The Japanese Beetle is an invasive species that landed in the US around 1916. It is a voracious pest that does serious damage to orchards and other host plants each summer. My challenge was to develop an an all-natural formula that could repel and kill the Japanese Beetle and protect foliage, even after rain.

Japanese Beetles attacking our apple trees in the summer of 2019.

From 2019 to 2020 I worked to identify and test natural substances on the beetles. I researched and discovered plant oils, essential oils, and amino acids that worked.

Once the ingredients were identified, they needed to work in tandem with carrier oils and result in a stable oil-in-water emulsion. It took a long time to get the right formula. When I finally did, I applied for a patent.

Different formulations being tested.

Successful emulsions were then tested on foliage to determine how well they covered the leaf, if there was any leaf damage, and how long they remained on the leaf – before and after rainfall.

Lab Testing on Japanese Beetles

Lab testing of sprays on foliage.

I conduct continuous lab testing of my formula on live beetles. A control leaf is placed on one side and a test leaf is placed on the opposite side. Live beetles are released in the center of the container, then observed for behavior and consumption of the leaves. In lab testing, TerraBuster’s formula consistently protects the leaf.