1. Turfgrass damage
symptoms develop in cold weather, 32-45 degrees F- usually early spring
B.
Turf killed in wettest areas
1. Symptoms follow
water drainage patterns -Water/Ice damage
C.
Circular patches of dead turf ranging from 1 inch to 3 feet
1. Wet grass covered
with white to pink mold, no sclerotia present - Pink
Snow Mold
2. Wet grass covered
with white to gray or bluish mold, minute yellow to brown or reddish
sclerotia present -Grey Snow Mold
2. Turfgrass damage symptoms
develop in cool weather, 45-60 degrees F- usually mid spring and/or
late fall
A.
Irregular patches of affected turf
1.
Powdery mold on leaf surfaces, leaf spots not present
a. Milky white
to gray mold, found mostly in shade and can be wiped off. Turf
becomes thinned -Powdery Mildew
b. Grey to black
streaks in leaves, leaves split into ribbons and curl. Grass
later dies in irregular patches or undergoes a general thinning
-Stripe Smut
c. Pink to reddish
cottony growth on leaves and leaf sheaths, or red thread like
growths extending beyond the leaf tip; may appear tan in patches-
Red Thread/ Pink Patch
2.
Oval, dark-bordered spots present on leaves
a. Leaves with
purplish to brown spots, usually causes thinning and crown rots-
Dipolaris/ Dreschlera Leaf Spot
3.
Irregular blotches in leaves, leaves often die back from tip
a. Yellow to
gray green or brown spots, mostly at or near leaf tips - Septoria
Leaf Spot
b. Purplish to
chocolate brown spots that enlarge and become tan to straw colored-
Ascochyta Leaf Spot
B.
Circular patches or rings of adversely affected turf
1.
Patches 1-6 inches
a. Sunken, straw-colored
patches 1-6 inches, grass leaves matted down -Pythium
Blight
2.
Patches several feet or more in diameter
a. Patches of
dead grass 2-15 feet appear in zoysiagrass as it breaks dormancy
in mid-spring - Zoysia Patch
b. Rings 3 -15
feet or more across, outer ring usually contains darker green
grass -Fairy Ring
3. Turfgrass damage symptoms
develop in warm weather, 60-75 degrees F- usually late spring, early
summer, late summer or early fall
A.
Mostly irregular patterns in turf
1.
Powdery mold on leaf surfaces, leaf spots usually absent
a. Milky white
to gray mold, found mostly in shade and can be wiped off. Turf
becomes thinned - Powdery Mildew
b. Bright yellow,
orange or reddish-brown pustules present -Rust
c. Turf laden
with superficial blue gray, ash gray, creamy yellow or black
powdery structures on leaves, easily wiped off -Slime
Molds
2.
Tan or blighted irregular patches, usually 2-15 inches across
a. Pink to reddish
cottony growth on leaves and sheaths or red threadlike growths
extend beyond leaf tips. May appear in tan patches -Red
Thread/ Pink Patch
3.
Turf is thin and weak
a. Leaves with
purplish to brown spots. Usually causes thinning and crown rots
- Bipolaris/ Dreschlera Leaf Spot
b. Leaves straw
brown. Leaves easily pull loose from crown with a light tug.
Inside of stems hollowed out with powdery frass present -Bluegrass
billbugs
4.
Leaves with blotches or mottling, tips of leaves often die back.
a. Purplish to
chocolate brown spots that enlarge and become tan to straw colored
-Ascochyta Leaf Spot
b. Yellow to
gray green or brown spots -Septoria Leaf
Spot
B.
Mostly circular patterns in turf
1.
Round patches in turf 1-7 inches across. Straw-colored, somewhat
sunken patches.
a. Whitish leaf
spots with brown or reddish brown borders - Dollar
Spot
b. Tan leaf spots
without reddish brown borders -Pythium
Blight
2.
Patches or rings 2-3 feet across, usually with green centers
a. Tan to reddish
brown patches or rings with blackened stem bases and roots -Necrotic
Ring Spot
3.
Rings or arcs 3-15 feet across
a. Outer ring
usually contains darker green grass -Fairy
Ring
4. Turfgrass damage symptoms
develop in hot weather, over 75 degrees F- usually in summer
A.
Irregular patches of thin turf
1.
Irregular, dry patchy turf areas that enlarge and turn yellow to
brown
a. Leaves with
oval or eye-shaped spots, purplish to brown in color, crowns and
roots often rotted and reddish to black -Dipolaris/
Dreschlera Leaf Spot
2.
Leaves brown and thin, usually shriveled and lifeless
a. Roots eaten
or missing, turf pulls back like a piece of carpet when tugged
- White Grubs
b. Turf breaks
off when tugged, crowns and stems hollow - Bluegrass
Billbugs
B.
Powdery mold on leaves
1. Bright yellow,
orange, red or brown pustules - Rust
2. Leaves covered
with slimy or greasy mold, may be bluish gray, creamy yellow or
black powdery, easily wiped off -Slime Mold
C.
Round patterns in turf'
1.
Sunken patches 1-6 inches across
a. Tan leaf spots
without reddish borders. Dead grass matted, slimy, and straw-colored.
Patches may occur in streaks, a cottony growth may be present
on wet turf -Pythium Blight
b. Straw-colored
somewhat sunken patches, tan leaf spots with reddish brown borders
- Dollar Spot
2.
Patches 2-4 feet across
a. Straw-colored
centers often remain green, appear during drought -Summer
Patch/ Necrotic Ring Spot
b. Light brown
grass blades usually not matted, irregular blotches appear on
leaf blades -Brown Patch
3.
Rings or arcs of brown 3-15 feet across
a. Rings or arcs
of brown or stimulated turf 3-15 feet across, mushrooms may appear
suddenly in the ring - Fairy Ring
5. Turfgrass damage symptoms
develop independent of weather conditions
A.
Turf gradually becomes pale green to yellow, grows slowly, often becomes
thinned
1. Interveinal
yellowing of younger leaves, chlorosis of older lower leaves -Iron
Chlorosis
2. Stunting of
growth, older leaves lose green color resulting in a thinner stand
-Nitrogen Deficiency
B.
Turf suddenly appears scorched
1. Usually in patches,
streaks, or bands -Chemical or Mower Burn
2. Bands, streaks
or irregular patterns, grass is stimulated at margins - Fertilizer
Burn
3. Ring of dark
green grass at margins, patches are up to one foot across -Dog
Injury
4. Entire turf
area or patches over slight elevations or mowing corners are yellow
to brown - Scalping Injury
5. Leaf tips are
shredded, appear gray, then tan -Dull Mower
Injury
C.
Regular to irregular patches of dead to dying turf
1.Thatch in excess
of 5/8 inch or construction remnants present -Thick
Thatch or Buried Debris
2. Thinned turf,
presence of tunnels, silken webs and webworms -Sod
Webworms
D.
Turf bare or thinned, often in traffic areas, dense shade, waterlogged
soils
1. Greenish to
brown scum that later forms a black crust - Algae
2. Small green
plants that grow on soil in slight mounds -Moss
3. Soil hard in
heavily trafficked areas, on paths, under swings -Compaction
E.
Turf dry, bluish green, easily tracked, wilts, may later turn brown
-Drought, Wilt or Improper Watering
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