How to Get Rid of Lawn Grubs with Natural Home Remedies
If your lawn is dying with signs of brown and dried grass then the problem could be grubs. Beetle grubs – especially the larvae of Japanese beetles and their relatives in the Scarab family – feed on the roots of grasses and other plants. They are mostly underground so difficult to identify. Here are our top suggestions for getting rid of the grubs with natural home remedies.
1. Apply Beneficial Nematodes to the Soil
One of the best ways to eliminate grubs specifically – without harming beneficial insects – is to introduce beneficial nematodes into the soil. Nematodes are microscopic roundworms, one of the most abundant animals on Earth. There are three common species, one of which is a nematode called Heterorhabditis bacteriophora. This species has an endosymbiotic relationship with genus of bacteria called Phothorabdus. They live in the nematode’s digestive tract. The nematode pierces the outer skin of a beetle grub, and releases the bacteria into its body. These bacteria release toxins that cause fatal problems like apoptosis (cell death) of blood cells.
Within forty eight hours, the grub will die. The Photorhabdus bacteria then feed on the body of the dead grub, the process of which enables the nematode to also obtain nutrients from it. Along with grubs, the nematode and its endosymbionts will also attack some other pest species, notably the larvae of cabbage white butterflies and tobacco hornworms.
2. Use Milky Spore Control
Milk spore products contains a bacteria called Paenobacillus popilliae (formerly known as Bacillus popilliae), which targets grubs — especially those of the Japanese beetle. The bacteria spores can be introduced to your soil with a simple one-time application, at a time of year when the grubs are most vulnerable to them. (Usually August.)
The grubs ingest the spores, which cause the “milky spore” disease, which kills them by interfering with normal blood circulation. The bacterial spores act as an effective population suppressant, becoming concentrated in the areas with the highest numbers of grubs. They’ll also persist in the soil for an average of two to ten years, helping to prevent a resurgence in the grub population. As a bonus, birds and other insect predators will often relocate the grubs to eat them, helping to further spread the spores to nearby areas.