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Fungi
Q. I have some sort of fungus growing
in small spots in my front garden. I've
never had it before this year. First I thought
some poor animal had vomited and that's
what it was but now I know it's not that
at all. It is like a pale flesh-tone in
appearance and when pouring water on it
seems to not so much foam but almost looks
like it is. How do I get rid of it?
A. You definitely have a fungal problem
going on here. It is severe but controllable
the sooner the better so read this and get
out to your local nursery or garden center
and check their shelves for a treatment.
If you encounter problems ask an employee
for help but read the label before purchasing.
Follow the directions exactly and as often
as called for. Apply in the early morning
hours before the sun is strong and shining
brightly on the lawn areas.
Fungal infestations:
'Melting out' or pink snow mold are two common fungal diseases that cause dead spots in lawns. Now that the weather is drier the fungal diseases are probably inactive
but the dead spots remain. You may overseed or patch with sod but take care that the replacement seed or sod matches the existing turf type.
For future prevention of fungal disease
power-rake to remove thatch and allow the
top portion of the lawn soil to dry between
irrigations.
Hot dry summer weather stresses lawns creating
a perfect environment for fungal diseases.
In our weekend plant diagnostic clinics
lots of turf samples are showing up infected
with dollar spot disease and ascochyta blight.
Identifying Diseases:
The term "dollar spot" refers to silver dollar-sized spots that appear throughout the lawn. With severe infections the spots will coalesce into large dead areas. It's not uncommon on bluegrass lawns for these dead irregular patches to be 10 to 12 feet wide. Although the turf may appear scorched
increased watering may make the disease worse. To identify this disease get down on your hands and knees and look for yellow-green blotches or banding on grass blades. They eventually bleach to white or straw color.
One of the most common lawn diseases on
cool-season turf grass lawns is ascochyta
leaf blight. The height of summer is the
time to be on the look for uniform areas
where the lawn turns straw colored. In many
instances pockets of blight infection may
cause your lawn to develop a patchy appearance.
Check the leaf blades for signs of bleached
areas on the tips. You'll also notice an
abrupt margin between the diseased tissue
and healthy tissue. We've even seen infection
starting at the center of the leaf blade
forming a straw-colored band across the
leaf.
Underlying Causes:
These turf problems usually occur because
of underlying stress. They may result from
poor soil conditions uneven water distribution
soil compaction or using dull mower blades
that create severe wounds for the fungal
spores to enter. Preventive tactics are
best so manage your lawn properly. A healthy
and vigorous-growing lawn can overcome these
fungal diseases on its own eliminating the
need for fungicides.
Prevention and Recovery:
Don't mow the grass too short. Raise your mowing height to 2 to 3 inches tall
never removing more than 1/3rd of the grass blade at any one mowing. Also make sure the mower blades are sharp. Water the lawn to a depth of at least 6 inches as infrequently as possible without creating water stress. In our semiarid climate
water in the very early morning hours or late afternoon to take advantage of higher water pressure and reduced evaporation. During the heat of summer avoid the excessive applications of nitrogen fertilizer. Fast-release
high nitrogen lawn foods will induce tender succulent growth that is susceptible to many lawn diseases. If your lawn needs nutrients
select a slow-release nitrogen formulation that contains iron and sulfur for our alkaline soils. Apply 1/2 to 1 pound of actual nitrogen per 1
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