1. Essentials of
Turfgrass
Management
Wilbur D. May Arboretum and
Botanical Garden
May Center at Rancho San Rafael
Bill Carlos. MS. Horticulturist
Washoe County Community Service Department
Regional Parks and Open Space

2. Discussion
 Benefits of Turf
 Turfgass Species
 Irrigation
 Irrigation Audits
 Fertilizing
 Mowing
 Aeration
 Thatching
 Managing Turf Diseases

3. Benefits of Lawn
Right under your feet!
 Increase property value
Reduce dust (12 Million tons/year)
Absorbs heat (global warming)
Cools buildings (8 home lawns
produce 70 tons of AC )
Recreation
Calming effect
Safe playing surface for children
 Provides oxygen (55 sq ft/person/day)

4. Benefits of Lawn
 Curb appeal
 Inexpensive durable ground cover
 Absorbs heat (global warming)
 Provides oxygen (55 sqft/person/day)
 Cost effective for controlling wind and soil
erosion.
 Eliminates dust around homes and
businesses.

5. Benefits of Lawn
 Serves as a fire barrier.
 Safe playing surface for children and pets.
 Reduces A/C cost by 10- to 15 %
 Dense canopy effective in the entrapment
of airborne pollutants.
 Enhances ground water recharge.
 Healthy turfgass absorbs rainfall six times
more effectively than a wheat field and 4
times more than a hay field (Beard 1992).

6. Lawns
 Lawn consist of a population of individual
grass plants.
 Important to select the correct variety for the
situation.
 Remember, “The grass you sow/grow will be
the lawn you mow”.
 Need to consider species and climate before
planting.

7. Trufgrass Species
 90% of Northern Nevadan‟s are Bluegrass
 Parks and some ballfields are Tall Fescue

8. Cool Season
Grasses
Northern Nevada
Southern Nevada

9. Grasses for Northern Nevada
 Kentucky Bluegrass
 Fine Fescue
 Tall fescue
 Perennial Rye
 Bent
 Buffalo grass (cool warm season grass)
 Turtle Turf (Koeleria macrantha)

10. Kentucky Bluegrass
Characteristics (Poa pratensis)
 Rhizomes
 Boat shaped
tip.
 Deep green
blue color.

11. Kentucky Bluegrass
(Poa pratensis)
 Good color easy to grow.
 Not shade tolerant.
 Will burn if mowed to close and go
dormant if not irrigated correctly.

12. Kentucky Bluegrass
(Poa pratensis)
 Seeding rate 3 to 6 lbs. Per 1000 sq.ft.
 Mowing height 2-3 inches.
 More susceptible to diseases
 Shallow root system (4-8 inches deep)

13. Kentucky Bluegrass Varieties
Less expensive
Group I 
 „Park‟ – Rapid
 „Kentucky Blue‟ growth.
 „Park‟  „Merion‟ – Heavy N
 „Merion‟ feeder.
 „Newport‟  „Newport‟ – Course
seed stalk and poor
drought tolerance.
 All are susceptible to
diseases compared
to new varieties.

14. Kentucky Bluegrass Varieties
Group II  All are low spreading
 „Fylking‟  Fylking used for high
or low maintenance.
 „Baron‟
Powdery mildew.
 „Syndsport‟
 Baron fast grower.
 „Pennstar‟
 A-34 shade tolerant.
 „A-20‟ Fe chlorosis.
 „A-34‟  Nugget – Shade
 „Nugget‟
 „Sodco‟

15. Kentucky Bluegrass Varieties
Group III  All low spreading
 Best performers
 „Parade‟
 Good wear
 „Ram I‟
 „Parade‟ good wear.
 „Touchdown‟
 „Glade‟ shade
 „Glade‟
tolerant
 „Majestic‟
 „Majestic‟ good color
 „Adelphi‟ with poor
maintenance.

16. Kentucky Bluegrass Varieties
USDA Turfgrass Foundation
 Bedazzled  Moon Shadow
 Midnight II  Rugby
 Impact  Nuglade
 Total Eclipse  Chicago II
 Award  Quantum Leap
 Arcadia  J-1513
 J-1838  Alpine
 Brilliant  Moonlight

17. Local Blend of Kentucky Blue
 Western Turf ™
 24% Rugby
 24.9% Ascot II
 24% Limousine
 24% Quantum Leap

18. Sample of a Mixture
Low Grow Mixture
45% Hard Fescue
Warwick
25% Kentucky bluegrass
Arlene
25% Perennial Ryegrass
Elite
5% Annual Ryegrass

19. Mixture of Grasses
Hardy Morningside Playground
35% Creeping Red Fescue, Boreal
30% Crested Wheatgrass, Turf Type
30% Kentucky Bluegrass, 5-Star
5% Annual Ryegrass
A hardy, drought tolerant, traffic resistant blend specifically
suited for areas where frequent watering is a problem. Maintains
green color for up to 6 weeks without water.

20. Mixtures
Deluxe Velvet Green
55% Kentucky Bluegrass, 5-Star
Brand
40% Creeping Red Fescue,
Boreal
5% Annual Ryegrass

21. Irrigation
 Most challenging for
managers and
homeowners.
 Fifty to seventy percent of
our summer water supply
is used for outdoor
irrigation.
 First sign of drought stress
is “foot-printing” caused by
the lack of turgidity in the
grass.

22. Irrigation
 Begin the season with a visual audit.
Activate the system and check for:
 Leaks, wiper seals.
 Broken and buried heads.
 Nozzles out of adjustment or wrong
nozzles, pump capacity.
 Mixed heads/mixed precipitation rates
 Blocked spray patterns by tall grass.

23. Irrigation
 Signs of drought stress: blue-green or
gray leaf color. If left unwatched, the
size of the areas will increase (confused
with patch diseases). Leaf symptoms
include rolled,drooping or folding
leaves. Occurs when temperatures
begin to rise.
 If unirrigated, turf will go dormant.
Water will be stored in roots and
crowns long after the shoots die.

24. Drought Stress on Turf
 Irrigation
was shut off
during
construction

25. Drought Stress on Turf
 Turgor is lost due
to the lack of
water.
 When water is
applied, the brown
grass will continue
to die and mimic a
turf disease.

26. Advanced Irrigation Audit
 Perform a “catch can test.”
 This will assist in determining the
uniformity and distribution of the system.
 Frequency and time will be determine by
climatic conditions.

27. Irrigation Audit
 Place
cans at a
head and between.
 Run sprinklers.
 Record time.
 Measure water in
each container.

28. Irrigation Scheduling
 For scheduling go to, www.washoeet.dri.edu
and click on “Water Like the Pro‟s”.
 Advance scheduling “click-on” the weather
stations. (rule of thumb – irrigate to a depth of 6
inches)
 Best time to water is early in the morning when
the wind is down. There is no conclusive
evidence watering at night causes lawn disease,
but why take a chance?
 Golf courses and parks, water when you can!!!

29. Washoe ET

30. Weather Station Sites

31. Water Like the Pros
Use Et Rates
www.washoeet.dri.edu

32. Water Like the Pro‟s
 This web site will give you the approximate run
times based on GMP‟s and sprinkler head
operating pressure.
 Assist with scheduling.
 Rancho San Rafael Park
 Pumps undersized
 Too many valves on one station resulting
inefficiencies and poor turf quality (donuts in turf).

33. Water Like the Pro‟s

34. On-Line Calculator
 Calculate your runtime
 Water Pressure ____ psi
 Delivery Rate ____ gpm
 Sprinkler Spacing ____ feet
 Spray Radius ____ feet
 Et inches ____ per day
 Irrigation Efficiency ____ percent
 Calculate Runtime result minutes per day

35. Fertilizer Timing and Rates

36. Fertilizer Applicators
Commercial broadcast
spreader
Tractor spreader
Hand broadcast spreader

37. Fertilizer Calibration
 Stop and check to make certain the spreader is
calibrated for the correct amount of N you want
to apply.
 One pound of actual nitrogen per 1000 sq ft is
recommended for one application, but can vary.
 Rancho, 21 acres. Need 80, fifty pounds bag of
fertilizer to get 1 pound of actual per 1000 sq ft.
2 tons per application.
 Need 3 to 4 application per year or 6-8 tons per
year.
 Amount depends on guaranteed analysis,
numbers on the bag, i.e., 21-9-15.

38. Fertilizer Calculation
 Recommend one lb of N per application
per 1000 sq ft of turf.
 Take 1 lb and divided it by the first
number on the bag which is Nitrogen.
 Example 20-0-0 (20% is nitrogen).
 1/.20 = 5lbs. (the rest is a carrier)
 Need 5lbs of 20-0-0 to apply 1lb of AN per
1000 sq ft.

39. Fertilizer Application Rates
 Very low Maintenance - one application per
year or one pound of actual nitrogen per year.
 Minimum maintenance – two application per
year or two pounds of actual nitrogen per year.
 Moderate to high maintenance – three to six
application per year. Golf courses frequently
apply more to greens sometimes weekly for
appearance.
 High frequency golf courses - 8-10
application for greens. Don’t forget iron!

40. Effects Fertilizer

41. Fertilizer Timing and Rates
 First application, mid March to mid -
April. Use ½ to one lb. of N per 1000
sq.ft. of lawn. Use Fertilizer with Fe.
 Second application - apply May to
Mid June at the one pound rate.
 Snack - in July/Aug ½ of N. per 1000
sq.ft.if needed but not always
recommended. Golf courses fertilize on
a as needed basis.

42. Fertilizer Timing and Rates
 Third application – Mid Aug – mid Sept.
one pound rate.
 Last application is late October or
around the first of November. Apply one
pound of N using fast release nitrogen.

43. Available Organic Fertilizers
 Nature's Intent Lawn Fertilizer
 (9-3-4) Apply 10 lbs for 1000 sqft.
 Any organic fertilizer will work. Benefits
include maintaining healthy soil and avoid
burning the lawn.

44. Mowing Heights
“The Grass You Grow Will
Be the Lawn You Mow”
Species Inches
 Bentgrass ………….. 0.25 -
0.75
 Ryegrass …………… 2.0- 3.0
 Kentucky bluegrass …. 1.5 - 3.0
 Tall Fescue …………….. 2.0 - 4.0
 Fine-leaf fescue………. 2.0 - 2.5

45. Mowing Lawns
 Safety first
 Remove debris
from the lawn
 Wear ear
protection
 Gloves and work
boots.
Don‟t try this at home or work.

46. Mowing and Effects
 Close mowing removes leaves and
carbohydrate production.
 Increases shoot production but reduce
roots.
 Lower cuts will produce shallow roots.
 Weakens the turf ability to recover from
environmental stresses (droughts).

47. Effects of Close Mowing
 Lower cuts increase the incident of
disease. Occurs as a result of less
stored food and shallow roots.
 Scalping will cause the root and shoot
to stop growing. Depending on the
health of the lawn, effects may last
several day to weeks.

48. Mowing vs. Rooting Depth.
Impact on
root
development.

49. Results Mowing Close
The lawn on the right is consistently mowed shorter than the lawn on
the left. Both lawns were irrigated nearly the same. By September the
shorter lawn is drought stressed thus turning brown. Even after
applying more water, weeds started to grow first before the grass.

50. Effects of Close Mowing
 Repeated scalping will cause the lawn to
eventually thin and die.
 Follow the 1/3 rule:
 Remove only 1/3 of the grass blade at
on time.
 If lowering the blades are required, do it
gradually over time.

51. Edging Lawns
 Do not bevel edge
with a string
trimmer.
 Bevel edging
allows weeds to
invade.
 Prone to drought
Stick edging - Best appearance
 Prone to insects, Looks Manicured
Healthier for lawn
bill bugs.

52. Mowing Pattern
 Mowing pattern as critical as mowing
heights.
 IF you can, alternate direction each time
you mow. This will reduce the chances of
compaction and ruts in the lawn.

53. Week 1
Alternate Week 2
Mowing Week 3
Patterns
Week 4

54. Mowers: Reel vs. Rotary
 Reel Mowers: Consist of 5 to 11 blades.
Blades are pushed against the bedknife of
the mowers which cut the leaves like
scissors. Cleanest of cuts. Used on golf
courses and large turf areas.
 Greens mower, capable of cutting blades
to a height of 0.125 inches.

55. Examples of Reel Mowers

56. Energy Efficienct
Modified Reel Mower

57. Rotary Mowers
 Blade rotates horizontally at
high speeds. Blades cut by
impact and speed (leaves
are severed).
 Depending on the sharpness
of the blades, tips can revel
a shredded appearance. The
duller the bladed the
greater the damage.

58. Rotary Mowers
 Torn shredded tips are more prone to
diseases.
 Rotary mowers blades need to be sharpen
after 20 hours of use, for some that may
mean changing blades twice per week.
 Should not be used at heights less than 1
inch, scalping will occur.

59. Make mowing your hobby!
Rotary mower blade deck.

60. Clipping Removal
 There is no evidence that returning
clipping to the lawn causes thatch.
 Evidence show when clippings are
returned they provide nutrients in the
form of nitrogen.
 It has also been estimated 100 to 150
lbs of nitrogen is eliminated per acre
when clipping are collected for an entire
season.

61. Aeration and Dethatching
 Aeration - Spring and fall
maintenance.
 Aeration relives compaction
 Increase water infiltration
 Provides oxygen to the roots

62. Aeration and Dethatching
Aerating
 Increase fertilizer
response.
 Release toxic gases
that could buildup
as a result of poor
water percolation.
 Golf courses aerate
as needed, aerate
and top dress.

63. Core Aerating
Equipment

64. Core Aerating
• Okay to leave the
plugs, but not on
golf greens.
• Serves as top
dressing.
• Plugs break down
after several
irrigations.

65. De-thatching (Vertical Mowing)
 Removal of dead blades found near the
surface of the lawn.
 De-thatch when you have 30 days of
favorable growing conditions.
 Late summer is ideal time when
temperatures are cool and there is rapid
root development.
 Detaching decreases concentration of
plant pathogens over-wintering in dead
grass blades.

66. Thatch & De-thatching
 Thatch or the mat is found above the soil
line. Spongy organic material.
 Caused by over fertilizing.
 Over watering.
 Soil compaction.
 Begin management when thatch layer is
½ or greater.

67. Thatch and Mat Layer
THATCH LAYER
MAT LAYER

68. Problems
 Thatch or mat, shed water, preventing
water infiltration.
 Minimize movement of water and fertilizer.
 Turf becomes susceptible to diseases.
 Provides conditions for insects such as cut
worms, sod web worms and bluegrass
weevils.

69. De-thatching
 After thatching, shoot density
increases (Beard 1973).
 Turf will recover if water and fertilizer
are applied.
 All material lifted must be raked and
removed.

70. Dethatching
 Severity of dethatching is altered by
the spacing of the tines and height of
the vertical mower.
 With lighter vertical mowing
equipment, several passes may have
to occur in different directions to
remove an significant portion of
thatch.

71. De-thatching Equipment

72. WEED CONTROLL

73. Weed Control
 ID weed first.
 Purchase proper
pesticide.
 Apply it at the right
time of year.
 Apply it at the right
stage of development.
 A weed is plant
where it is not
wanted.

74. Weed Control
 Apply a pre-emergent herbicides in spring
to kill geminating weed seedling. Apply
Mid Feb - March and or early April.
 Broad leaf weed control (post
emergence): Apply after weeds have
emerged. Common broad weed control,
2,4-D. Watch for drift. Can‟t spray with 10
mph winds.

75. Weed Control
 Know the difference between a monocot
weed and dicot weed (grasses) before you
purchase or apply a pesticide.
 READ THE LABEL and follow it to its
entirety.

76. Monocot vs. Dicot Weeds

77. Monocot VS Dicot Weeds
 Monocots
(“Mono”
meaning one)
 One cotyledon
 Parallel veins,
grass weeds.
 Different control
vs dicot weeds

78. Monocot VS Dicot Weeds
 Dicots (“Di”
meaning two)
 Two cotyledons
 Netted veins

79. Beware of Weed and Feed

80. Common Turf Weeds
Dandelion Knotweed
Red Stem Filere Puslane
Annual Bluegrass Blackmedic
Niblewill Tall Fescue
Clover Saltgrass
Spotted spurge
Buckthorn or Plantain

81. Turf Weeds
• How do weeds spread?
Wind, water and human
movement.
Combating Turf Weeds:
• Pre-Emergent Herbicide
When? Early Spring and
fall. Spot treat throughout
the season. Weeds will
always be present. Where
this is water there are
weeds!
2/22/2013 81

82. Broad Leaf Weed Id
• Netted veins

83. Narrow Leaf Weeds
 Weed Grasses
 Require different
herbicide than
board leaf weeds.

84. Dandeloin

85. Red Stem Filere

86. Cheese Weed, Little Mallow

87. Annual Bluegrass (grass weed)

88. White Clover

89. Creeping or Spotted Spurge

90. Buckhorn
Plantain

91. Knot weed

92. Common Purslane

93. Black Medic

94. Nimblewill (grass weed)

95. Alta tall fescue
in bluegrass lawn.
Often confused
with crabgrass.

96. Salt Grass
 Mature Salt
Grass

97. Common Cool Season Turf
Diseases
 Fairy Ring
 Melting out
 Dollar Spot
 Necrotic Ring
Spot
 Brown Patch
 Snow mold
 Antracnose

98. Disease Triangle

99. Fairy Ring

100. Fairy Ring
Prefers dry
under-watered
and thatchy
turf.

101. Fairy Ring
• There are over 50 - 60 species
of the ring fungi identified.
• Most common s the genus and
species Marasmius oeades.
• While the rings can develop in
well-maintained lawns, they are
often found in lawns that are
under - watered and under -
fertilized.

102. Fairy Ring
• The fungal rings begin at a central
point and grow outward at a rate of 1
foot to 2 feet per year.
• Often rings will grow right out of a
small lawn.
• Fairy ring survives in the organic
debris in the soil or in the thatch
layer, the area of dead roots and
shoots found just above the soil line.
• Damage can be seen in turf as a band
of unsightly large arcs or circles of
dead grass.

103. Fairy Ring
• It is not known if
fairy ring spreads
by white, hair-like
fungal masses
known as fungal
mycelium, and/or by
spores produced by
mushrooms. White Fungal Mycelium

104. Three Types of Fairy Ring
Type I Type II
Most devastating.
Present in under-watered and
Soil becomes water repellent.
Appear during hot dry summer or under fertilized turf.
drought conditions.

105. Fairy Ring
Type III Most Common
Type II and III are occur during wet
cool spring.

106. Fairy Ring
• Difficult to control
with chemicals.
• Removing requires
removing the soil &
replacing with clean new
topsoil. Re-sod or reseed
afterwards.
• Aerate or mask Type II &
III and irrigate. This
interrupts the hyphae and
hydrophobic conditions.
Water deep (2ft) weekly
for several weeks.

107. Fairy Ring
Common type
Found in landscapes.
Rake or pick
mushrooms if there
are children or pets.
In some cases they
can be mowed up.

108. Controls
Limited success treating
fairy ring with chemical
fungicides and wetting
agents (chemicals used to
break the surface tension
of the soil and allow for
water adsorption).
Due to inconsistent soil Fairy ring on golf green.
textures and compacted Soils are deep and uniform.
soils.
Golf Courses seem to have
better results on greens.

109.  The fungicide (Flutolanil for
residential sites and
Azoxystrobin for
commercial sites) cannot
penetrate the soil deep
enough to completely kill the
fungi. The rings may be
suppressed by drenching the
infected soil with a
fungicide. However,
symptoms may reappear
when treatments are
discontinued.

110.  Drilling
 Drenching, Injecting and Aerifying
 Soil Mixing and Tilling
 Chemicals:
 Torque
 Bayleton
 Armada
 Tarton
 Honor
 Tourney
 Banner etc.

111. Additional Information
 Fairy Rings In Lawns, University of Nevada
Cooperative Extension Fact Sheet 03-20.
 UC Davis Cooperative Extension, IPM Program
 Utah State Cooperative Extension
 Colorado State Cooperative Extension

112. Melting Out
 Drechslera poae.
 Cool season, 64°F
to 85°F or 50°F
to 75°F degrees.
 Turf begins to
fade our or “melt
out”.
 Disease always
present in the
soil.

113. Melting Out
 Stays dormant in
plant tissue, fungal
thread.
 A saprophytes and
can infect lower
roots.
 Most devastating to
warm season Conidia of Drechslera
grasses.

114. Melting Out Controls
 Reduce shade
 Improve soil aeration and water
drainage, and control thatch.
 Avoid dry spots and maintain as high a
cutting height as feasible.

115. Melting Out Controls
 Apply recommended rates of nitrogen
fertilizers.
 Select resistant cultivars.
 Fungicides should not be necessary in
most situations. For susceptible
cultivars, treat at the onset of
symptoms.

116. Dollar Spot
 Sclerotinai homeocarpa
 Show up at 59 to 86
degrees.

117. Dollar Spot
 Dollar spot often is confused
with Ascochyta leaf blight. A
major problem in Colorado.
 Turfgrass under stress is more
susceptible to infection.
 Proper lawn management, such
as aeration, proper watering
and fertilization, will reduce
dollar spot problems.

118. Dollar Spot Controls
 Major concern on bent grasses (golf
greens)
 On Kentucky bluegrass lawns the fungi
may infect large areas in just a few
days. Infected areas 4 inches or larger
may run together, causing large patches.
Irregular patches to 12 feet wide are
not uncommon on bluegrass lawns.

119. Dollar Spot Controls
 Use fungicides only in situations with
recurrent dollar spot problems.
 Ensure nitrogen levels are sufficient to
sustain a moderate rate of shoot
growth.

120. Necrotic Ring
Spot
 Ophiosphaerella
korrae
 Resemble small
fairy rings. University of Nevada
Cooperative Extension
Active at 68 and
86 degrees.

121.  Appears two to three
years after lawn
establishment, however
may not develop in a
lawn for a decade or
more.
 Intensifies in late July Colorado State University
Cooperative Extension
or August during
periods of summer
stress.

122.  Advance state
of necrotic ring
spot.
 Can occur in a
localized area.

123.  Prepare site before sodding or
seeding.
 Resistance.
 Overseed diseased patches with
perennial rye.

124.  Do not overwater.
 Follow good management practices on
established lawns.
 Maintain the turf at a height of 2 ½
to 3 inches. Remove no more than
1/3rd of the blade at any one
mowing.

125.  Avoid applying excessive amounts of
nitrogen fertilizer.
 Apply 4 lbs total nitrogen per 1000
square feet per year over fertilization
may enhance NRS.

126.  Sulfur amendments can reduce NRS
severity. The exact mechanism by
which this occurs is still unclear,
although it is thought that sulfur
acidifies the soil surrounding the
roots and inhibits the spread.

127.  Several fungicides are labeled for the
control of NRS but their
effectiveness has been inconsistent,
i.e. Heritage, Headway, Chipco
Tourney, Eagle, Banner etc.
 Make an application in May when soil
temperatures reach 65° F at a depth
of 2 inches. This usually occurs in
mid-May or later.

128. Brown Patch
 Mid-Summer
disease.
 Requires free water
and high
temperatures.
 Mimics drought
response.
 Spreads quickly.

129.  Occurs at between
75°F to 95°F, with the
optimal conditions for
leaf colonization being
temperatures of 85°
to 90°F with high
humidity or extended
leaf wetness periods.
 Prefers closely mowed
turf!

130. Brown Patch
 Affects bentgrasses,
fescues, ryegrasses,
& bluegrasses>
 On closely mowed
turf, patches of
blighted turf will
often have a purplish
edge or smoke ring
appearance in the
early morning hours.

131. Brown Patch Control
 Irrigation is an
important part of
controlling Rhizoctonia
diseases.
 Fungicide applications
can be necessary if leaf
wetness and soil
moisture cannot be
managed (for instance,
as a result of rain or
high humidity).

132. Brown Patch Control
 Combine cultural management
techniques with fungicide
applications for the best
management of the disease.
 Improve water and fertility
management are useful in
preventing the development of
rhizoctonia blight.

133. Brown Patch Control
 Reduce shading and
improve soil aeration
and water drainage.
 Irrigate in the pre-
dawn or early morning
hours to promote leaf
drying.

134. Brown Patch Control
 Irrigate only when
needed to a depth of 4 to
6 inches.
 Remove dew from leaves
by polling or light
irrigation. Avoid over
nitrogen fertilization that
results in a soft foliage
growth.
 Maintain thatch at less
than 0.5 inches.

135. Seedling Blight
 Pythium spp.
 Water mold fungus.
 Prefers free moisture and high
temperatures.
 Occurs on newly plated lawns in
summer and low lying areas

136.  Hot, humid weather alert for
Pythium blight outbreaks.
 Need 12 to 14 hours of wet
humid conditions for several
consecutive nights.
 Initial symptoms; circular
patches of collapsed, water-
soaked leaves and stems on
close-mown turf.
 Observed early in the morning.

137.  May see cottony white
mycelium.
 Infected turf dies and
becomes matted.
 Large areas of turf may
be killed within a matter
of days.

138. Cool-season turfgrasses should not be

fertilized with more than 0.25 lb N per
2
1000 ft when conditions favor Pythium
blight activity. Avoid establishing turf
in low-lying areas that will collect water.
If necessary, install subsurface
drainage to prevent wet soil conditions.

139. Relieve compaction and maintain soil drainage

aerification, and topdress golf course putting
greens regularly to minimize thatch
accumulations.
Do not mow or irrigate when Pythium

mycelium is present on the foliage to minimize
spread of the pathogen. Collect and promptly
dispose of clippings from infected areas and
ensure that mowing equipment is washed
before going to an uninfected area.

140.  Due to the potential for rapid development
of this disease, high value areas and
susceptible grasses should be protected
with a preventive fungicide program.
Applications should be initiated when
night temperatures consistently exceed
65°F and repeated on 14 to 21 day
intervals as directed on the fungicide
label.

141. Anthracnose
Colletotrichum cereale
 Seen on golf
greens.
 Susceptable host
are annual
bluegrass or
creeping bent Anthracnose acervuli
varieties.
 May-September
in certain areas.

142. Causes
Close mowing,

Drought stress

Low fertility

Excessive traffic

Poor soil drainage

Excessive

thatch/organic
matter
accumulations.

143. Controls
 Cultural
 Control annual bluegrass.
 Rise mowing heights during
periods when the disease is
most active.
 Fertilizer at the
appropriate amount.

144. Controls
Cultural
 Regularly aerify
 Top dress after aerification
 Fungicides should be your last resort.
 Used only a preventative not curative.

145. Identification of Plant
Diseases
Local Cooperative Extension Office
State of Nevada Division of
Agriculture.
Shouhua Wang, Ph.d. Plant Pathologist
Office: 775-353-3765
Lab: 775-353-3771
Fax: 775-353-3657
Email: shwang@agri.nv.gov

146. Turfgrass Management
Summary
 Mow High
 Don‟t remove any more that 1/3 of the
leave blade.
 Fertilize 3 to 4 time per year
 Check the irrigation frequently.
 Most brown spot will occur in summer due
to the irrigation system.

147. Turfgrass Management
Summary
 If disease are suspect, have it identified
first, Cooperative Extension of Nevada
Division of Agriculture.
 Always ID weeds first before applying a
herbicide.
 Good management will reduce disease
and weeds.

148. Essentials of Turfgrass
Management
Wilbur D. May Arboretum and
Botanical Garden
www.washoecountyparks.us
www.maycenter.com
785-4153
Bill Carlos. MS. Horticulturist
Washoe County Community Services Department
Regional arks and Open Space