Dylox results

How is everybody doing with control of grubs using dylox? I'm getting very mixed results, even in the same lawn. I have checked and re-checked my calibration,but the results aren't so great.
I have upped the rate this week because the grubs are larger and hope it stops them. I'm half tempted to take the tree truck out and flood them with sevin! :realmad:

My research came up with this:
Hope it helps

Grub Control Options for Home Lawns
It's time for our annual discussion about lawn grubs. Want to put fear
into the heart of a lawn connoisseur? Just point to a brown patch in
the lawn and yell grubs!

Grubs are the immature stages of some beetles. In our area the highest
populations are annual white grubs. Grubs are whitish, "c" shaped and
wormlike. The adult is the tan 3/4 inch June beetle. Each morning I
find June beetles doing the back stroke in the dog's water bowl (or is
it the dog paddle).

Some lawn areas are more attractive to June bugs laying eggs. More eggs
are deposited at night in warm soil areas such as next to sidewalks
and driveways and often near outside lights. Open areas free of trees
and shrubs are preferred and moist soil is favored over dry soil. This
year egg laying is likely to be concentrated in watered lawns since
most unirrigated lawn areas are dry. The ultimate irony - in most years
highly managed turfs are more likely to get hit with grubs.

Eggs will start hatching the first of August. Damage will usually occur
in August through October. Grubs feed on grass roots until the grass
dries out and dies. The turf can easily be pulled back like a carpet.
Turf can survive some feeding. Less heavily watered turf should be
scouted for grubs in early August. Peel back the grass. Just a couple
grubs per square foot are not a problem to an otherwise healthy lawn.
Ten or more per square foot are necessary to justify treatment.

Home gardeners have some options for grub control: Don't water during
July and August. If the weather is hot and dry, cool season grasses
such as Kentucky bluegrass will go dormant. If a few grubs are detected
, water and fertilize appropriately so turf can recover from some
feeding then reseed or resod areas damaged.

Several pesticides are available for grub control. Diazinon has been
the home gardener's standby for many years. Diazinon is long lasting
and effective, but it can commonly take 3 weeks to kill treated grubs.

Although treated grubs do little feeding, it can be upsetting to still
see live grubs after treatment.

Trichlorfon sold as Dylox is an effective pesticide, but it is short
lived. Grubs need to be present when this insecticide is applied, but
it kills grubs quickly. Dylox is good for rescue situations when damage
is ocurring.

Imidicloprid sold as Merit or Grubex is fairly new to the home gardener
market. It is very long lasting. However imidicloprid takes three
weeks to kill grubs in many situations. Although it is sometimes
marketed for spring application, it should be applied in July once it
is determined that numbers of adults are high enough and that the soil
moisture like this year is low enough to concentrate heavy egg laying
in irrigated turf. In other words, if you see large numbers of beetles
eyeing your lawn and no one else's.

With all home gardener applied products it is recommended that granular
formulations be applied and then irrigated in through the thatch to
the root zone with at least two inches of water. Be sure to read and
follow all label directions.

Parasitic nematodes are showing mixed results. Adequate soil moisture
is critical to their effectiveness and survival.

Spikes O' Death, usually sold as lawn aerator sandals, actually showed
fairly good results in killing lawn grubs in a Colorado State study.
Researchers had to walk the lawn three to five times to achieve an
average of two nail insertions per inch providing entertainment for
the neighbors and aerobic exercise.

The biological insecticides containing milky disease sold as Japdemic,
Doom and Grub Attack, while effective on Japanese beetle grubs, do not
control annual white grubs.

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Dylox has a very short shelf life and humidity will affect the effectiveness. High pH soils will also cause Dylox to lose its effectiveness. If you have limed recently you may find Dylox will not work at all.

Grubs being subterraneous are not always at the same depth. Therefore you may kill the ones near the surface and not those 3 to 4 inches deeper because the Dylox has lost it's effectiveness by the time it leaches that deep. Carbamates are a Little better but doesn't have a great deal more residual.

Now given that your Dylox is good, you might try Soap powder. I know this sounds like Jerry (idiot) Baker. But by applying something like Tide you will bring the Grubs to the surface where the Dylox or Carbamate can get them. Of course the Soap powder must be watered in and give a few days to do it job.

I use dylox often and usually have good results.
Remind customers that it must be watered in properly.
(You can't kill'm if you don't hit'm)
As far as applying at higher rates, doesnt the label carry rates for sod webworm (2lbs per m and 3lbs per m for grubs?)
Those rates should work fine as long as ph is correct, there isn't to much thatch, and the product is properly watered.

Thanks fellas! I guess I'm getting a little squirrely. I forgot about that the grubs will stop feeding but will still be alive. The calls just keep coming and my worst fear is retreating a half million square feet at no charge!

Also keep in mind you need over 10 per sqft to do damage, just because you see one here and there dosnt mean the control is not working.

TSM, IVe heard as little as 1 years old. I just used some up from 2 or 3 years ago, it seems to have worked fine as well.

One problem Im finding is cool nights has gotten some of the bent to go dormant and brown, So the customer panics and thinks grubs, so they dig all over the lawn and find one per 10sqft and call me in a panic.

James Cormier said:

Also keep in mind you need over 10 per sqft to do damage, just because you see one here and there dosnt mean the control is not working.

Click to expand...

James, on average we are seeing 15-20 per square foot.

philk17088 said:

James, on average we are seeing 15-20 per square foot.

Click to expand...

You mean you are seeing that many a week after treatment? James C. meant that you do not need a total kill to prevent further visible damages. If you are seeing 15-20 per ft² to start, it's OK to have 4-5, even 7-8, survive in that ft² after treatment.

The only problem with Dylox is that it penetrates soil readily. If client waters too much, it can be washed right past the grubs without hurting many of them. I tell clients to irrigate 1/2" to activate treatment, then syringe in early afternoon daily (3 to 10 min depending on head type). Too many people think more water will be helpful. Once told a lady to water 1/2 hour, and she watered 3 hours for 3 days straight. Couldn't find a single grub that was even hurt a week later, LOL.