June Beetle

June beetles are troublesome pests that can cause significant damage to your lawn and garden. They come in various colors and sizes, with one common example being the green June beetle, which can grow nearly an inch long and have a metallic green appearance. These beetles can wreak havoc on plants, fruits, and the root systems of your lawn, making it essential to find effective ways to get rid of them.

There are several methods to rid your yard of these pesky beetles, ranging from manual removal to using more targeted approaches. For example, it’s possible to reduce their numbers by shaking beetles off plants when they’re sluggish, such as early in the morning, and submerging them in soapy water to kill them.

While the physical removal of June beetles can be effective, it may not always be the most efficient approach. Some alternatives include using insecticides, introducing natural predators, or setting up traps to capture the beetles. Each method has its pros and cons, which should be evaluated based on the size of your beetle infestation and the specific needs of your lawn and garden.

Identifying June Beetles

Physical Characteristics

June beetles, also known as June bugs, are medium to large-sized beetles typically brown in color. They have a noticeably oval shape and hard exoskeletons. Here are some key features of June beetles:

• Oval-shaped body
• Brown or reddish-brown in color
• Hard exoskeleton

One of the most common physical traits is their size, usually ranging from 0.5 to 1 inch in length.

Common Species

There are several species of June beetles, each with minor variations in appearance and behavior. Some common species include the green June beetle and the May or June beetle.

Green June Beetle

The green June beetle (Cotinus nitida) is a large, metallic green beetle measuring around 1 inch long. It has bronze to yellow body margins and reddish-brown wing covers. This species is known for hunching across the ground on their back legs.

May or June Beetle

The May or June beetle has a more typical brown color and varies in size. While their larvae feed on grass and other plant roots for 2 to 3 years, adult beetles emerge during May or June, giving them the name May or June beetle.

Here’s a comparison table for these two common species:

June Beetle Life Cycle

Eggs

June beetle eggs are laid in the soil during May or June. They hatch in June to early July, allowing the larvae to begin feeding on grass, broadleaf weed, tree, and shrub roots ¹.

Larvae and Grubs

The larvae, also known as white grubs, feed on roots during their development. The larval period varies, lasting 2 to 4 years depending by the site and the growing season ². Younger grubs live deeper in the soil while older grubs can be found closer to the surface, feeding on woody roots.

Here are the main characteristics of June beetle larvae and grubs:

• Cream-colored
• Grow from 1/4 inch to 2 inches long ³
• Feed on various plant roots

Pupa

June beetle larvae pupate in early June, transforming within the soil before emerging as adults ⁴.

Adult Beetles

Adult June beetles emerge from the soil between late June and the middle of August. Upon emerging, they tend to gather in large numbers, congregating on shrubs and trees ⁵. Adult beetles are attracted to lights and are most active just before and after sunset during May or June ¹.

Some features of adult June beetles are:

• Metallic green color
• Nearly 1 inch long
• Bronze to yellow body margins
• Sometimes reddish-brown wing covers ³

Comparison of June Beetle Life Stages:

June Beetle Damage to Plants and Lawns

Garden and Lawn Damage

June Beetles can cause significant damage to gardens and lawns. Adult beetles are known to injure turfgrass, mainly during May and June¹. These beetles lay their eggs in June and early July, and the hatched larvae feed on grass and broadleaf weeds¹.

Some noticeable signs of June Beetle damage include:

• Brown patches in the lawn
• Thinning grass
• Damaged leaves on garden plants

Tree and Shrub Damage

Tree and shrub damages are also caused by June Beetle larvae¹. They can feed on the roots and leaves of trees and shrubs, causing defoliation and weakening the plant’s overall health⁴.

For example, the Viburnum leaf beetle specifically targets Viburnum plants, causing holey leaves and significant damage³.

Comparison Table: Garden and Lawn Damage vs. Tree and Shrub Damage

Methods to Control June Beetles

To mitigate the damage caused by June Beetles, you can:

1. Remove beetles manually by shaking them off plants and killing them in soapy water².
2. Use cheesecloth or fine netting to protect high-value plants².

Pros:

• Environmentally friendly
• Low cost

Cons:

• Time-consuming
• Labor-intensive

Natural and Organic Control Methods

Predators and Beneficial Insects

Some predators help control June beetle populations:

• Birds: They eat adult beetles and grubs.
• Toads: They feed on adult beetles.

Introducing beneficial insects can also mitigate these pests. For example, certain nematodes can attack June beetle grubs.

Neem Oil

Neem oil is a natural and organic solution derived from the neem tree. It repels June beetles and can prevent egg-laying.

Pros:

• Eco-friendly
• Non-toxic to beneficial insects

Cons:

• Requires repeated applications
• May not eliminate beetles entirely

Milky Spore

Milky spore is a bacterium that specifically targets June beetle grubs. It causes a disease that kills the grubs, eventually reducing the adult beetle population.

Pros:

• Environmentally friendly
• Long-lasting effect

Cons:

• Takes time to show results
• Needs proper application

Nematodes

Beneficial nematodes are microscopic worms that attack and kill June beetle grubs. Introduction of these nematodes can reduce populations.

Pros:

• Safe for the environment
• Targets multiple pests

Cons:

• Requires specific soil conditions
• Can be affected by pesticides

Comparison Table

Trapping and Deterrent Methods

Physical Traps

One way to catch June beetles is by using physical traps. Commercially available beetle traps can be an effective method to control the beetle population. Some examples include:

• Bag-A-Bug
• Tanglefoot

Remember to:

• Clean traps every 2 days
• Set traps away from your favorite plants

Light Traps

June beetles are attracted to light, especially at night. You can use light traps to lure and catch them. Here’s an example of a simple light trap setup:

1. Hang a bright light (e.g. LED, incandescent)
2. Place a container with soapy water underneath

Make sure to:

• Turn off unnecessary outdoor lights
• Close doors and windows to prevent beetles from entering your home

Homemade Traps

You can save money by creating a homemade June bug trap. One popular method involves using a jar and a piece of fruit. Here’s how:

1. Place a piece of ripe fruit (e.g. banana) inside a jar
2. Poke small holes in the lid for beetles to enter
3. Seal the jar and leave it out at night

The beetles will be attracted to the fruit and trapped inside the jar.

Pros:

• Inexpensive
• Environmentally friendly

Cons:

• May require regular maintenance
• Less effective than commercial traps

In summary, it’s important to choose the best trapping and deterrent method for your specific situation and preferences. Remember to maintain proper trap hygiene and always follow safety guidelines while handling beetles.

Chemical Treatments

Insecticides

Insecticides are a common method to control June beetle infestations. The best time to apply these is during the larvae stage when they are most vulnerable:

• Example: Products containing carbaryl or imidacloprid can be effective.

Pros:

• Fast acting
• Can target various stages of beetle development

Cons:

• Harmful to beneficial insects

Fertilizers and Pesticides

Incorporating specific fertilizers and pesticides into your soil can help deter June beetles. These products disrupt their feeding patterns:

• Molasses: Amend soil with molasses to make it less hospitable for beetles.
• Example: Apply a pesticidal mix containing nematodes to target larvae.

Pros:

• Improves overall soil health
• Sustainable option

Cons:

• May require multiple applications

Comparison Table:

Commercial Beetle Traps

Commercial beetle traps are effective in capturing adult beetles and reducing their population:

• Example: Traps that use pheromones or light to lure beetles.

Remember to:

• Clean traps every 2 days
• Place them away from your favorite plants

Pros:

• Easy to use
• Non-toxic

Cons:

• May attract more beetles to the area

Tip: Combine chemical treatments with non-chemical methods like hand-picking or netting for better results.

Preventative Measures for June Beetles

Landscape Maintenance

• Regularly mow your lawn
• Water your garden effectively

Proper landscape maintenance helps keep June beetles at bay. For example, regularly mowing your lawn ensures the grass stays at a healthy height, which discourages beetle occupation. Watering your garden effectively, preferably in the morning, prevents excess moisture accumulation, as beetles thrive in moist conditions¹.

Reducing Attractive Habitat

• Limit the use of mulch
• Use physical barriers on high valued plants

Creating an environment unwelcoming to June beetles, like limiting the use of mulch around roses and other foliage, can reduce their presence in gardens². Placing physical barriers, such as cheesecloth or fine netting material, on high valued plants helps protect them from beetle infestations.

Timely Treatment

Timely treatment is crucial in controlling June beetle populations. Two treatment options include beneficial nematodes and insecticides, which can be applied during spring and fall seasons³. Both options target underground larvae, preventing them from maturing into adults.

Pros of Nematodes:

• Environmentally friendly
• Targets multiple grub species

Cons of Nematodes:

• Requires proper storage conditions
• Might need a specific nematode species for best results

Pros of Insecticides:

• Effortless application

Cons of Insecticides:

• Potential environmental impact
• May require multiple applications

Reader Emails

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 – Ten Lined June Beetle

Potato Bug?
Location:  Northern Nevada
September 5, 2010 8:51 pm
I’m really just out to be sure this is what I think it is. It’s the second time I’ve found this bug. The first time was South Lake Tahoe California and this time, it’s Carson City, Nevada. I think this big hissing fellow is a Potato bug, but I want to know what variety. I know he’s not a Colorado Potato Bug – wrong markings for that guy, but as I can’t remember exactly where I found info on him before, I’m hopeful you’ll be able to tell me in a little better detail just what he is. The picture shows the poor thing in a cup from Target as that’s where he was found – outside Target on my way home from a walk.
Signature:  Jennifer Rash

Hi Jennifer,
Though the striped pattern is similar to that of the Colorado Potato Beetle, your beetle is a Ten Lined June Beetle which is a much larger species.