Diseases ›

Dollar Spot

Symptoms

On putting green turf, dollar spot appears as small spots, approximately the size of a dollar coin, that are bleached-white or light tan in color. On turf mowed at heights greater than 0.5”, the spots may expand in size up to 6” or more in diameter. The affected leaves typically remain upright and are characterized by having white or light-tan lesions with light reddish-brown margins. As the lesions expand, the leaves are girdled and the upper part of the leaves dies slowly. Distinct lesions are sometimes not evident on close-cut turfgrasses; instead, the leaves die back from the tip and turn white or light tan in color. The grass in the spots may be killed to the soil surface if the disease continues to develop, and many spots may merge to produce large blighted areas. Short, fuzzy white mycelium is often observed on affected turf in the morning when dew is present.

Development Factors

The dollar spot fungus begins to grow and infect susceptible grasses in the spring when night temperatures exceed 50°F, even though symptoms of the disease may not appear until later in the spring or early summer. In addition, the pathogen requires extended periods of leaf wetness, 10 to 12 continuous hours. Heavy dews that often form during cool nights in the late spring or early summer are most conducive to the disease. Extended periods of wet, overcast weather can also lead to severe dollar spot epidemics on susceptible grasses. Dollar spot remains active throughout the summer in many areas, but disease activity typically slows when high temperatures consistently exceed 90°F.

Turfgrasses that are deficient in nutrients, especially nitrogen, are more prone to dollar spot and also recover from the damage more slowly than well-fertilized turf. The disease is also encouraged by drought stress, low mowing, excessive thatch accumulation, frequent irrigation, and low air movement. Certain cultivars of creeping bentgrass, perennial ryegrass, and Kentucky bluegrass are very susceptible to dollar spot, while others are fairly tolerant.

Cultural Control

Use of resistant cultivars is one of the most effective means of dollar spot management. This is particularly important for creeping bentgrass, perennial ryegrass, and Kentucky bluegrass, as cultivars vary widely in their susceptibility to the disease. Base turfgrass selection on University recommendations or regional cultivar trials operated by the National Turfgrass Evaluation Program or local universities. When planting cool-season grasses, use blends and mixtures of multiple species and varieties whenever possible..

Adequate nitrogen fertilization will help to prevent dollar spot, and will also encourage plants to recover quickly from the disease if it occurs. Select nitrogen sources, rates, and timings based on local University recommendations for your turfgrass species and climate. In general, golf course putting greens established with creeping bentgrass or annual bluegrass should be fertilized with 0.5 lb N/1000 ft2 per growing month. More or less nitrogen may be required for your location depending on soil type, rainfall amounts, traffic intensity, and other management practices. Deficiencies in other nutrients that limit foliar growth may also exacerbate dollar spot problems. Use soil test results to apply the recommended amounts of phosphorus, potassium, lime, and micronutrients.

Dollar spot is encouraged by drought stress and leaf wetness. Proper irrigation timing is needed to balance these factors. Irrigate based on the moisture status of the soil, not on a calendar schedule. Use the Turf Irrigation Management System available on TurfFiles to schedule irrigation based on weather conditions and turf needs. When irrigation is necessary, it should be applied early in the morning, between midnight and 6 AM, to keep leaf wetness periods as short as possible. Mowing, dragging, or whipping the turf in the morning to remove dew can help to prevent dollar spot, but these practices can spread the disease if it is actively developing. Improve air movement and reduce humidity by pruning trees, clearing unwanted vegetation, or relocating desirable plants.

Excessive thatch accumulations greatly encourage dollar spot activity. Remove excess thatch by vertical mowing or power raking. Golf course putting greens should be aerified regularly and topdressed with sand to reduce thatch buildup.

Dollar spot is readily spread in leaf tissue or clippings from infected areas. Avoid spreading the disease by washing equipment before entering an uninfected area, by encouraging golfers to clean their shoes between rounds, and by removing and disposing of clippings taken from infected areas.

Chemical Control

Many fungicides control dollar spot, but preventative applications are most effective. A preventative program should be implemented in the early spring when night temperatures consistently exceed 50°F. When applied on a curative basis, fungicides must be applied at high rates and short application intervals.

Uniform spray coverage is important for maximizing fungicide performance; even small gaps in coverage may allow dollar spot to develop. Nozzle type, nozzle pressure, and dilution rate have the greatest impact on the uniformity of fungicide applications. Nozzles that produce coarse to extremely coarse droplets, such as TurfJet or Raindrop nozzles, dramatically reduce the performance of fungicides for dollar spot control. Air-induction or flat fan nozzles that produce fine to medium droplets are recommended. In order to provide thorough coverage of the turfgrass foliage, fungicides should be applied in 2 gallons of water per 1000 ft2; lower carrier volumes reduce the performance of fungicides for foliar disease control.

The fungus that causes dollar spot develops resistance to fungicides very quickly. To prevent or delay the onset of fungicide resistance, use integrated management to minimize fungicide use, rotate among fungicide classes after each application, and tank-mix systemic fungicides with a contact fungicide.

Fungicide and Formulation1
Amount of Formulation2
Application Interval3
Efficacy Rating
Resistance Risk
Fungicide and Formulation1

azoxystrobin + difenoconazole (Briskway)*

Amount of Formulation2

0.3 to 0.725

Application Interval3

14 to 21

Efficacy Rating

+++

Resistance Risk

Medium

Fungicide and Formulation1

azoxystrobin + propiconazole (Headway)
ME
G

Amount of Formulation2


0.75 to 3
2 ot 4 lbs

Application Interval3


7 to 28
14 to 28

Efficacy Rating

+++

Resistance Risk

Medium

Fungicide and Formulation1

azoxystrobin + tebuconazole (Strobe T) 2*

Amount of Formulation2

0.75 to 1.5

Application Interval3

14 to 21

Efficacy Rating

++++

Resistance Risk

Medium

Fungicide and Formulation1

boscalid (Emerald)*

Amount of Formulation2

0.13 to 0.18

Application Interval3

14 to 28

Efficacy Rating

++++

Resistance Risk

High

Fungicide and Formulation1

chlorothalonil
(Daconil Ultrex)*

(Daconil Weather Stik, Legend)*

(Daconil Zn)*

(Chlorothalonil 500ZN)*

(Chlorothalonil 720SFT)*

(Chlorothalonil)*

Amount of Formulation2


1 to 3.25
3.7 to 5
1 to 3.6
4 to 5.5
1.5 to 5
6 to 8
3 to 5
7.9
2.12 to 3.5
5.5
1.8 to 3.2

Application Interval3


7 to 21
14 to 21
7 to 21
14 to 21
7 to 21
14
7 to 14
14
7 to 14
14
7 to 10

Efficacy Rating

+++










Resistance Risk

Low










Fungicide and Formulation1

chlorothalonil + acibenzolar-S-methyl (Daconil Action)*

Amount of Formulation2

1 to 3.5
4 to 5.4

Application Interval3

7 to 21
14

Efficacy Rating

+++

Resistance Risk

Low

Fungicide and Formulation1

chlorothalonil + azoxystrobin (Renown)*

Amount of Formulation2

2.5 to 4.5

Application Interval3

7 to 14

Efficacy Rating

+++

Resistance Risk

Low

Fungicide and Formulation1

chlorothalonil + fluoxastrobin (Fame C)*

Amount of Formulation2

3 to 5.9

Application Interval3

14 to 21

Efficacy Rating

+++

Resistance Risk

High

Fungicide and Formulation1

chlorothalonil + iprodione + thiophanate-methyl + tebuconazole (Enclave)*

Amount of Formulation2

3 to 4
7 to 8

Application Interval3

14 to 21
28

Efficacy Rating

+++

Resistance Risk

Low

Fungicide and Formulation1

chlorothalonil + propiconazole (Concert)*

Amount of Formulation2

1.5 to 3
3 to 5.5
5.5 to 8.5

Application Interval3

7 to 10
14 to 21
14 to 28

Efficacy Rating

++++

Resistance Risk

Medium

Fungicide and Formulation1

chlorothalonil + propiconazole + fludioxonil (Instrata)*

Amount of Formulation2

2.75 to 6

Application Interval3

21 to 28

Efficacy Rating

++++

Resistance Risk

Medium

Fungicide and Formulation1

chlorothalonil + thiophanate-methyl
(Spectro)*
(TM/C)*

Amount of Formulation2


3.72 to 5.76
2 to 8

Application Interval3


14 to 21
7 to 14

Efficacy Rating

+++

Resistance Risk

Medium

Fungicide and Formulation1

fluazinam (Secure)*

Amount of Formulation2

0.5

Application Interval3

14

Efficacy Rating

+++

Resistance Risk

Low

Fungicide and Formulation1

fluoxastrobin (Fame)

Amount of Formulation2

0.18 to 0.36

Application Interval3

14 to 21

Efficacy Rating

++

Resistance Risk

High

Fungicide and Formulation1

fluoxastrobin + tebuconazole (Fame T)*

Amount of Formulation2

0.45 to 0.9

Application Interval3

21 to 28

Efficacy Rating

++++

Resistance Risk

Medium

Fungicide and Formulation1

fluxapyroxad (Xzemplar)

Amount of Formulation2

0.16 to 0.26

Application Interval3

14 to 28

Efficacy Rating

++++

Resistance Risk

High

Fungicide and Formulation1

iprodione (26GT, Iprodione Pro, IPro)*

Amount of Formulation2

2 to 4

Application Interval3

14 to 28

Efficacy Rating

+++

Resistance Risk

Medium

Fungicide and Formulation1

iprodione + thiophanate-methyl (26/36)*

Amount of Formulation2

2 to 4

Application Interval3

14 to 21

Efficacy Rating

+++

Resistance Risk

High

Fungicide and Formulation1

iprodione + trifloxystrobin (Interface)*

Amount of Formulation2

2 to 5

Application Interval3

refer to label

Efficacy Rating

++++

Resistance Risk

Medium

Fungicide and Formulation1

mancozeb
(Fore)*
(Dithane)*

Amount of Formulation2


6 to 8
6 to 8

Application Interval3


7 to 14
10

Efficacy Rating

+

Resistance Risk

Low

Fungicide and Formulation1

metconazole (Tourney)

Amount of Formulation2

0.18 to 0.37

Application Interval3

14 to 21

Efficacy Rating

+++

Resistance Risk

Medium

Fungicide and Formulation1

mineral oil (Civitas) + proprietary pigment (Civitas Harmonizer)*

Amount of Formulation2

(8 to 32) + (1 to 4)

Application Interval3

7 to 21

Efficacy Rating

++

Resistance Risk

Low

Fungicide and Formulation1

myclobutanil (Eagle, Myclobutanil)

Amount of Formulation2

0.5 to 2.4

Application Interval3

7 to 28

Efficacy Rating

++

Resistance Risk

Medium

Fungicide and Formulation1

penthiopyrad (Velista)

Amount of Formulation2

0.3 to 0.5

Application Interval3

14 to 21

Efficacy Rating

+++

Resistance Risk

High

Fungicide and Formulation1

propiconazole (Banner MAXX, Propiconazole)

Amount of Formulation2

0.5 to 2

Application Interval3

7 to 28

Efficacy Rating

+++

Resistance Risk

Medium

Fungicide and Formulation1

pyraclostrobin (Insignia)
WG
SC

Amount of Formulation2


0.9
0.7

Application Interval3


14
14

Efficacy Rating

++

Resistance Risk

High

Fungicide and Formulation1

pyraclostrobin + boscalid (Honor)*

Amount of Formulation2

0.83 to 1.1

Application Interval3

14 to 21

Efficacy Rating

++++

Resistance Risk

High

Fungicide and Formulation1

pyraclostrobin + fluxapyroxad (Lexicon Intrinsic)

Amount of Formulation2

0.34 to 0.47

Application Interval3

14 to 28

Efficacy Rating

++++

Resistance Risk

High

Fungicide and Formulation1

pyraclostrobin + triticonazole (Pillar G)

Amount of Formulation2

3 lbs

Application Interval3

14 to 28

Efficacy Rating

+

Resistance Risk

Medium

Fungicide and Formulation1

tebuconazole
(Torque)*
(Mirage)*
(Tebuconazole)*

Amount of Formulation2


0.6 to 1.1
1 to 2
0.6

Application Interval3


refer to label
14 to 28
28

Efficacy Rating

+++


Resistance Risk

Medium


Fungicide and Formulation1

thiophanate-methyl
(3336)
(3336 Plus)
(TM) WDG
(TM) L

Amount of Formulation2


2 to 4
2 to 4
0.67 to 1.3
1 to 2

Application Interval3


14
14 to 28
14
14

Efficacy Rating

++



Resistance Risk

High



Fungicide and Formulation1

triadimefon (Bayleton)

Amount of Formulation2

0.25 to 1

Application Interval3

14 to 30

Efficacy Rating

+++

Resistance Risk

Medium

Fungicide and Formulation1

trifloxystrobin + triadimefon
(Armada)
(Tartan)*

Amount of Formulation2


0.6 to 1.2
1 to 2

Application Interval3


14 to 28
14 to 28

Efficacy Rating

+++

Resistance Risk

High

Fungicide and Formulation1

triticonazole
(Trinity)
(Triton)
(Triton FLO)

Amount of Formulation2


1 to 2
0.15 to 0.3
0.28 to 1.1

Application Interval3


14 to 28
14 to 28
14 to 28

Efficacy Rating

+++


Resistance Risk

Medium


Fungicide and Formulation1

triticonazole + chlorothalonil (Reserve)*

Amount of Formulation2

3.2 to 4.5

Application Interval3

14 to 28

Efficacy Rating

++++

Resistance Risk

Medium

Fungicide and Formulation1

vinclozolin (Curalan, Touche)*

Amount of Formulation2

1

Application Interval3

21 to 28

Efficacy Rating

+++

Resistance Risk

Medium

1 Other trade names with the same active ingredients are labeled for use on turfgrasses and can be used according to label directions.
2 Apply fungicides in 2 to 5 gallons of water per 1,000 square feet according to label directions. Use lower rates for preventive and higher rates for curative applications.
3 Use shorter intervals when conditions are very favorable for disease.
* Products marked with an asterisk are not labeled for home lawn use.

Efficacy Rating
++++ = excellent control when conditions are highly favorable for disease development
+++ = good control when disease pressure is high, excellent control when disease pressure is moderate
++ = good control when disease pressure is moderate, excellent control when disease pressure is low
+ = good control when disease pressure is low
? = not rated due to insufficient data

Resistance Risk
Low = Rotate to different chemical class after 3-4 applications; tank mixing not necessary
Medium = Rotate to different chemical class after 1-2 applications; tank-mixing with low or medium risk product recommended
High = Rotate to different chemical class after EVERY application; tank-mix with low or medium risk product for EVERY application
? = not rated due to insufficient data

Presentations

Publications

Species Data

Host species

all

bermuda dollarspot2 ltc
bermuda dollarspot2 ltc
bermuda dollarspot2 ltc
bermuda dollar spot ltc
bermuda dollar spot ltc
bermuda dollar spot ltc
dollarspotbent3 ltc
dollarspotbent3 ltc
dollarspotbent3 ltc
dollarspotbent4 ltc
dollarspotbent4 ltc
dollarspotbent4 ltc
dollarspotbent ltc
dollarspotbent ltc
dollarspotbent ltc
dollarspot bent2 ltc
dollarspot bent2 ltc
dollarspot bent2 ltc
dollarspot bermuda1 ltc
dollarspot bermuda1 ltc
dollarspot bermuda1 ltc
dollarspot bermuda2 6 ltc
dollarspot bermuda2 6 ltc
dollarspot bermuda2 6 ltc
dollarspot bermuda2 ltc
dollarspot bermuda2 ltc
dollarspot bermuda2 ltc
dollarspot bermuda8 ltc
dollarspot bermuda8 ltc
dollarspot bermuda8 ltc
dollarspot centipede ltc
dollarspot centipede ltc
dollarspot centipede ltc
dollarspot in crenshaw ltc
dollarspot in crenshaw ltc
dollarspot in crenshaw ltc
dollarspot leisionsbermuda2 ltc
dollarspot leisionsbermuda2 ltc
dollarspot leisionsbermuda2 ltc
dollarspot lesionsbent4 ltc
dollarspot lesionsbent4 ltc
dollarspot lesionsbent4 ltc
dollarspot lesionsbent7 ltc
dollarspot lesionsbent7 ltc
dollarspot lesionsbent7 ltc
dollarspot mycelium kbg ltc
dollarspot mycelium kbg ltc
dollarspot mycelium kbg ltc
dollarspot zoysia 1 ltc
dollarspot zoysia 1 ltc
dollarspot zoysia 1 ltc
dollarspot zoysia ltc
dollarspot zoysia ltc
dollarspot zoysia ltc
dollar spot kbg ltc
dollar spot kbg ltc
dollar spot kbg ltc
field dollarspocentipedegrass ltc
field dollarspocentipedegrass ltc
field dollarspocentipedegrass ltc
field dollarspotzoysia ltc
field dollarspotzoysia ltc
field dollarspotzoysia ltc
field dollarspot bent3 ltc
field dollarspot bent3 ltc
field dollarspot bent3 ltc
field dollarspot crenshaw ltc
field dollarspot crenshaw ltc
field dollarspot crenshaw ltc
Months with symptoms

February to November

Stand symptoms

spots, patches (4 to 12 inches)

bermuda dollarspot2 ltc
bermuda dollarspot2 ltc
bermuda dollarspot2 ltc
bermuda dollar spot ltc
bermuda dollar spot ltc
bermuda dollar spot ltc
dollarspot14 ltc
dollarspot14 ltc
dollarspot14 ltc
dollarspot1 ltc
dollarspot1 ltc
dollarspot1 ltc
dollarspotbent3 ltc
dollarspotbent3 ltc
dollarspotbent3 ltc
dollarspotbent ltc
dollarspotbent ltc
dollarspotbent ltc
dollarspotdsc 2986 ltc
dollarspotdsc 2986 ltc
dollarspotdsc 2986 ltc
dollarspot bent2 ltc
dollarspot bent2 ltc
dollarspot bent2 ltc
dollarspot centipede ltc
dollarspot centipede ltc
dollarspot centipede ltc
dollarspot in crenshaw ltc
dollarspot in crenshaw ltc
dollarspot in crenshaw ltc
dollarspot ltc
dollarspot ltc
dollarspot ltc
dollarspot zoysia ltc
dollarspot zoysia ltc
dollarspot zoysia ltc
dollar spot kbg ltc
dollar spot kbg ltc
dollar spot kbg ltc
field dollarspotzoysia ltc
field dollarspotzoysia ltc
field dollarspotzoysia ltc
field dollarspot crenshaw ltc
field dollarspot crenshaw ltc
field dollarspot crenshaw ltc
Foliar symptoms location/shape

round leaf spots, leaf lesions

dollarspot3 ltc
dollarspot3 ltc
dollarspot3 ltc
dollarspotbent4 ltc
dollarspotbent4 ltc
dollarspotbent4 ltc
dollarspotbent ltc
dollarspotbent ltc
dollarspotbent ltc
dollarspot bermuda1 ltc
dollarspot bermuda1 ltc
dollarspot bermuda1 ltc
dollarspot bermuda2 6 ltc
dollarspot bermuda2 6 ltc
dollarspot bermuda2 6 ltc
dollarspot bermuda2 ltc
dollarspot bermuda2 ltc
dollarspot bermuda2 ltc
dollarspot bermuda8 ltc
dollarspot bermuda8 ltc
dollarspot bermuda8 ltc
dollarspot leisionsbermuda2 ltc
dollarspot leisionsbermuda2 ltc
dollarspot leisionsbermuda2 ltc
dollarspot lesionsbent4 ltc
dollarspot lesionsbent4 ltc
dollarspot lesionsbent4 ltc
dollarspot lesionsbent7 ltc
dollarspot lesionsbent7 ltc
dollarspot lesionsbent7 ltc
dollarspot mycelium ltc
dollarspot mycelium ltc
dollarspot mycelium ltc
dollarspot whitemycellium ltc
dollarspot whitemycellium ltc
dollarspot whitemycellium ltc
dollarspot zoysia 1 ltc
dollarspot zoysia 1 ltc
dollarspot zoysia 1 ltc
field dollarspocentipedegrass ltc
field dollarspocentipedegrass ltc
field dollarspocentipedegrass ltc
field dollarspot leaflesionskbg 3 ltc
field dollarspot leaflesionskbg 3 ltc
field dollarspot leaflesionskbg 3 ltc
field dollarspot leaflesionskbg2 ltc
field dollarspot leaflesionskbg2 ltc
field dollarspot leaflesionskbg2 ltc
Foliar symptoms color

tan or white

dollarspot3 ltc
dollarspot3 ltc
dollarspot3 ltc
dollarspotbent4 ltc
dollarspotbent4 ltc
dollarspotbent4 ltc
dollarspotbent ltc
dollarspotbent ltc
dollarspotbent ltc
dollarspot bermuda1 ltc
dollarspot bermuda1 ltc
dollarspot bermuda1 ltc
dollarspot bermuda2 6 ltc
dollarspot bermuda2 6 ltc
dollarspot bermuda2 6 ltc
dollarspot bermuda2 ltc
dollarspot bermuda2 ltc
dollarspot bermuda2 ltc
dollarspot bermuda8 ltc
dollarspot bermuda8 ltc
dollarspot bermuda8 ltc
dollarspot leisionsbermuda2 ltc
dollarspot leisionsbermuda2 ltc
dollarspot leisionsbermuda2 ltc
dollarspot lesionsbent4 ltc
dollarspot lesionsbent4 ltc
dollarspot lesionsbent4 ltc
dollarspot lesionsbent7 ltc
dollarspot lesionsbent7 ltc
dollarspot lesionsbent7 ltc
dollarspot mycelium kbg ltc
dollarspot mycelium kbg ltc
dollarspot mycelium kbg ltc
dollarspot mycelium ltc
dollarspot mycelium ltc
dollarspot mycelium ltc
dollarspot whitemycellium ltc
dollarspot whitemycellium ltc
dollarspot whitemycellium ltc
dollarspot zoysia 1 ltc
dollarspot zoysia 1 ltc
dollarspot zoysia 1 ltc
field dollarspocentipedegrass ltc
field dollarspocentipedegrass ltc
field dollarspocentipedegrass ltc
field dollarspot leaflesionskbg 3 ltc
field dollarspot leaflesionskbg 3 ltc
field dollarspot leaflesionskbg 3 ltc
field dollarspot leaflesionskbg2 ltc
field dollarspot leaflesionskbg2 ltc
field dollarspot leaflesionskbg2 ltc
Root/Crown symptoms

none

Fungal Signs

mycelium or none

dollarspotbent4 ltc
dollarspotbent4 ltc
dollarspotbent4 ltc
dollarspot mycelium kbg ltc
dollarspot mycelium kbg ltc
dollarspot mycelium kbg ltc
dollarspot mycelium ltc
dollarspot mycelium ltc
dollarspot mycelium ltc
dollarspot whitemycellium2 ltc
dollarspot whitemycellium2 ltc
dollarspot whitemycellium2 ltc
dollarspot whitemycellium ltc
dollarspot whitemycellium ltc
dollarspot whitemycellium ltc