We’re introducing some great new products for spring! This week, we asked our product expert, Craig, about our new grubHALT! Bt for Lawn!
What makes the active ingredient, Bacillus thuringiensis (Bt) galleriae, so effective against grubs? How does it work?
Craig: The patented strain of Bt galleriae that we are using (SDS-502) was developed because of its very specific efficacy against adult beetle pests. The actual toxin in Bt (Cry protein) from each unique strain has specific efficacy against specific insect families. Our grubHALT was formulated to attack white grub (family Scarabaeidae) specifically.
The toxins (Cry protein) are ingested by the grubs once the granules of grubHALT breakdown and percolate through the soil. As the white grubs eat these proteins (while feeding on roots), the protein causes problems with the insects gut which causes a stopping in feeding and eventual death. This is similar to how all Bt’s work.
When is the best time to apply this product for maximum effectiveness?
Craig:The best time to apply is when you actually see the beetles (i.e. Japanese beetle) flying around your lawn. They will lay eggs which will hatch and the young grubs will quickly eat the grubHALT thus killing them.
How does grubHALT! compare to beneficial nematodes?
Craig: It is so much easier to apply (granules vs. live organisms) and is not effected by environmental conditions. For example, nematodes require the soil to be moist prior and after application in order to get the grubs, they should be applied at dusk or very early in the morning, and they are susceptible to extremes in temperature. Another issue with nematodes is that they require moderate conditions for shipment, which are not needed not grubHALT. The cost of grubHALT vs. Nematodes is less expensive. Nematodes have always been a successful product to control grubs organically, but now grubHALT is just easier and has a longer period in which it will work once applied; up to 2 months.