsy movements both when walking and flying. This is due to their bulky bodies and less sophisticated vision.
Examples of their less-than-graceful movement include:
- Bumping into objects while flying
- Struggling to maintain balance when walking on uneven surfaces
Below is a comparison table with brief descriptions of June beetle characteristics:
|Sight Abilities||Limited vision|
|Attraction to Lights||Drawn to artificial and natural light sources|
|Clumsy Movements||Awkward walking and flying due to bulky body and poor vision|
Overview of June Beetles
June beetles belong to the genus Phyllophaga, which consists of around 260 species in North America.
They come in varying colors and sizes, with two well-known species being the Green June Beetle (Cotinis nitida) and the May Beetle, also known as June Bug.
The Green June Beetle is metallic green, nearly 1 inch long, and has bronze to yellow body margins.
On the other hand, the May Beetle can be black, brown, or tan, and usually measures between 0.5 to 1.0 inch long.
Distribution and Habitat
June beetles are mostly found in North America, stretching from the United States to Canada.
Their habitats range from forests to grasslands, and they are commonly sighted in both urban and rural areas.
The Green June Beetle is mostly found in the southeastern United States, whereas the May Beetle is distributed all across North America.
June Beetle Distribution:
- Green June Beetle: Southeastern United States
- May Beetle: North America
June beetles belong to the family Scarabaeidae, also known as scarab beetles. These beetles play a crucial role in the ecosystem by participating in nutrient cycles and pollination.
Life Cycle and Behaviors
Eggs and Larvae
June beetles lay their eggs in the soil, where they hatch into C-shaped larvae known as white grubs. These grubs are cream-colored with a reddish-brown head and three pairs of legs.
Some characteristics of the larvae include:
- Up to 1¼ inches long
- Feed on plant roots using their strong mandibles
Pupae and Adults
As the larvae continue to grow, they eventually enter the pupal stage. After pupation, June beetles emerge as adult insects. Adult June beetles have the following features:
- Oval, stout body
- Brown, rusty, or black color
- Hairy underside
- Clubbed antennae
While adult June beetles have wings, they fly clumsily and are primarily nocturnal.
Mating and Reproduction
Male and female June beetles find each other to mate.
During the mating process, both the male and female beetles engage in physical contact before eventually separating. After mating, females lay their eggs in the soil, beginning a new generation.
Comparisons between males and female June beetles
|Male June Beetles||Female June Beetles|
|Smaller in size||Larger, rounder in size|
|Eager to mate||Selective while choosing a mate|
Do June Beetles Cause Damage?
June beetles, also known as May beetles or June bugs, have various feeding habits depending on their life stage. Adult beetles primarily feed on foliage, while their larvae, known as white grubs, consume plant roots in the soil.
Effects on Plants
- Grubs can damage plant root systems, reducing their ability to absorb water and nutrients.
- Adult beetles can defoliate plants, leading to stunted growth or even plant death.
- Damage can occur on fruits, vegetables, and ornamental plants.
Apart from spoiling your lawns, June beetles can damage:
- Garden vegetables, such as carrots and radishes
- Fruits like strawberries, grapes, and raspberries
Both natural predators and chemical control measures can help in addressing June beetle infestations.
Methods to address infestations include:
- Encouraging natural predators, such as birds and nematodes
- Applying insecticides, if necessary, as a last resort
- Practicing good garden hygiene to reduce the likelihood of infestation
Please note that it’s important to consult local extension services for specific recommendations tailored to your area.
|Pros||Non-chemical control, helps maintain ecosystem balance||Non-chemical control, targeted approach|
|Cons||May cause additional damage to plants||Can be less effective in colder climates|
|Quick results||Potential harm to beneficial insects and environment|
|Broad-spectrum control||Possible resistance development in beetles|
June Beetles and Interactions with Humans and Pets
June beetles are nocturnal insects that are attracted to lights. This makes them a common sight near windows and doors.
Although they are not known to bite, their presence can be a nuisance for homeowners.
Generally, June beetles are considered harmless to humans and pets. They can become a food source for predators like birds or small mammals.
June beetles can cause damage to plants, especially their larvae, also known as white grubs. These grubs feed on plant roots and can lead to weakened or damaged lawns and gardens.
To reduce June beetle encounters around your home, try these prevention techniques:
- Window screens: Install screens on both windows and doors to keep beetles out.
- Seal gaps: Close any gaps around doors and windows to prevent entry.
- Reduce outdoor lighting: Lower the amount of bright outdoor lighting during peak beetle activity.
Comparing different prevention methods
|Window screens||Keep beetles out||Some installation effort|
|Seal gaps||Prevents entry||Requires inspection|
|Reduce outdoor lighting||Less attractive to beetles||May affect visibility|
If you’re troubled by white grubs in your garden, these guidelines are recommended:
- Monitor the area for damaged or weakened plants.
- Check for grubs in the soil around affected plants.
- Apply appropriate treatments, such as biological control agents or chemical insecticides, as needed.
Therefore, June beetles may be a nuisance around homes but are not dangerous to people or pets. Following the prevention methods mentioned above can help keep them under control.
Facts About June Beetles
June beetles can be found in various habitats like woodlands, forests, and grassy areas during late May and early June.
Some key features of June beetles include:
- Metallic green or dark brown color
- Noisy, snap-winging behavior
- Elytra: hard, protective forewings
- Around 0.5 to 1 inch in length
Examples of different types of June beetles include the Green June Beetle and Japanese beetles.
While Japanese beetles are known to cause damage to plants, Green June Beetles are considered beneficial in some instances, as they help break down organic matter.
Comparison between Green June Beetles and Japanese Beetles
|Green June Beetle||Japanese Beetle|
|Size||1 inch||0.5 inch|
|Color||Metallic green||Metallic green with copper-wing covers|
These beetles are also related to other insects, like roaches, and share some similarities in appearance. However, June beetles are distinct due to their hard elytra and characteristic snap-winging behavior.
The mystery of June beetle vision unveils a unique perspective on their behavior. While not blind, these nocturnal insects rely on senses like touch and smell, compensating for their limited vision.
Their attraction to lights arises from positive phototaxis, aiding their navigation.
With clumsy flight and movements due to their bulky bodies, June beetles continue to be a specimen of adaptations in the natural world.
Over the years, our website, whatsthatbug.com has received hundreds of letters and some interesting images asking us about these insects. Scroll down to have a look at some of them.
Letter 1 – Dusty June Beetle
Brown Gas Station Bug!
Location: North Hollywood, CA
June 10, 2011 2:46 pm
Hi Bugman (bugpeople?),
I found this bug at a gas station yesterday in North Hollywood, CA. It looks big in the photo, but I’d say it was the size of a large jellybean.
It was alone, sitting on the ground, and just asking to have it’s picture taken! Someone suggested it might be a Christmas beetle, but I looked that up, and it seems shinier than the bug I found.
Thanks for your knowledge!
Signature: Jeffrey Mann
Christmas Beetles are from Australia, and that is not to say that they might be introduced to southern California like many other other Australian insects, however, we believe this is another scarab known as a Dusty June Beetle in the genus Amblonoxia.
According to Charles Hogue in his wonderful book, Insects of the Los Angeles Basin, the Dusty June Beetle can be recognized by its “heart-shaped scutellum” which is “noticeably paler than the rest of the back.” More photos are available on BugGuide.
Letter 2 – Another Ten Lined June Beetle in Mount Washington
Subject: Look at who died on my terrace
Geographic location of the bug: Mount Washington, Los Angeles, California
Time: 03:03 PM EDT
Your letter to the bugman: It’s so beautiful I took a pretty shawl to show him off.
How you want your letter signed: Monique
Good Morning Monique,
This is a Ten Lined June Beetle, Polyphylla decemlineata, and Daniel spotted one about two weeks ago on his screen door.
Though quite common at higher elevations in Pasadena and La Cañada, Daniel did not make a Mount Washington sighting of a Ten Lined June Beetle until 2015 and he has seen them yearly ever since. According to Charles Hogue in Insects of the Los Angeles Basin: “Adults feed at night on the needles of coniferous trees.”
Letter 3 – Bug of the Month July 2013: Ten Lined June Beetle
Subject: What’s this Stripey Beetle
Location: Carmel Valley, CA
June 25, 2013 10:50 pm
Hello – this cute fella was hanging on my screen at 10:30pm and seems to have had a lucky escape as there was spider web on one foot. About an inch long, white and green striped beetle with brown ”really cute” face. Very mellow and gentlemenly.
This impressive beetle is a Ten Lined June Beetle, Polyphylla decemlineata, a large Scarab Beetle that is found throughout much of western North America. According to BugGuide: “Adults feed on tree foliage; larvae feed on roots of shrubs/trees.” Adults which fly during midsummer are attracted to lights and they make a squeaking sound known as stridulation when they are handled.
Even though the common name indicates they are found in June and your specimen was found in June, and even though the subfamily they belong to, Melolonthinae, is commonly referred to as May Beetles, we have selected your submission as the Bug of the Month for July 2013 since they are most commonly sighted in July.
Thank you so much as I really enjoyed him and now learning about him. Honored to be the Bug of the Month!! You have a very cool site.
Comment: July 24, 2013 12:13 pm
I’m so happy to have found your website! Thank you for making the Polyphylla decemlineata your July Bug of the Month. We have one of these delightful fellows in our backyard and his behavior is quite baffeling. We find him on his back every day or so, and think he must be dead.
Then later in the day or the next we seem him walking about. Do they sleep on their backs? We jostled him a bit one day, thinking he was dead, and his legs wiggled. We turned him over and he walked away.?…
We aren’t certain why you keep finding Ten Lined June Beetles on their back, but sometimes beetles fall that way and it takes them some time to right themselves.
Letter 4 – Fig-Eater or Green June Beetle
Could you please help me identify beetle. The beetles were flying around the garden in Pennsylvania. This beetle was twice the size of the Japenese beetles that were also present.
This is a Fig-Eater or Green June Beetle, Cotinis nitida. Adults visit flowers especially hollyhocks as well as ripening fruit. They are very fond of peaches. They occasionally form swarms of great size and buzz loudly.
Letter 5 – 10 Lined June Beetle
Subject: 10 Lined June Beetle
Location: Mount Washington, Los Angeles, California
July 2, 2016
Ten Lined June Beetles started appearing at the What’s That Bug? office just last year. Our only interaction with them before that was the pine habitat in higher altitude Pasadena and La Cañada. This lady, who has much smaller antennae than the male who needs to be able to sense her pheromones, appeared on our screen door late last night and we got some flash assisted images today.
We are perfectly happy if she wants to wait on our screen door until a suitable suitor arrives. The 10 Lined June Beetle we found in June was already dead, and we suspect porch and garage lights are attracting them. She stridulated (began squeaking by rubbing together parts of her body) when we picked her up to move her higher up on the screen door in the event marauding raccoons are on the prowl tonight.