Gordon Gill gives us an insight to why it is important to carry out pre-season rolling.
What a chore, a boring and mind numbing experience, so why do we do it?
By the time you read this some of you may have already started your pre-season rolling; I have completed four passes to date, but many will not have even started as we are experiencing a very slow transfer from winter into spring.
Why do we do it?
Very simply, during the winter months the soil profile soaks up the winter rains and fills the pore spaces within the profile. As this happens the clay soil swells.
As we enter spring, are we there yet?
The grass growth picks up, the roots start to pull the moisture out of the profile. The days get longer, increasing soil and air temperatures driven by warmer sunshine help to dry the surface of the profile and pulls the moisture out of the profile, thus shrinking the clay profile leaving empty spaces, say like an Aero bar of chocolate. These spaces need to be closed down to create the solid block that we need to create the consistent pace and bounce that we desire to play our cricket on.
When to start?
Science has already informed us that the profile has to be drying and that we have to be experiencing drying weather. My way of checking whether the soil surface is drying is to push my thumb and finger tips into the soil.
If they come back wet and glistening then in my opinion the surface is to wet, you cannot compact water so no point in trying. My other rule of thumb, though the type of loam used may play apart here, is that I need at least a dry week before I even contemplate getting a roller out.
How do we do it?
Again the science report on rolling explains that we need to start with a light weight and during the rolling programme increase that weight quite quickly. I mow my square all winter using a 30 inch Hayter Senator, must be 25 + years old but I love it.
This is quite a heavy machine so I consider my light rolling done and I get straight out with the big roller just as soon as the ground conditions appear to be right.
If when rolling the roller is getting wet then I get off the square. If the roller shows the odd damp patch then I consider that to be fine, remember, you will need a small amount of moisture in the profile to act as an adhesive to actually stick those pore spaces together.
Now, how fast do we go and how many hours do we take?
You aim to travel at ½ a mile an hour, this equates to taking approx,one and three quarter minutes to get from one end of the pitch (wicket end) to the other. You roll in all directions, union jack style, I leave any rolling in the line of play until I am rolling my first pitch for play and actually prefer to roll on the diagonals.
Many groundsman still talk about how many hours they roll for, that's fine, but how many pitches do they have on their square?
Bound to take longer to roll a twenty pitch square than say a ten. Today we talk in passes, up and down the same line counts as two passes using a twin drum roller. Science again informs us that carried out in the right conditions 20 to 22 passes is sufficient.
So how long does it take?
Take a ten pitch square with ten foot wide pitches using a four foot wide roller; it will take three runs, to cover a pitch with the overlaps. With best will in the world it will be extremely difficult to get the exact speed correct so for ease of maths, let's assume each pass takes one and half minutes, I like to keep things simple though it may not read as so, let's assume it takes ten minutes to cover a pitch. So it should take approx 100 minutes to roll your square.
If you only have a three feet wide roller then it will take four runs to cover a pitch, so it will take three minutes longer per pitch. In this case it will take approx. 12 to 13 minutes per pitch making a total of say 120 minutes.
So a ten pitch square using a four foot wide roller and doing twenty passes will take approx 100 minutes per pitch, three and one third hours and sixteen and two third hours to roll the square. Job done, nowhere near the eighty to one hundred hours that we used to hear about.
To sum up.
A rolling programme is very important but it is not the be all and end all in achieving the required soil bulk density, a drying profile is. When carrying out the pre season rolling don't just roll every day because you can, unless the temperature is 20C plus, highly unlikely in this country. Leave two or three days in between each operation allowing the profile to dry so that there are some pore spaces to close down.
Remember, if the profile is too wet the roller cannot push down on the soil, it will only sink into the profile and push the soil forward. This will often create a break within the profile which will in turn absorb the force of the ball instead of rebounding it and is often the cause of slower, lower pitches.
So despite having good intentions we can easily do more harm than good. The perfect soil profile needs to be a lot drier than the average person thinks, but, too dry and there will not be enough moisture to stick the pore spaces together.
Remember this, to achieve the best there is no hurry, you will only achieve the optimum for your ground as the ground conditions become right whether that be during March or April or even May.
The fact that the fixture secretary or the league has arranged your first match is not going to change the weather. If a game has to be played in less than ideal conditions use your mower as the roller, it will be plenty heavy enough. A very apt saying is this, LESS IS OFTEN MORE.