Turf Notes
SPRING 2013
Introduction
The arrival of spring is a busy time for Course Superintendents. In this edition of Turf Notes we revisit
that on-going problem, moss.
SPRING (AUGUST - NOVEMBER) Management Requirements
Northern Region
Central Region
Southern Region
1. Black beetle
The hot dry summer of 2013, means
there is a strong likelihood that Black
beetle will be a problem on turf this
summer. Spring is the ideal time to
start both monitoring and potentially
control programmes (refer to
November 2012 Turf Management
Journal).
1. Black beetle
Hamilton north & coastal
areas in the NI should consider
a monitoring programme
(refer to November 2012 Turf
Management Journal).
2.Dry patch control
(Refer Southern region)
1. Dry patch control
Ensure any dry patch affected
areas (i.e. where dew doesn’t form
or known problem areas from last
summer) are fully re-wetted (150200mm+) by mid-October/
November (refer Spring 2012
Turf Notes).
3.Porina
Taupo South, start monitoring
from approximately midOctober for the first flights of Porina.
2.Porina
Start monitoring from approximately
mid-October for the first flights of
Porina especially those areas north
of South Canterbury.
4.Renovation
(Refer to Northern region)
3.Moss control
Control is best carried out in spring,
thereby enabling a full turf cover to be
re-established prior to the next winter.
2.Dry patch control
(Refer Southern region)
3.Renovation
Consider organic matter testing to
assist with establishing renovation
goals & monitoring progress.
4.Sprinkler system
(Refer to Central region)
5.Sprinkler system
Complete a pre-season check
of irrigation system to ensure
system is working correctly
and providing uniform cover.
Specifically check:
• Sprinkler arcs are correctly
adjusted
• Sprinklers are perpendicular
and lift adequately
above turf surface
• Sprinklers are turning
correctly
• Sprinklers aren’t
leaking
• Sprinkler filters
are clean
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4.Renovation
(Refer to Northern region)
5.Sprinkler system
(Refer to Central region)
6.Fusarium patch & Cool season
brown patch may occur if spring
growth is slow.
7.Shading issues
Spring – summer is a good
time to address shade
related problems that
are occurring on greens
(refer Winter 2013
Turf Notes).
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MOSS CONTROL
Introduction
Moss, particularly silver moss (Bryum argenteum)
is a common problem on golf greens. Generally it
starts off as a few isolated ‘cushions’ and can within
a couple of seasons develop into a widespread
problem, severely compromising ball roll.
The very dense nature of silver moss (compared to
the other mosses) makes it difficult for chemicals
to penetrate deep enough into the ‘cushions’
and hence kill the moss. Consequently, control
programmes often produce variable results.
Life Cycle
Silver moss (& the green mosses) go through two distinct growth phases. The juvenile (colonising)
phase primarily occurs during summer – early autumn and is difficult to distinguish from algal slime.
This phase is most commonly a green coloured thread - like skin but it may also take on a brownish look.
?
To determine whether it is colonising moss or slime, drag a
pin or needle through the area. If the needle gathers threads
around it, then it is colonising moss not algal slime.
Why is this important? The juvenile
phase is much easier control.
During autumn (March onwards) and once
the first dews are observed, the mature
cushions of silver moss start to form.
These initially start as single filaments of
silver moss growing out of the ‘slime’ and
with autumn rains these filaments rapidly
develop to form cushions of moss.
The juvenile phase of silver moss is most evident during summer
– early autumn and is often very difficult to distinguish from Algal slime.
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Preventative management
Moss ingression into greens is symptomatic of an existing problem. Successful long term control relies
not on simply spraying, but also addressing the cause /reasons behind its ingression. The main conditions that contribute to silver moss are as follows:
1. Cover
Mosses are colonising plants and therefore are usually the first plants to establish in any weak or bare
areas that are present.
Typically silver moss is commonly seen in:
• dry patch affected areas,
• old disease scars,
• triplex rings on the green’s perimeters,
• high traffic areas,
• waterlogged areas on greens,
• thatchy greens that are consistently cut too close and areas where either the cover is thin
(e.g. mounds) and/or is lost.
2. Mowing
Despite what appears to be a complete turf cover, the low and frequent mowing required on greens provides an opportunity for light to reach the soil surface and allow moss to establish. This is most
evident in the ‘triplex ring’ and on mounding/tiers present within a green. Raising the height even a very
small amount (0.25-0.50mm) when cutting at very low heights(less than 3.5mm) will significantly
improve the plant’s ability to compete.
3. Thatch or organic matter
Excessive thatch (organic matter), poor dilution with sand or soil and layering within the profile all result
in high moisture contents and this in turn favours moss. The impact that organic matter accumulation
has on surface moisture content/retention is shown in the table below:
Organic Matter Test Results
Green A
Green B
Sample
depth (mm)
Organic
matter %
Moisture
content %
Sample
depth (mm)
Organic
matter %
Moisture
content %
0 – 10mm
2.8%
28%
0 – 10mm
12.1%
68%
10 – 20mm
4.5%
34%
10 – 20mm
7.0%
50%
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A sound approach to renovation which targets
and dilutes thatch is critical when reducing
the incidence of moss. In addition, a frequent
topdressing programme that is based on growth
rate (not a calendar basis) is required.
The effect of organic matter is graphically
illustrated in the photo to the left, where “free”
water is oozing out of thatch layer, but the sand
zone under the thatch is not saturated.
Effect of thatch on moisture retention
4. Fertility
Mosses lack a true root system. Consequently, fertilisers such as lime, phosphate, organic products and controlled release nitrogen sources that remain on or near the green surface especially if the surface cover is thin, during the early autumn when silver moss is establishing can make the
problem worse.
Control - Healthy and complete turf cover
The first priority is to maintain a complete and healthy turf cover. Issues that need to be managed if silver moss is to be discouraged, include:
• Managing dry patch areas (refer Spring Turf Notes, 2012).
• Adopting a sensible mowing height and when growth is slow, mowing frequency particularly in
high wear areas such as the triplex ring needs to be carefully managed (reduced).
• Renovation needs to clearly identify and address the limiting factors. Emphasis is on improving
drainage, organic matter dilution and re-establishing a complete cover (where necessary).
• In areas of the country where there is minimal if any winter growth, it is important to have the desired turf density for winter, by late summer/early autumn.
Chemical control - Juvenile moss slime (thread - like) stage
For those clubs that have a weak cover going into autumn and prior to the cushions of moss forming
consider the following strategies:
• Use acidic soluble fertilisers such as potash, ammonium sulphate and iron sulphate from early
autumn. Delay the use of NPK fertilisers until late autumn once a full cover has been re-established.
• Apply contact fungicides (Thiram, Orthocide, Mancozeb/Maneb) during late January – early March
at recommended rates for Algal slime. For example: Mancozeb (800gai/kg) @ 200 – 250g/100m2.
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Adult moss (cushion stage)
For best results when controlling moss:
i. To ensure the product penetrates to the base of the moss cushion, the moss must be thoroughly
saturated (i.e. when lightly touched water should ooze from the moss).
ii. Consider grooming (verti-cutting, groomer reel or rake) the greens prior to spraying, thereby opening
up the moss and aiding penetration of the mosskiller.
iii. Use appropriate water rates. Most products specify water rates of around 1000L/ha.
iv. The moss needs to remain moist for 2 – 3 days following spraying, in order to prolong the herbicide
effect. If necessary (particularly with autumn control programmes) consider syringing the greens
around 12.00 noon, 3.00pm and 5.00pm.
v. The dead moss needs to be thinned out to allow the turf to grow back through. Additionally the
turf needs to be actively growing so that a complete turf cover is re-established quickly following
treatment and reinfection by new moss colonies is reduced or prevented. A common issue,
particularly in cooler areas, is that the autumn rains don’t occur early enough and by the time moss
control is completed there is inadequate time for the turf to recover fully. Spring control is a better
timing in this instance.
Chemical options include:
Chemical Options for Controlling Moss
Active ingredient
Product names
Rate /100m2
Comment
Benzalkonium chloride – 500g/L
Surrender, Yield
250 - 500mls
Do not apply to young grass. Ensure grass is
actively growing.
Carfentrazone-ethyl – 240g/L
Hammer, Smack
Down, Affinity
Force
5mls
Apply two applications 14 – 20 days apart.
Will suppress both Kikuyu and Hydrocotyle.
Dichlorophen – 432g/L
Mostox
500 –
1000mls
Iron sulphate
Iron sulphate
300 – 400g
NZSTI Contact Details
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H A M I LTO N
PALMERSTON NORTH
Alex Glasgow
Everett Darlington
Spencer Myer
David Ormsby
Andrew Mitchell
09 415 0302
027 496 2486
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027 232 4545
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027 521 4954
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027 442 8053
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PA LM E RSTO N N O RTH
PALMERSTON NORTH
CH R I STCH U RCH
DU N E D I N
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Chris Gribben
Megan Cushnahan
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David Howard
06 355 7024
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027 552 4488
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027 220 9957
[email protected]
03 343 8966
027 446 2874
[email protected]
03 477 7333
027 446 2875
[email protected]
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