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Category: Greenkeeping

Bowls Green Turf Disease

There is a lot of confusion about fungal turf diseases.

The main issues that worry many people are as follows:

  • Accurate disease identification; not sure what we have so don’t know what to use.
  • Contamination being brought onto a clean green from a diseased green via bowlers’ feet and/or contractors machinery.
  • Fungicide rotation to prevent immunity
  • Repeat infection of greens
  • Disease Forecasts and what to do about them.

Let’s have a look at these in order:

Accurate Disease Identification.

Although it is always prudent to make sure you know exactly what fungal disease you have, the fact remains is that you have a fungal disease on your green and regardless of what it is, it is merely a symptom of other factors. So the urgent requirement is to stop it spreading any further. Broad spectrum fungicides do exactly as you would imagine, they kill most fungal pathogens so if you are using an up to date contact fungicide, you will more than likely be successful in stopping the disease with an application.

However, this is analogous with continually taking pain killers, but never going to the doctor to find out what is causing the pain. There are some more in-depth articles on symptoms and causes on bowling greens here.

Contamination by feet or machinery.

This crops up several times a year in my travels. I even see trays of disinfectant being left out for bowlers to walk through before going onto the green…and unfortunately the green is more likely to be adversely affected by the disinfectant than anything that could possibly come in on a machine or shoe.

The fact is that many of the common fungal disease pathogens like fusarium, red-thread, anthracnose etc are already present in your green, but they only cause problems when we make the conditions favourable for them, by allowing the green to become excessively thatchy and/or weak and waterlogged.

Fungicide rotation/ repeat Infection

Last year I visited a golf course to give advice. They were looking for an expert witness to prove that a manager had made the wrong decision in using the same fungicide two years in a row and now the greens were riddled with fusarium.

The greens were truly awful but the club had missed the point completely. The issue wasn’t the incorrect selection of chemical; it was the blind reliance on treating symptoms instead of working towards a healthy sward/soil relationship.

There was in excess of 3 inches of smelly, waterlogged, yellow, anaerobic thatch on every green. There isn’t a fungicide in the world that could keep disease at bay in such conditions.

Disease Forecasting

I know this scare-mongering tactic has caught on in recent years as a fungicide selling tool, but come on! This is absolute nonsense for all of the reasons noted above. Regardless of what the disease forecast says; if your green is in healthy condition as per our performance green standard, disease will not get a hold to any detrimental degree.

There are more in depth articles on turf disease, its causes and cures here.

Performance Bowls Green Maintenance Schedule

A few readers have asked for guidance on what work they should be carrying out on the green on a month to month basis.

Now of course conditions across the UK are widely varied at the moment; some areas in the south are free from frost, whilst here in Perthshire we can have very hard ground and many days of minus temperatures, in the southern parts of the country things can be and often are a lot milder.

When there is frost or snow cover its simply a waiting game; it really is best not to try to remove snow or ice from the green for two reasons:

  1. the damage that could be caused to the turf and soil by actually doing this work.
  2. the snow is affording the turf some protection from the worst of the cold weather; see my article on winter green protection here.

However, after the snow has gone and you start to see a prolonged period of thaw there are a few things you need to look out for as follows: Read more

Problems with Bowls Greens

Yes there are, but they are actually few in number and most of them are symptoms of the big 2.

Fusarium, Localised Dry Patch, Thatch Fungus, Compaction, Spongy Surface, Slow Green, Bumpy Surface, Anthracnose Disease, Dollar Spot, Thatch, Slime, Algae, Fairy Ring, Moss, Leatherjackets, Poor grass growth, Annual Meadow Grass, Weeds, Pearlwort, Angry members, Excessive water costs, etc etc…blah blah blah.

I could go on for a long time with that list.

This is another composite question from the search results on the site this month. About 40 people so far have typed in something like “I’ve got problems on my bowling green”

As regulars know there are only 2 problems on bowling greens; thatch and compaction and everything else is simply a symptom of these two.

So the question should maybe be:

How do bowling greens succumb to thatch and compaction?

Answer: Inappropriate Maintenance Practices.

The Circle of Decline explains this fully.

Performance Bowls Greens and Money Saving

The autumn is traditionally a busy time for bowling green contractors, greenkeepers and club officials as they decide, plan and carry out the autumn renovation works on the green before putting it to bed for the winter.

Now have a look back over that last paragraph; if you didn’t wince at least twice, then it’s possible that you are about to embark on a program of work that will actually harm your green.

It probably won’t be dramatic like the sudden death of your green for ever, but it will probably have a negative impact on the future of your green’s ability to be presented for play consistently well, and maybe even on your club’s chance of survival in these harsh economic conditions.

The points I am referring to are Read more

Paspallum Stolon

Turf grass growth characteristics and habits

I often talk about close mowing here on bowls central and don’t usually recommend a cutting height of less than 4.5mm even in perfect growing conditions. Of course the mower blades will have been set higher during the recent very dry and very hot weather to allow the plants to retain more leaf area and therefore more moisture. An understanding of turf grass growth characteristics is important in helping you to make the correct maintenance decisions.

Crown
Another reason for avoiding excessively close mowing is the irreversible damage that can be done to the grass plant, especially if the crown is damaged. The plant can survive a lot of trauma as long as the crown remains intact, so great care should be taken to avoid scalping the green too close.

In my recent post about turf grass shoot structures I mentioned the plant stem as one particular shoot structure used by turf grass plants. You can think of the crown of the grass plant as a stem that has been squashed down, concertina style to the ground. All of the internodes where leaves arise are stacked alternately into a very compact stem that barely rises above the soil surface. This critical part of the grass plant includes the upper stem apex and the same bud meristems (where new shoots arise) as the longer stems we looked at before, only in this form the nodes are all tightly stacked with no elongation of the internodal area to speak of. Finally there are the lower meristematic nodes and it is here that the plant can initiate new roots and shoots.

Lateral Shoots
New lateral shoots can be initiated from vegetative meristems or buds in the base of leaves or from stem nodes, rhizomes or stolons. These lateral shoots can be tillers, stolons or rhizomes depending on species and conditions.

Intravaginal Growth
Young stems can grow out from the basal sheath of the the grass leaf and this is called intravaginal growth.

Tillers
The main turf grass plant characteristic that allows the formation of dense sports turf is that of tillering. Tillers originate intravaginally from the plant stem and can be encouraged by

  •     mowing below 30mm
  •     ready availability of Nitrogen
  •     good sunlight levels and reduced shade
  •     good carbohydrate reserves in the plant (strong photosynthesis activity)

Some grass species employ tillering exclusively and therfore form a bunch type growth habit. These include colonial bentgrass, hard fescue, sheep’s fescue, chewings fescue, annual ryegrass, perenneial ryegrass and annual meadowgrass.

Extravaginal Growth
Extravaginal growth is when young stems grow vegatatively by pushing through the lower part of the basal leaf sheath. This type of growth is split into two main groups:

Stolons

A stolon is a secondary shoot that grows extravaginally above ground with considerable elongation of the stem horizontally.

  • this allows the plant to initiate a spreading (sometimes called creeping) growth habit.
  • creates a secondary carbohydrate reserve for emergencies
  • creates opportuities for spreading vegatively as each node on the stem can produce new daughter plants by producing roots and shoots.
  • increases the knitting together and strength of the turf.

Common stoloniferous grasses include velvet bentgrass and creeping bentgrass

Rhizomes
Rhizomes are similar to stolons except that they break through the leaf basal sheaf below ground and spread by means of elongated underground lateral stems. This characteristic:

  • gives the plant a strong lateral, spreading growth habit.
  • adds to turf strength and integrity
  • provides a secondary carbohydrate store for emergency growth requirements
  • helps turf to have a strong recuperative potential from wear and injury
  • allows for improved dormancy survival after heat and drought
  • initiates new plants at stem nodules in the same way that stolons do except underground.

Rhizomatous grass plants grow strongly when conditions provide for their optimum temperature ranges (150-240C for cool season and 270-350C for warm season grasses). Long day length, high light intensity and lower nitrogen availability also favour their success.

To provide the thickening of turf density the rhizome must turn upwards towards the surface to allow for new shoots to be initiated and this is favoured by light exposure (e.g. by aeration, brushing etc), low CO2 levels in the soil (aeration), heat stress (not over watering), shorter photo period (day length) and good nitrogen availability.

The rhizomatous grasses include many of the red fescues and smooth stalked meadow grass.

Integrated Secondary Lateral Growth Habits
Many of the most commonly used warm season turf grasses employ stolons and rhizomes to create a very vigorous and tight knit turf that recuperates well from stress and provides high wear tolerance. These include many of the Bermuda, Zoysia and Seashore Paspallum grasses.

Inflorescence

Annual Meadowgrass
Annual Meadowgrass inflorescence on bowling green (photo by S Kennerley)

This is the structure put up by the plant in order to create and spread its seed. It is an erect flowering structure and the seeds are formed on individual spikelets of it. Shortenting day length and cooling temperatures initiate this in cool season grasses. This isn’t usually a feature of quality turfgrass as it depends on grass being allowed to grow naturally to its full height, but it can be seen in turf on annual meadow grass in the spring and early summer.

If you have anything to add or any questions please leave a comment or drop me a line.