Should you spray Japanese Beetles when using Milky Spore

When using Milky Spore to fight a Japanese Beetles infestation should you also spray insecticide? The whole point of Milky Spore is to spread the disease. With time the Milky Spore Disease builds up a defense against this destructive pest. If insecticide is used this reduces the number of Japanese Beetles to infect and help spread the spore. Spraying would seem to be counter productive when using this product.

Unfortunately each year our trees have insecticide applied. The overall effectiveness can be debated. Especially when multiple applications don’t take place. Most of the man made and natural poisons have a very limited time frame for staying effective. This varies from a few days to about one week. So multiple applications are needed.

Most homeowners when seeing the destruction caused by Japanese Beetles will want immediate results. Not wanting to lose plants, lawn or trees do to beetle damage – long term solutions will be discarded. My feeling is this shortsighted approach just leads to an endless loop in the battle to eradicate or diminish the number of Japanese Beetles.

This year the Japanese Beetles in our neighborhood went on the attack in early July. Close to the same time each year. We applied Milky Spore in late Spring. For the past several years we have applied the Milky Spore product in the Fall & again in Spring. There are several ways to identify Japanese Beetle activity. You normally will see them flying around – their behavior could have some people mistaking them for bees. Leaves with holes throughout will litter the area where the activity is taking place. Parts of the lawn that used to have healthy grass will start to show damage.

All these signs are easily seen in our yard right now. Portions of lawn closest to the Japanese Beetle activity looks very damaged. Some of this can be attributed to direct Sun exposure. Although other areas of the lawn with the same exposure don’t look near as rough. The backyard is currently littered with leaves eaten by Japanese Beetles. We have sprayed all trees, flowers and other plants with a natural based grub killer. This product is suppose to have a 7 day effectiveness. When used it should deter Japanese Beetles from eating leaves that have the solution applied. I’m not seeing that result. The grub killer might be effective in killing the larvae but isn’t stopping the feeding process.

Japanese Beetle Traps where used in our yard the first year the infestation was noticed. It was decided that the traps attracted more beetles than they killed. This is a common conclusion you will read online and in newspaper articles. I’ve decided to give the traps another try for two reasons. The first reason is that dead Japanese Beetles give off a scent that is supposed to make an area unattractive to live beetles. My second reason is that I’m going to time the use of traps around the application of Milky Spore.

Late July is when Japanese Beetle females lay their eggs. They also start to feed on roots of plants around this time. In the past we have applied Milky Spore in early to late August. This year we are hoping to apply the product earlier – about a week from now in late July. If timed correctly the Japanese Beetle Traps should attract more pest to be infected with the spore when they tunnel into the ground.

What I find most confusing is none of our surrounding neighbors seem to be experiencing a Japanese Beetle attack. Their yards have trees and plants – some similar to what we have in our backyard. I’m not seeing any evidence of beetle damage on their property. Supposedly Japanese Beetles aren’t to picky about what type of tree or plant they eat. Some websites claim they choose certain plants over others. The majority of beetle destruction has always been concentrated in our backyard. Mainly focused on four trees – three are the same type – the larger tree is a different species.

None of the neighbors who aren’t seeing an infestation apply any type of grub control or other product. Only one of several neighbors uses a lawn company on a regular basis. One neighbor uses a lawn mowing service sporadically. I’m completely confused as to why they aren’t seeing the extreme Japanese Beetle infestation that we have been dealing with for almost three years.

Literature that comes inside a Milky Spore box clearly states you can use insecticide ( natural or man-made poisons ) along with the product and that it will not reduce the effectiveness of the spore disease.

Gabriel Organics Milky Spore Lawn Spreader Mix

Tanglefoot Japanese Beetle Xpando Trap

Safer Brand 70102 Japanese Beetle Trap

Safer Brand 70006 Japanese Beetle Trap Replacement Bait

All my Milky Spore articles show the St. Gabriel Organics Milky Spore product box.

Learn more about Milky Spore and Japanese Beetles in the article below.

Applied Milky Spore last week

Learn the best time to apply Milky Spore to your lawn and garden.

Time to apply Milky Spore to Kill Japanese Beetle Grubs

Using Milky Spore to Kill Japanese Beetle Grubs

Read Milky Spore precautionary statement

No agreement on how to deal with Japanese beetles

“Milky Spore Safely Kills Japanese Beetle Grubs Produced to USDA standards, Milky Spore is the safest material ever developed for control over the larvae (grubs) of Japanese Beetles. Milky Spore is a naturally occurring host specific bacterium (Bacillus popillae-Dutky) that targets and discriminately works to attack the white grubs of Japanese Beetles as they feed on the roots of grass and other vegetation in your yard Milky Spore is not harmful to beneficial insects, birds, bees, pets or man. The product is approved and registered with EPA.”

Milky spore Paenibacillus popilliae Wikipedia

“During the larval stage, the Japanese beetle lives in lawns and other grasslands, where it eats the roots of grasses. During that stage, it is susceptible to a fatal disease called milky spore disease, caused by a bacterium called milky spore, Paenibacillus (formerly Bacillus) popilliae. The USDA developed this biological control and it is commercially available in powder form for application to lawn areas. Standard applications (low density across a broad area) take from one to five years to establish maximal protection against larval survival (depending on climate), expanding through the soil through repeated rounds of infection, in-vers can be used to exclude the beetles; however, this may necessitate hand pollination of flowers.”

Japanese beetle Wikipedia beetle species Popillia japonica

Control of Japanese Beetle Adults and Grubs in Home Lawns

“The bacterial milky diseases, Bacillus popilliae Dutky, has been quite effective at controlling the grubs in certain areas of the eastern United States. The spore count must build up for 2 to 3 years to be very effective and during this time you should not use an insecticide against the grubs that are needed to complete the bacterium cycle.”

Controlling Japanese Beetles – The Homeowner’s Column – University of Illinois Extension

The Beetles of Summer – Japanese Beetles

Kaolin spray – Wikipedia

Japanese Beetles in the Urban Landscape University of Kentucky Entomology

Interesting – don’t recall seeing Milky Spore mentioned as being sold under the Japidemic Doom name previously.

Japanese Beetle Management in Minnesota

Japanese Beetle Colorado State University

Japanese beetle menu expanding; gardeners on edge

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