Hi and welcome to this months blog in this month edition we look at scarification with the help of Andy Mackay.
Andy is one of the most highly respected Head Groundsman (Sussex CCC)in the business and he will be sharing his do and don’t on scarification prior to renovations .
Andy Mackay in the below picture ,during a training day on behalf of the Sussex Association of Cricket Groundsman,where Andy is a pitch advisor.
What is Thatch?
•Thatch accumulates when the production of organic matter is faster than the rate at which it decomposes.
•Thatch is a tight intermingled layer of living and (mainly) dead stems, leaves and roots that accumulate between the layer actively growing grass and then soil underneath.
•Some grasses cause more thatch than others, annual meadow grass (Poa annua) is usually the number one culprit in cricket.
•Unfortunately on a square there is a conflict between the needs of the of the game and good turf management since the heavy, compacted soil does not encourage thatch decomposition.
Why is thatch a problem on a cricket square?
Thatch is the number one contributor to slow and low wickets up and down the country. However, it is easy to control if the right techniques are applied.
•Deadens /reduces bounce and pace.
•Soft and spongy surface, which the ball can tear.
•Thatch can hold water, meaning more chance of cancellation of games, an artificially wet surface and greater chance of moss invasion.
•It promotes weed grass such as Annual Meadow Grass.
•Turf is more prone to pest invasion such as leatherjackets and also disease.
Whilst some thatch may be desirable in other sports, there should be no thatch on a cricket square.
How do we know if we have thatch present and how much thatch is acceptable on a cricket square ?
•There are various ways of checking such as the use of corers but if you have a knife take a triangle section of turf from the edge of a wicket (not on the ends) and measure the thatch later with a ruler.
•Any thatch on a cricket square needs to be mechanically removed ,and is undesirable.
Picture above ,assessing the depth of thatch with the use of a knife or purpose made mini soil profiler.
What is scarification and when is this to be done ?
•Scarification is a process best described as a mechanical raking and is usually only carried out during end of season renovations .
•A scarifier uses a series of sharp blades that rotate at high speed and cut into the turf in a vertical motion.
Whats the difference between scarification and verticutting ?
•Scarification blades are thicker and stronger 2/3mm width and impacts the soil surface .
•Verticutting is an in-season operation using much thinner, closer centred blades that is used to thin out / stand up the grass prior to mowing and does not impact the soil surface .Verticutting, if done regularly will create a thicker more upright grass cover with less room for weeds,moss and weed grasses.
Below picture,scarification blades ,from a Hove’s tractor mounted scarifier(pic top of screen)
How to Scarify?
•Prior to Scarification, verticutting of any wickets which are thickly grassed can help the process.
•Never scarify at right angles to the last pass, as this can pull blocks up and severely disrupt the surface. As a rule of thumb, always work within an imaginary acute angle.
•Work to below the identified thatch layer .
•If no thatch is present then scarification will still need to take place to remove any dead grass in the top of the surface as well as prune roots and remove weak plants. As a rough guide 3 direction as a minimum: first pass or two at a shallow depth of 2 to 3mm and the last direction or two at a deeper depth of around 5-10mm to create a channel for seed.
•….Although never proscribe a set number of passes ,3 may be enough ,7 may not be .
•Brush /clean up between passes and reduce the height of cut to 4 to 5 mm prior to topdressing, aiming to leave a clean surface so that unwanted organic matter is not buried by topdressing.
•If your scarifier doesn’t collect then you can use a Mechanical brush ,leaf blower or even mow the debris up.
What machine is suitable for end of season scarification?
• The machines working capabilities are based on power and soil moisture ,the machine prefers some moisture in the profile. So a day or two before scarification get the square cut down to 3/5 mm and give it a good soaking, it will make for a less dusty job and take the strain off the scarifier.
•The deeper the thatch the more powerful the machine is required. Heavy duty machines such as Sisis 600HD and the Graden(doesn’t collect) make the process much quicker and are capable of penetrating deeper into the soil. Lighter duty machines such as the old Sisis rotarake Marks 3 and 4 may struggle to get very deep in the soil and will need using at much slower speeds and in damper conditions where deeper scarification is required.
Sussex Association of Cricket Groundsman scarifier training, in the below picture.
What are the options regarding the hire ,loan of a scarifier?
•Most County Association of Cricket Groundsman have machines for use at much below hire cost prices ,speak to your cricket board or pitch advisor.•
•Contractors will scarify for you ,if time and experience isn’t on your side .
•Purchasing your own machine, which is the best option since you can use it when you want and take as long as you need to to scarify, but having a verticut reel and perhaps also a brush reel as well as a scarifying reel will mean that the machine is used year round rather than only once a year.
•Hire from a reputable company .
How to prevent thatch ?
Don’t over water !
Don’t overfeed !
Do try to reduce Annual Meadow grass!
Focus on preventing thatch accumulation by regular (bi-weekly) verticutting!
Do mow regularly and box off!
Do brush up wickets after game ,by hand and a machine with a brush attachment ,if you have one.
Do seed with Perennial Ryegrass !
Remember be BOLD,you can kill a square with kindness(especially by not scarifying effectively)DO NOT RUSH! This is a crucial time of year and the quality of work will dictate the quality of the playing surfaces for the following season. If it takes several days to achieve a quality finish then be prepared to put the hours in.
If you want more specific insights on renovations ,click on the above link, to take you to a relevant article.
I hope this Months blog has been helpful ,please leave any comments below and think about subscribing to receiving this blog via email (free).
👀next month we look at aftercare of the newly sown grass.
Thanks to Pitchcare.com for sharing this blog.