 The adults of the annual white grub are the June bug or June
beetle. If you see (or saw) lots of these adults, that will give
you the possibility of having several grubs. This year we can
throw in the presence of the Japanese beetles and green June
bugs, which came out in late June or July.Grubs usually
infest areas around security lights; along sidewalks, driveways
and patios; and areas with just the right amount of moisture.
Remember that it actually takes 10-12 grubs per square foot to
seriously injure healthy turf.
Prior grub damage or the presence of moles also indicates
that you could have had a large adult crop that could lead to a
large grub crop. Grubs are a favorite food of the mole, and if
you want to keep moles out of your yard, you should treat for
grubs at this time. If you eliminate the food source for the
mole, they will go elsewhere.
Hopefully these points will help you to make your decision.
If you do decide to treat, diazinon and GrubX have been the
major homeowner products. The current list of products includes
imidacloprid and trichlorfon as the chemical active ingredients.
If label directions are followed, these should provide adequate
control of grubs. Figure on application of products from fair
time through early September to allow all the eggs time to
hatch. Japanese beetle larvae will be the last of the group to
hatch, often going as late as mid-August.
Lawn rust
Rust appears as an orange or yellowish-orange powder (spores)
on grass leaf blades, especially in late summer to early fall
when the weather is dry. Rust typically develops on lawns
growing very slowly. Overall, the turf may assume a yellow, red
or brown appearance. Close examination will reveal the pustules,
which easily rub off on your hand. Rust spores can easily be
tracked into homes.
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Low fertility (nitrogen in particular) and low water availability
slow down turf growth, allowing rust to develop. Seasons with excess
rain may have rust outbreaks due to loss of available nitrogen. Cool
nights with heavy dew and frequent light rainfall add to the ideal
conditions for rust to develop. Warm, cloudy, humid weather followed
by hot, sunny weather also favors rust development on lawns.
Kentucky bluegrass, perennial ryegrass and tall fescue are all
affected, depending on cultivars. Rust spreads through air, water,
shoes, equipment and sod. Rust may weaken turf grasses and make them
more susceptible to other problems. Control rust through sound
turf management. Begin by choosing a quality blend of turf grass
seed. Resistance to rust can vary according to the race of the
disease present. Maintain lawns through sound watering, mowing and
fertilizing.
If you are watering, water early in the day so the grass dries
quickly. Also, manage problem thatch. Increase vigor with an early
fall nitrogen application, but don't overdo it. Check soil
phosphorus and potassium levels through soil testing. Also assure
good airflow over the site and light penetration by pruning trees
and shrubs in the area near the lawn.
When rust occurs at this time, improved growth conditions of
early fall often get lawns growing more vigorously and the rust
fades away. Early September is a key time for fertilization. If
conditions are dry, irrigation is also needed to increase the growth
rate of the lawn.
Fungicides are rarely suggested on home lawns for rust control.
Focus on the listed cultural practices described above. The rule of
thumb is that homeowners don't treat lawn diseases. The treatment
must be ongoing if current weather conditions persist. Essentially,
let nature take its course. Then you can reseed with an improved
variety of grass resistant to the disease.
[Text from file received from
John
Fulton, University of Illinois Extension,
Logan County Unit] |
