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a lot of hot air?

Air is a very important component of a Performance Bowling Green.

50% of a healthy, performance green will be air; 25% Micro-pores and 25% Macro-pores.

The Macro Pore or “aeration” space is where drainage happens.

The Micro-Pore or “capillary” space is where grass plant roots get their water and nutrients.

Tip the balance in favour of one or the other of these and things start to go wrong.

Compaction reduces the Macro air space in soil and inhibits drainage and root penetration. The soil now holds on to too much moisture and a whole raft of other problems ensue; particularly the build up of excessive thatch due to the anaerobic (lacking in oxygen) soil conditions brought about by the reduction in air space.

Thatch becomes a breeding ground for fungal disease and a base for Localised Dry Patch to take hold. The thatch doesn’t break down naturally as it should because there is a massive reduction in the population of aerobic soil microbes and they usually do this job.

Tip the balance the other way by applying excessive amounts of sand top-dressing and there is now too much air space, there is very little capillary space and the green starts to dry out too quickly. Localised Dry Patch now takes over, the surface is unpredictable and the soil can’t provide the nutrition the plants need naturally any more.

Yes, for a healthy living green that performs to order you need a lot of space; 50% air space.

Luckily, a healthy living soil knows how to do all of this without us.

We are only needed to help rectify the damage we inflict, which is mainly compaction and nutrient depletion through the removal of grass clippings.

Ahh! how simple!

ecology

Bowls Greens don’t have beds!

I often hear the phrase “putting the green to bed” at this time of year.

It is the most frustrating thing to hear because I don’t know of any club that can afford the luxury of stopping work on the green now.

The autumn and winter period is the most important time to get on top of a range of big problems that blight bowling greens.

For example Thatch encourages diseases such as fusarium, insect pests like leatherjackets and chafer grubs and contributes significantly to the onset of Localised Dry Patch the modern scourge of bowling greens throughout the UK. As if that wasn’t enough excessive thatch also saps the speed from your green and causes heavy, unpredictable rinks, contributes to un-even surfaces, causes bumpiness and bad rinks, reduces the efficacy of fertilisers and encourages weed grasses such as annual meadow grass to predominate the sward.

Then there is Compaction which impedes natural drainage, causes shallow rooting of grasses (which leads to skinning on heads), impedes irrigation and rain penetration and causes root break. And that’s before we even consider its expertise at encouraging weed grasses such as annual meadow grass, its ability to severely reduce the efficiency of irrigation, efficacy of fertilisers and its major contributory role in the creation of un-even surfaces and loss of grass cover on edges and heads.

If you only deal with these two issues this winter you will have gone a long way towards creating a performance green; they won’t go away by giving the green “a rest”.

I recently uploaded a new 18 page special report on autumn and Winter Maintenance of the Bowling Green to the Shop which shows you how to deal with thatch and compaction this Autumn and Winter as well as a host of other problems like Insect Pests, Fungal Disease, Localised Dry Patch and Moss.

Localised Dry Patch Update

LDP Affected green after heavy rain

Already the relatively dry April and start to May has seen bowling greens suffering from Localised Dry Patch (LDP).

As we have discussed many times on this site before, this condition is a major problem for bowling clubs throughout the UK and if your bowling green is aready showing the tell tale signs then you need to take rapid and relentless action to avoid major disruption to your bowling green surface this season.

Meantime for greens already showing signs of the problem here is my Read more

Localised Dry Patch-a modern plague killing bowls greens

dry patch
LDP Affected green after heavy rain

Localised Dry Patch (LDP) is a condition that causes turf to become hydrophobic (water repellent).

Once LDP has taken hold, irrigation simply causes the unaffected areas to get lusher while the LDP affected areas get drier. This exacerbates the problem making the green increasingly frustrating to play on.

Soil sampling will reveal powder dry soil. Unsightly brown patches of turf start to spread over most of the green. The turf on these areas recedes causing a bumpy surface and in most cases the weakened grass will be taken over by moss. But what can be done to cure the problem?

Research shows that fungi can contribute to the onset of this problem. Fungal mycelium may coat individual soil particles making it impossible for water to adhere to them.

Thatch control and irrigation management are the two most critical factors in the management of this problem.

By the time the problem is visually evident it is already too late to achieve an effective cure. This is because the problem is inherent in the green and usually only becomes visible at the height of the season.

dry patch
Infrared photo of green showing LDP

Irrigation management requires an understanding of Water Balance in the soil and this is detailed in Performance Bowling Greens. Just look at the infra-red thermographic image on the left, it shows an infrared image of a bowling green. The red areas show the extra heat that is being kicked out by the LDP affected areas, and that is directly related to the lack of moisture retained in the soil in these areas. In the standard photo, the LDP is barely noticeable at this stage, but will get steadily worse.

dry patch
…but there is still no real sign on the surface

Frequently we are now seeing that areas affected by dry patch disorders have suffered a complete depletion of moisture and that the soil structure has failed, turning to powder. Traditional wetting agents have sought to address dry patch from a very limited viewpoint, namely the reduction of water surface tension making it easier for water to be attracted and held around individual soil particles.

Although Wetting Agents can be used to good effect on LDP once dry patch has progressed to what we call breaking point, no amount of simple surfactant wetting agent will help it re-wet sufficiently to ensure a full recovery of the turf with full grass cover. Typically the manager has to wait for the turf to over-winter before full grass cover is returned.

This makes it all the more critical that we ensure that the products we use are effective in both results and cost.

As LDP is a disorder within the soil it is important to keep one eye on re-wetting and one on re-building the soil’s health. This can best be achieved by ensuring that you use a  wetting agent product which can supply carbohydrates to the soil in addition to their soil re-wetting properties. The addition of a high volume of Carbohydrates ensures that the products also contribute to the maintenance of soil structure while helping stressed grass plants hang on to life for longer while the soil is re-wetting.

Excessive use of sand on bowling greens over the years has been the single biggest influence on the occurrence of LDP.

More on the causes and management of LDP here.

The great top dressing hoax

Top dressing with high sand content composts has become a tradition in bowling green maintenance but it is far from beneficial.

  1. After 3 decades of routine top-dressing most greens are “inert” and can’t support a population of beneficial soil microbes.
  2. Soil microbes break down thatch and release nutrition to the turf.
  3. High sand and thick thatch usually result in Localised Dry Patch which is a long lasting, devastating condition that causes the soil to repel water.
  4. The surface smoothing and levelling actions of top-dressing are massively over-sold and of very little relevance to producing a smooth, fast green.
  5. Most bowling green irrigation systems are inadequate to start with, but are completely useless in the face of localised dry patch.

The process of top-dressing a bowling green has become so ingrained in our maintenance practices that it is hard to find a club that doesn’t do it, but over the decades it has devastated a huge number of greens in the UK.

Do your green and your wallet a favour and break the habit this year.

Performance bowls green properties.

How can we ensure a consistently high performance bowling green that is economical to produce and maintain. There are 4 specific goals that we need to achieve to say that we have such a green:

Green Speed; the actual surface pace that we can reasonably expect from the green on a regular basis.
Consistency; the ability of the green to replicate high performance throughout the day, week and season and also from season to season.
Predictability; the ability of the green and individual rinks to be set up for play of a reasonably predictable nature, time after time and over time.
Achievability; high performance must be not only physically achievable but also relatively easily achievable and for that the program we put in place must tick the following boxes; it must be:

Workable; with “in-house” labour and skills or with a financially sustainable amount of “bought in” labour and skills.
Sustainable in terms of its environmental, financial and infrastructural requirements.
Replicable time after time within the parameters defined above.
Minimum Input in terms of artificial fertilisers, chemicals and expensive bought in machinery or skills.

The goals we have set above require us to produce a very specific kind of green surface.

Act now on green dry patch

LDP, localised dry patch on bolwing green
spring is a critical time for LDP management

If your green has suffered the blight of localised dry patch (LDP), sometimes called bowling green dry patch in the past, this is the most critical time of the year to take action to minimise the chances of another outbreak.

It’s unlikely that you will be thinking about irrigation of the green just yet, but dry weather in March and April, usually accompanied by drying winds which cause further moisture loss from the green surface can allow LDP to take a firm grip on the green.

The main effects of this might not show up until June, but the damage will already be done and no amount of irrigation will correct this once it has taken hold.

With this in mind and especially if your green has suffered in the past, you should at minimum be keeping an eye on your water balance chart and making irrigation applications to replenish any deficiencies, even if it seems counter intuitive…trust your water balance sheet!

Now is also a good time to mini-tine the green and apply a granular wetting agent, making sure it is washed into the tine holes thoroughly.

Monthly liquid wetting agent applications should also commence now and the water balance sheet (not Charlie, the club champion in 1977, who doesn’t believe in watering greens!) should rule the roost as far as irrigation decisions are concerned.

Much more on LDP here.

The Circle of Decline—why many bowls greens never improve.

The diagram below shows the process that many poorly maintained bowling greens experience over a period of years if 3 basic maintenance issues are not addressed as a priority.

The top 3 issues on all fine turf are:

1. Thatch Control

2. Compaction Control

3. Turf Nutrition

the Circle of Decline, the reason many greens never improve

In addition to the top 3 there are of course other important issues such as irrigation management, topdressing etc, but if these 3 big issues are under-managed then the green will spiral into what I have called the Circle of Decline.

Simply put this is the course of events that go on largely un-noticed by many bowling clubs until it is too late to effect a quick recovery.

A lack of attention to thatch build up (see other posts under the thatch category) results in a thick mat of un-decomposed  dead grass shoots, roots and leaves. This mat gradually effects the turf’s ability to put down roots and take up water and nutrients. In advanced cases a root break will occur and Localised Dry Patch is a very common symptom of excessive thatch also (see other posts under the LDP category)

Disease

In winter, thatch can hold water like a sponge and encourage fungal diseases such as fusarium patch to take hold. This sometimes results in over use of chemical fungicides which kill off the disease and many beneficial fungi into the bargain.

Symbiosis

Grass relies on beneficial microbes, such as fungi to make best use of the available nutrition and so begins to have difficulty obtaining the necessary nutrition from the soil.

This often results in over fertilisation, as much of what is applied is not made available to the plants due to the anaerobic conditions which now prevail.

By now conditions are highly favourable to the weed annual meadow grass which is a very shallow rooting species. The finer fescue and bent grasses are compromised and in an effort to keep the meadow grass alive excessive irrigation is required.

This contributes even further to the excessive thatch layer as meadow grass is a prolific producer of thatch and we are back to the beginning of the cycle.

Action must be taken to break into the circle of decline, take action before its too late for your green.

Getting Bowls Green Irrigation Right

Bowls clubs are often divided on whether to water the green or not. When I visit clubs to advise on this, they are generally under-watering their greens.

This results in poor surfaces, especially when a green is still within the renovation phase as described in my book Performance Bowling Greens.

You can think of Soil Moisture Deficit in much the same way as a negative balance in your bank account.

Soil Water Balance Management…

…is almost unheard of within bowling circles or certainly the bowling circles I have been involved with but is a critical part of the management program to get right for high performance and deals with the management or Read more

Irrigation, how much is enough?

Irrigation, how much is enough?
irrigation management is critical but straight forward

Irrigation is on everyone’s mind at the moment, but how much is enough?

As a general rule greens lose approximately 3-4mm of moisture per dry day to evapo-transpiration, although this can vary with conditions; that’s approximately 25mm or 1 inch per week.

Again a very general rule is that many of the more popular automatic sprinkler systems will apply around 1mm of water for every 2 minutes of run time.

So again as a general rule to replace a week’s worth of losses you should be running the sprinklers for around 50 minutes in the week.

Now I will add a qualification or four to that:

  1. requirements can vary widely depending on location and conditions.
  2. don’t apply light applications on a nightly basis, try to group these into heavier and less frequent applications for best effect.
  3. try to move to a water balance sheet type system to manage irrigation more accurately…it will pay off quickly
  4. don’t rely on a typical bowling green irrigation system to apply water evenly or in sufficient volume…always check and measure what you are doing.

Irrigation management and water balance sheets in my book Performance Bowling Greens.

any questions please ask!