Time to Get Those Grubs!

Appy Grub Control NOW to reduce Billbug and White Grub Populations

Billbugs and white grubs are insects that damage turfgrasses by feeding on the roots. Heavy infestations of billbugs and white grubs may kill grass or attract mammals, such as skunks (!), that damage grass when feeding on grubs.

Billbug grub injury is most common on new lawns, particularly those established with sod. White grubs are the most damaging insects in Colorado lawns, and include masked chafers, May and June beetles, and Japanese beetles. Unlike other white grubs, Japanese beetles are also a terrible pest in their adult stage.

Japanese beetles are fairly new to Colorado and have started to invade areas of Denver as well as Littleton, Centennial and south into Pueblo. They are extremely destructive, non-native, nasty bugs that can quickly decimate ornamental flowers and foliage, and can cause turf dieback. They feast on American linden, apple, apricot, cherry, peach, and plum, birch, crabapple, Japanese maple, Norway maple, pin oak, grapes, tropical hibiscus and canna, beloved roses and many more garden favorites. Adult Japanese beetles emerge from turf areas usually in late June into July.

Which means NOW is the time to treat your lawn to kill the larvae. Apply grub control products, then apply controls again in the summer during the egg-laying period. Look for a product that is labeled for Japanese beetle grubs (larvae). We recommend using a combination of controls — a multi-part attack– to reduce numbers. We carry:

  • Milky Spore: Originally developed by the USDA, Milky Spore is a naturally occurring bacteria Bacillus popillae host-specific to Japanese beetles. In areas treated by Milky Spore, Japanese beetle grub eat the spores during their normal feeding patterns. Then the spores reproduce inside the grub, eventually killing grub within 7-21 days. As the grub decomposes, it releases millions of new spores and these multiply and kill other grubs.
  • Orcon Grub Control Grub Control:  contains Beneficial Nematodes (BN), microscopic organisms that seek out and destroy more than 230 different kinds of soil dwelling and wood boring insects, including Japanese beetle grubs, cutworms, wireworms, weevils, white grubs, fungus gnats larvae, flea larvae, subterranean termites and many more.
  • Bayer Advanced 24 Hour Grub Killer: A “turf rescue formula” that delivers overnight results
    • Contains DYLOX® – kills Grubs in 24 hours
    • Designed to kills billbugs, chinch bugs, crickets, cutworms, earwigs, grasshoppers, Leafhoppers, millipedes, mole crickets, pillbugs, scorpions, sod webworms, sowbugs and ticks
  • Sevin® 2% Lawn Insect Granules
    • Kills over 30 insects including fleas, ants, grubs, scorpions, centipedes, and ticks
    • Use as a perimeter treatment around homes, porches, patios, and decks

 

Read more information on Japanese Beetles from Colorado State University Extension.

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