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turf grass

Turf grass leaf growth factors

Moving on from yesterday’s post which detailed the structure of grass plants, today I want to go into more detail about the processes and factors related to the growth of turf grass.

Leaf Growth
When we think of turf it’s easy to imagine that each individual blade of grass is a plant. However, each of the blades we see in the turf is a single leaf of a plant that might have many other leaves. All growth occurs from the base of the leaf so that the bit we cut off is always the oldest part of the living plant tissue and it is this feature that allows the grass to be mown frequently without undue injury. Although the main function of the leaf is to manufacture food for the plant through photosynthesis and increase the biomass of the plant the leaf can also take in water and nutrients to some degree.

Factors which affect leaf growth

Environment
As we observed in the post introducing warm and cold season grasses there are certain environmental factors that affect the growth of the turf grass leaf.

Temperature
Temperature is one of the most critical factors in leaf growth.

  • Cool season (C3) grasses have an optimum temperature range of 160 to 240C
  • Warm season grasses (C4) have an optimum range of 270 to 350 C

Sunlight
Sunlight is the main energy source in photosynthesis which the plant must do to produce food in the form of carbohydrates. In shade the density of turf will decline significantly which is a sign that there is much less biomass (plant tissue) being created by the plants.

Soil
For successful growth the plants need a favourible soil environment that allows for unhindered root growth. When rooting is curtailed so is leaf growth.

Cultural factors

Mowing height
When the grass is allowed to grow higher this results in more leaf tissue and therefore a greater leaf area for photosynthesis which in turn results in a greater production of carbohydrates for plant food.

Nutrition

  • Nitrogen (N) – an increase in available Nitrogen will typically result in increased leaf growth.
  • Iron (Fe) – the availability of Iron helps to ensure that the plant has the correct level of chlorophyll synthesis which is needed for the photosynthetic process to work efficiently.
  • Water – a very high percentage of plant tissue is water and this makes it critical to plant survival and healthy growth.
  • Diseases – the control or discouragement of disease pathogens is essential to strong and vigorous plant growth.

Next time we’ll look at some of the different growth habits you will encounter in turf grass management.

Meantime, why not share your views in the comments? or drop me a line.

Photo thanks to Kevin Dooley

 

Bowls Green Maintenance Basics – Surface Consistency

Have you ever played a great game of bowls when everything on the green was perfect; you read every twitch on the rink and it seemed like you had finally got the green the way you wanted it.

The disappointment when you return to the green the very next day, prepare the rink in completely the same way but get totally different and inferior results is maddening.

What went wrong? or maybe what went right?

Like green speed, there is much debate about surface consistency, both in terms of consistency across the green surface and consistency of playing conditions over the season.

In order of their impact on green surface consistency these are the top 7 factors that you should bear in mind. Obviously there are others such as weather patterns, level of play etc, but these are largely out of the greenkeepers control and in any case do not figure highly in the management of green consistency.

  1. Fertiliser Policy; yesterday we talked about the role that Bio-Liquid fertilisers can play in producing Performance Bowling Greens. The use of these products is recommended primarily in order to help in the improvement of the underlying soil; but this has a knock on benefit of smoothing out the peaks and troughs of fast and slow growth to a more steady and slow growth pattern. I’ve made this my number 1, issue in achieving green surface consistency.
  2. Irrigation Management; understanding the water requirements and in particular soil water balance is an important aspect of green management. The finer grasses we seek to encourage can root more deeply than the weed annual meadow grass and as such our watering policy should be deeply, not daily.
  3. Localised Dry Patch Management; the scourge of many greens over the last 2 decades due, primarily to the overuse of sand top-dressings and the neglect of the soil/plant relationship. Localised Dry Patch is a condition (not a disease) that causes the soil to become hydrophobic (water repellent) and can cause major disruption to the surface levels. Localised Dry Patch is also a season long problem in most cases regardless of how much rain or irrigation there is; once it takes hold it is usually very difficult to overcome.
  4. Mowing Frequency; we looked at this issue in more depth last week. Mowing frequency is at least 100 times more relevant to green consistency than mowing height. Shaving the green down to 3mm is damaging to the grass plants and counterproductive in producing a performance green in the longer term. If we truly want a consistent green, we need to make some hard decisions on how we are going to manage the workload.
  5. Thatch Layer Control and Management; closely related to, and the catalyst for most other green maintenance problems, thatch is only a problem on intensively managed turf such as bowling greens. One of the most commonly discussed topic on this site.
  6. Compaction Control and Relief; one of the major catalysts for the build up of excessive thatch is the process of compaction of the soil. This causes the soil to become lacking aeration pore space and oxygen as a result.
  7. Sward Composition (grass types); a low priority on this list but none the less important in respect of the overall aim of the Performance Green Program. By doing the work required to encourage a tight sward of finer grasses we automatically do the things that encourage a healthy living soil and that is the key to a performance bowling green.

Bowls Green Maintenance Basics-Thatch

Where grass grows on soil of any type the health of the turf/soil eco-system can be assessed by looking at the thatch layer.

On grass areas where there is little or no human interference in the form of excessive compaction, fertiliser, pesticides and mechanical work (other than mowing) such as in meadows or parks  the thatch layer will almost always be at the optimum level for a continued healthy turf/soil eco-system. This is due to the soil/plant relationship being in balance; a strong and sufficiently lively soil microbe population releases nutrition from the thatch layer as it decomposes naturally.

As we move to areas that are subjected to progressively higher maintenance and wear activity, the thatch layer is susceptible to becoming thicker and denser and therefore needs more intensive management if the turf/soil relationship is to be kept in balance.

This can be observed by taking samples from a variety of grassed areas and comparing them to your bowling green’s thatch layer; rough meadows and areas such as the roughs on golf courses being the most natural and healthy areas and greens usually being the least healthy and in need of the most remedial work to keep them right.

When turf is used for bowling or other activities, the soil becomes compacted which is literally the expulsion of air from the soil. This throws the natural balance in the turf/soil relationship and makes it necessary for us to intervene to correct things.It is important to remember that thatch is always being produced and the more vigorous and intensively used and managed the turf is the faster it produces thatch. The desireable fine bent grasses and the common weed-grass, annual meadowgrass are prolific thatch producers.

If we don’t do the right things to correct this effect or indeed if we don’t do them often enough the green can very quickly fall into the circle of decline we looked at in an earlier article.

Top Dressing Bowling Green

(s)Top Dressing!

Recent summers have seen a lot of greens devastated by Localised Dry Patch a disorder that is rapidly becoming the scourge of Bowling Green Maintenance Specialists and Club Greenkeepers a like.

I make no apology for writing about this once again, because in my opinion this issue has the ability to accelerate the decline of many already shaky clubs.

It is also clear that there is a deep misunderstanding of the issue across the bowling community…how do I know this?

Well, on several occasions over the last week I have been confronted with some of the worst examples of Localised Dry Patch I have seen in 30 years; in some cases there is virtually no grass cover left and the green surfaces are unlikely to hold together until the end of the season, but…

Despite that, I am still coming up against two of the most mind boggling situations time after time:

  1. The first is when I am actually demonstrating Localised Dry Patch in action by removing soil samples from affected greens and showing committee members powder dry soil/sand; and they insist that they think the green needs a good top-dressing!
  2. The second is when I get a phone call or email from a club with the same severe LDP problems who have had a recommendation from an “expert” that they need to top-dress their green to over come the problem.

Listen folks; I know this is turning into a bit of a rant but here are a few bullet points that you must remember if your green and maybe even your club is going to survive:

  1. Localised Dry Patch (LDP) is a soil disorder not a disease so it can’t be reversed over-night by any quick fix method regardless of how convincing the salesman is!
  2. LDP has the capability to ruin your green beyond economical repair.
  3. LDP  is so common because clubs have habitually thrown tonnes of sand based top-dressings at their greens for decades; the tipping point has been reached, many clubs are now trying to produce bowling surfaces with limited budgets on very high sand content soils; it can’t be done!
  4. More sand will only make the problems worse not better.

So what can be done?

Well currently if your green is affected even mildly by LDP and you are in the process of thinking about an autumn program that includes top-dressing with several tonnes of high sand content top-dressing you are not only damaging your green, but you are also wasting hundreds of pounds.

  1. My eBook Performance Bowling Greens, a practical guide costs less than a bag of fertiliser, so do your green a favour and just buy a copy…its peanuts compared to what you are about to do otherwise.
  2. In the book there is a clear plan for getting over LDP and moving your green to a consistently high performance surface.
  3. You will save a lot of cash by taking a more natural, less abusive approach to green maintenance.
  4. The savings you make could be what saves your club from going under and your green will be on the road to recovery and consistent high performance into the bargain.

If you decide to ignore this, then please take away one message “Stop Dressing”

Performance Bowling Greens

Should a new bowls green sink?

There aren’t many new bowling greens being built these days but of those that are appearing the initial euphoric rush of the members is somewhat dampened when things seem to immediately start going wrong with their shiny new green.

One of the most common occurrences is that the green sinks, causing bumps and kinks on the surface. I’ve witnessed this first hand, usually after drawing up a specification for the construction of the green and then returning to find that the project architect (bowling green construction is quite often just a part of a bigger project involving buildings etc) and/or contractor has “interpreted” or worse “adapted” the construction specification, has adapted the construction program (sequence), has adopted non-approved methods, or has used “alternative” materials.

In reality it’s usually a mixture of all of these and the main reason that this happens is to save money on the overall project and this usually happens because the project has run over budget on one of the other elements such as the clubhouse or car park. So the most important part of the project suffers due to a lack of good management of the project overall.

Typical details of this are:

  • Purpose built, pre-cast concrete edge/bank sections replaced with wooden batons and concrete blocks to save money.
  • Rootzone depth adjusted to save on materials.
  • Rootzone laid in one layer instead of being built up and consolidated after each layer.
  • Cheaper spec gravel used for drainage layer and trench backfill.
  • Wooden batons, blocks, tools, sandwich and drink containers, grease cartridges, drainage pipe off-cuts etc being left in the green after construction is complete.

Now, if your new green has started to sink and is causing difficulty for your club, your architect, again, should have retained a percentage of the project total from the main contractor until a maintenance period has elapsed (usually 12 months) and any snagging lists are completed to your satisfaction; this allows time to pass for mistakes to start to show up.

In addition to this, there should also be a warranty period on the construction and it isn’t unreasonable for this to be 5 years on workmanship and materials.

Finally, there is the fact that despite all of the above being dealt with properly and on time, the very nature of a bowling green is that it will start to settle out in various places, but this should be minimal and will require some level of corrective maintenance to put it right and this is the main reason for the 12 month maintenance period being included in contracts of this nature.