| SYMPTOMS | POSSIBLE CAUSES | CONTROLS AND
COMMENTS |
| Yellowing of leaves; and/or no wilting | Nutrient
deficiency - iron or nitrogen | Treat with iron nitrogen
fertilizers |
| | Waterlogged Soil; resulting in poor
nutrient uptake and transport | Improved drainage through
core aerifying |
| Leaves wilted, rolled may have dull, gray
color | Dry soil | Water deeply |
| Grass brown, dry | Winter kill, did not recover in
spring | Use turfgrasses adapted to your area of the
state |
| Grass leaves wilted; white crust on soil | Salt
accumulation on surface, soil moist | Water deeply to
leach salts |
| Grass appears scuffed or bruised, traffic pattern
apparent | Turfgrass wear | Turfgrass
varieties vary regarding tolerance |
| Individual patches 2 to 3", light tan or straw
color | Dollar spot (fungal disease) | Use registered
fungicide |
| Individual patches larger than 3', dark green "halo" or
half moon shaped ring, mushrooms in circular
pattern | Fairy ring (fungal disease) | Not generally
considered harmful |
| Individual circular patches larger than 3', outer edge
yellowish brown, inside area greening | Brown patch (fungal
disease) chronic problem | Use registered fungicide on St
Augustine (except cv 'Floritam') |
| Leaf blades show yellow mottling on St. Augustine
grass | St. Augustine decline (viral disease) | Use
resistant St. Augustine grass varieties |
| Oval-shaped spots, tan or gray colored on leaves and
stems; primarily on St. Augustine | Gray leaf spot (fungal
disease) | Use registered fungicide |
| Small elongated tan spots with dark purple margins,
primarily on Bermudagrass | Helminthosporium leaf (fungal
disease) | Use registered fungicide |
| Gray-white powdery growth on leaves | Powdery
mildew (fungal disease) | Use registered
fungicide |
| Dense, black powdery growth on leaves | Slime mold
(fungal disease) | Control by washing off with water
hose |
| Small patch of cut or chewed grass blades, cobweb-like
growth covers area in early morning | Sod webworm
(insect) | Use registered insecticide |
| Large patches, grass blades white and skeletonized; worms
apparent | Armyworm (insect) | Use registered
insecticide |
| Grass chlorotic and wilted, rapidly turning brown,
usually in hottest spot of lawn; close observation at soil level
shows small, black insect (1/6") with white wings | Chinch
bugs | Use registered insecticide |
| Grass declines - slowly turf thins, very short stunted
stems and leaves on Bermudagrass | Bermudagrass
mite | Use registered miticide |
| Turf thin, lifts from soil as though no roots present;
fleshy, white grubs found in soil | White grub
(insect) | Use registered insecticide; timing
essential |
| Turf uprooted by small tunnels along soil surface; grass
wilted | Mole crickets (insect) | Use registered
insecticide |
| Decline of centipedegrass in sandy soils - may become
thin and even die during hot-dry
weather | Nematodes | No nematicides are currently
for residential lawns. Management program that includes
irrigation when needed can be used to overcome the effect of ring
nematode, but not sting nematode. Bermudagrass or bahiagrass may
be an alternative. Incorporation of organic matter in soil may
help overcome damage; care must be taken to avoid too much
nitrogen for centipedegrass. |
| Circular dead areas that resemble fairy ring
predominantly found in centipedegrass. The spots enlarge each
year and only weeds grow in the spots. | Ground pearls
(scale insects) attack the roots. Pearl-like bodies on the roots
or in the top 2-3" of soil. The pink adult stage that crawls is
present during early summer. | No control known.
Bermudagrass or bahiagrass, appear to be less sensitive and
should be considered for lawns with severe ground pearl
problems. |
| Short, light green to brownish
moss | Moss | Too much shade and/or low soil pH and
low nutrient levels. Get soil test. Removal of excess shade and
application of fertilizer and lime as recommended will help
turfgrass grow. Moss may be an alternative to grasses if the
area has very little traffic and a low maintenance landscape is
desired. |
| Poor quality lawn area around or near trees (during hot
weather) | Shade and tree root competition | Lower
limbs or whole trees may need to be removed.Ground covers and
mulch may be used as well in areas with too much shade for
turfgrasses.Additional fertilization and irrigation may help as
well. |
| Small circular brown spots 1/2 to 1 foot in diameter in
lawn | Animal Urine | Damage is caused by high
soluble salts from the urine. Dark greening around the perimeter
of the spot spot is caused by nitrogen-containing compounds. The
effects can be reduced by irrigating to leach the salts deeper
into the soil |
| Soil compaction ; poor growth of
turfgrasses | Walking, vehicles, playing or
animals | Loosen soil by renovating or coring to relieve
the compaction and improve proper oxygen and water reception for
plants. |
| Centipede decline especially in the
spring | Improper mowing , fertilization, and
irrigation | Excess nitrogen may be part of the problem.
In sandy soils use no more than 1/2 pound of fertilizer per 1000
SF. Mow at one-inch level only. Centipede grass needs no more
than 1 inch of water per week. |
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