Diseases ›

Microdochium Patch

Symptoms

Pink snow mold develops during periods of snow cover, with symptoms of the disease becoming evident as the snow melts. The disease appears in roughly circular patches from 2 inches to 1 foot in diameter that are white or light tan in color. A ring of salmon or pink-colored growth is present on the outer edge of patches when the disease is actively developing. The infected leaves within the patches are usually collapsed and matted down upon themselves.

Development Factors

Disease activity is most severe when snow falls on unfrozen ground; however, activity can occur without snow cover during cool (less than 60°F) wet weather. Excessive foliar growth and thatch buildup are the most important factors encouraging development of pink snow mold and Microdochium patch. Restricted air movement, poor soil drainage, inadequate levels of potassium, and heavy traffic can also enhance the disease. The disease may also develop under tree leaves that remain on the turf for long periods during cold, wet weather.

Cultural Control

Do not apply nitrogen when cold weather is expected or before the first expected prolonged snow cover. Continue mowing in the fall until foliar growth stops completely. These steps will prevent a buildup of lush foliage that is highly prone to pink snow mold or Microdochium patch.

Improve surface drainage, control traffic patterns, reduce thatch accumulations, and aerify regularly in areas that have been severely affected by the disease in the past. Prune trees and remove unwanted vegetation that impedes air movement. Frequently remove leaves and other debris during autumn and winter from turf that is not covered with snow.

In regions where heavy snow is anticipated, take steps to minimize the duration of snow cover. Erect snow fences or plant landscape plants in strategic locations to prevent excess snow accumulation. Prevent traffic on snow-covered turf, as compacted snow will melt more slowly and increase damage from pink snow mold.

Chemical Control

Fungicides are effective for control of pink snow mold and Microdochium patch. In the case of pink snow mold, apply fungicides before snow cover to prevent disease development. Mapping and spot-treatment of areas where pink snow mold is most severe can significantly reduce fungicide expenditures. In regions where prolonged snow cover does not occur, apply fungicides when symptoms of Microdochium patch are first observed.

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

azoxystrobin
(Heritage, Strobe)

(Heritage TL)

(Heritage G)

(Strobe L)

Amount of Formulation2


0.2 to 0.4
0.7
2
3.5
4 lbs
7 lbs
0.77
1.35

Application Interval3


10 to 28
1 application
42305
1 application
10 to 28
1 application
14
1 application

Efficacy Rating

++







Resistance Risk

Medium







Fungicide and Formulation1

azoxystrobin + acibenzolar-S-methyl (Heritage Action)*

Amount of Formulation2

0.4

Application Interval3

refer to label

Efficacy Rating

++

Resistance Risk

Medium

Fungicide and Formulation1

azoxystrobin + chlorothalonil (Renown)*

Amount of Formulation2

2.5 to 4.5

Application Interval3

14 to 21

Efficacy Rating

++

Resistance Risk

Low

Fungicide and Formulation1

azoxystrobin + difenoconazole (Briskway)*

Amount of Formulation2

0.5 to 0.725

Application Interval3

14 to 28

Efficacy Rating

++

Resistance Risk

Medium

Fungicide and Formulation1

azoxystrobin + propiconazole (Headway)
ME

G

Amount of Formulation2


1.5 to 3
5.25
2 to 4 lbs
5

Application Interval3


10 to 28
1 application
14 to 28
1 application

Efficacy Rating

++++



Resistance Risk

Medium



Fungicide and Formulation1

azoxystrobin + tebuconazole (Strobe T)*

Amount of Formulation2

0.75 to 1.5
2.4

Application Interval3

14 to 21
1 application

Efficacy Rating

++++

Resistance Risk

Medium

Fungicide and Formulation1

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

Amount of Formulation2

5.4

Application Interval3

21 to 28

Efficacy Rating

++

Resistance Risk

Low

Fungicide and Formulation1

chlorothalonil + fluoxastrobin (Fame C)*

Amount of Formulation2

3 to 5.9

Application Interval3

28

Efficacy Rating

++

Resistance Risk

Medium

Fungicide and Formulation1

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

Amount of Formulation2

7 to 8

Application Interval3

28

Efficacy Rating

++++

Resistance Risk

Low

Fungicide and Formulation1

chlorothalonil + propiconazole (Concert)*

Amount of Formulation2

8.5

Application Interval3

14 to 28

Efficacy Rating

++++

Resistance Risk

Low

Fungicide and Formulation1

chlorothalonil + propiconazole + fludioxonil (Instrata)*

Amount of Formulation2

5 to 11

Application Interval3

late fall

Efficacy Rating

++++

Resistance Risk

Low

Fungicide and Formulation1

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

Amount of Formulation2


6 to 8
3.72 to 5.76

Application Interval3


1 application
14

Efficacy Rating

+++

Resistance Risk

Medium

Fungicide and Formulation1

fluazinam (Secure)*

Amount of Formulation2

0.5

Application Interval3

late fall

Efficacy Rating

+++

Resistance Risk

Low

Fungicide and Formulation1

fludioxonil (Medallion)

Amount of Formulation2

0.25 to 0.5

Application Interval3

14

Efficacy Rating

+++

Resistance Risk

Low

Fungicide and Formulation1

fluoxastrobin (Fame)
SC
G

Amount of Formulation2


0.18 to 0.36
2.3 to 4.6 lbs

Application Interval3


14 to 28
14 to 28

Efficacy Rating

+

Resistance Risk

Medium

Fungicide and Formulation1

fluoxastrobin + tebuconazole (Fame T)*

Amount of Formulation2

0.45 to 0.9

Application Interval3

30

Efficacy Rating

++++

Resistance Risk

Medium

Fungicide and Formulation1

fluxapyroxad (Xzemplar)

Amount of Formulation2

0.26

Application Interval3

14 to 28

Efficacy Rating

++

Resistance Risk

Medium

Fungicide and Formulation1

flutolanil + thiophanate-methyl (SysStar)

Amount of Formulation2

4 to 6.12
2 to 3

Application Interval3

1 application
14 to 21

Efficacy Rating

+++

Resistance Risk

Medium

Fungicide and Formulation1

iprodione (26GT, Iprodione Pro, IPro)*

Amount of Formulation2

4 to 8

Application Interval3

1 to 2 applications

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

Medium

Fungicide and Formulation1

iprodione + trifloxystrobin (Interface)*

Amount of Formulation2

4 to 7

Application Interval3

1 application

Efficacy Rating

++++

Resistance Risk

Medium

Fungicide and Formulation1

mancozeb
(Fore)*
(Dithane)*

Amount of Formulation2


6 to 8
6 to 8

Application Interval3


14 to 42
14 to 42

Efficacy Rating

+

Resistance Risk

Low

Fungicide and Formulation1

metconazole (Tourney)

Amount of Formulation2

0.37 to 0.44

Application Interval3

late fall

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

PCNB
WP
G
F

Amount of Formulation2


3 to 8
80 to 160
12 to 16

Application Interval3


28 to 42
prior to snowfall
prior to snowfall

Efficacy Rating

++++


Resistance Risk

Low


Fungicide and Formulation1

propiconazole (Banner MAXX, Propiconazole)

Amount of Formulation2

2 to 4

Application Interval3

fall to early spring

Efficacy Rating

++++

Resistance Risk

Medium

Fungicide and Formulation1

pyraclostrobin (Insignia)
WG
SC

Amount of Formulation2


0.5 to 0.9
0.7

Application Interval3


14 to 28
14 to 28

Efficacy Rating

+++

Resistance Risk

Medium

Fungicide and Formulation1

pyraclostrobin + boscalid (Honor)*

Amount of Formulation2

0.55 to 1.1

Application Interval3

14 to 28

Efficacy Rating

+++

Resistance Risk

Medium

Fungicide and Formulation1

pyraclostrobin + fluxapyroxad (Lexicon Intrinsic)

Amount of Formulation2

0.47

Application Interval3

14 to 28

Efficacy Rating

+++

Resistance Risk

Medium

Fungicide and Formulation1

pyraclostrobin + triticonazole (Pillar G)

Amount of Formulation2

3 lbs

Application Interval3

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


prior to snowfall
10 to 28
prior to snowfall

Efficacy Rating

+++


Resistance Risk

Medium


Fungicide and Formulation1

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

Amount of Formulation2


2 to 4
2 to 4
0.67 to 1.3
1.5 to 6 lbs
1 to 2

Application Interval3


14
14 to 28
14
14
14

Efficacy Rating

+++




Resistance Risk

Medium




Fungicide and Formulation1

trifloxystrobin (Compass)

Amount of Formulation2

0.2 to 0.25

Application Interval3

fall to early spring

Efficacy Rating

+++

Resistance Risk

Medium

Fungicide and Formulation1

trifloxystrobin + triadimefon
(Armada)
(Tartan)*

Amount of Formulation2


1.2
2

Application Interval3


fall to early spring
fall to early spring

Efficacy Rating

+++

Resistance Risk

Medium

Fungicide and Formulation1

triticonazole
(Trinity)
(Triton)
(Triton Flo)

Amount of Formulation2


0.5 to 2
0.15 to 0.3
0.28 to 1.1

Application Interval3


14 to 28
late fall
10 to 14

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

Low

Fungicide and Formulation1

vinclozolin (Curalan, Touche)*

Amount of Formulation2

1

Application Interval3

10 to 21

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

bentgrass, bermudagrass, bluegrasses

microdochium patchbent4 ltc
microdochium patchbent4 ltc
microdochium patchbent4 ltc
microdochium patchbent5 ltc
microdochium patchbent5 ltc
microdochium patchbent5 ltc
microdochium patchbent6 ltc
microdochium patchbent6 ltc
microdochium patchbent6 ltc
Months with symptoms

November to March

Stand symptoms

spots, circles, patches (4 to 12 inches)

microdochiumpatch dsc 1696 ltc
microdochiumpatch dsc 1696 ltc
microdochiumpatch dsc 1696 ltc
microdochiumpatch dsc 1706 ltc
microdochiumpatch dsc 1706 ltc
microdochiumpatch dsc 1706 ltc
microdochium patch1 ltc
microdochium patch1 ltc
microdochium patch1 ltc
microdochium patch2 ltc
microdochium patch2 ltc
microdochium patch2 ltc
microdochium patch3 ltc
microdochium patch3 ltc
microdochium patch3 ltc
microdochium patch9 ltc
microdochium patch9 ltc
microdochium patch9 ltc
microdochium patchbent4 ltc
microdochium patchbent4 ltc
microdochium patchbent4 ltc
microdochium patchbent5 ltc
microdochium patchbent5 ltc
microdochium patchbent5 ltc
microdochium patchbent6 ltc
microdochium patchbent6 ltc
microdochium patchbent6 ltc
microdochium patch ltc
microdochium patch ltc
microdochium patch ltc
Foliar symptoms location/shape

blighting of entire leaves

Foliar symptoms color

pink, white, tan

Root/Crown symptoms

none

Fungal Signs

mycelium, jelly-like spore-masses