If you’ve noticed several bare spots on your lawn this season, you could have a problem with grubs.
An anonymous caller suggested The Clarkston News look further into the epidemic, stating many of the older subdivisions in Clarkston have been hit.
‘People should know the problem they’re having is from grubs. If you have a problem in your lawn, it needs to be fertilized. It may be an expensive treatment for $20 a bag, but if you don’t do it, it will be much more expensive to replace a lawn,? the caller said.
Denny Snell, senior manager of the Garden Store at Bordine Nursery in Clarkston said, ‘This is one of the worst years we’ve encountered for a number of years. It’s been really devastating. There are areas that have been totally destroyed.?
He predicted this year would be bad with the dry conditions we had last summer. ‘In the fall, I noticed an up-tick in grub activity.?
Snell, who has been with Bordine Nursery for 19 years, explained it is the European schafer beetle, a pupated grub imported here a few years back, that is the main cause of the destruction.
The adult stage begins in June, he said, when the beetles will mate in the trees at night.
‘The trees will sound like they’re alive. Then the females lay their eggs in the soil, which will hatch in a few weeks.?
Much of the summer the grubs won’t be noticed, but by the fall they are 1/2 inch in size and come to the surface to feed.
‘They’re delectable treats for skunks and moles, so you might also see an increase in varmint activity in the fall.? In the winter they bury back down in the soil and emerge again in the spring.
‘It is important people know the grub has only a one-year life cycle. Understanding this is the key to control.?
If you find five grubs per square foot in your yard, Snell says you have the potential for damage.
‘To treat your lawn, the grubs must be hit at their most susceptible points.? This includes after the beetles have mated and laid eggs in the soil in early July, or when the grubs are born.
‘The product we like best is called Merit, it is 90-plus percent effective. You will be grub free for a year.?
Merit is a growth regulator and can be used over an entire yard. It runs $25 a bag which will cover 5,000 square feet.
‘It’s a cheap fix. It’s safe to use around people and pets, but always follow the directions and don’t abuse it.?
Contact kills include chemicals called Diazinon or Dylox.
‘Diazinon has been the preferred chemical for years, because it is so economical,? Snell said. ‘But it’s been used and abused because it so economical. It’s slowly being taken off the market and will be no longer be produced after the summer. It will be legally sold until Dec. 31, 2004.?
It runs for $10 a bag for 5,000 square feet.
Diazinon works best when grubs are higher to the surface. April and May are best times to apply this treatment, Snell said.
It’s competitor, Dylox, runs $20 or $25 a bag for 5,000 square feet.
A natural alternative to the chemicals is a milky spore. The spore affects the intestinal tract of a grub, killing it.
‘The spore remains in the soil. It is effective for 15 years. It’s an expensive treatment to begin with , but given that it lasts for years, is the less expensive treatment in the long run.?
The milky spore should be applied in three feet grid patterns throughout a lawn.
‘It takes time to work: two full years to fully saturate the soil. You must be patient.?
Snell said it is okay to use an insecticide treatment simultaneously with the milky spore, which is harmless to people and pets.
The spore comes in a powder form which will cover 8,000 square feet of lawn for $90 a can.
Another natural alternative is a parasitic rematode. ‘The disadvantage to this, while very effective, is it is a one shot deal.? It will kill the grub, but will not kill any grubs that appear following the initial eradication. Snell said it is not a long term fix and is the most expensive.
Well-watered lawns tend to resist grubs, he added.