21 Feb 2008 by EDS
I like to understand the reasons why we do what we do so....
Why in pre season rolling is proper consolidation only achieved by first using lighter rollers then heavier ones, rather than a heavy one from the start (assuming you could get on the ground with one)?
and whilst on the rolling .....
If you take a core sample what am I looking for in the sample? Having not taken one before is it quite simply that the soil has become consolidated?
Still Learning
Due to time factor
I use a 3.5 tonne Avelling Barford Roller right from the start of the rolling programme.
Have read somewhere it does not make that much difference.
If anything at times my square plays a little lower than I would like but I feel this is due to other factors.
All I know is that at the end of the season our square is very firm.
gmet233
21 Feb 2008 by zoid
Des
The ECB/Cranfield have spent the last three years trying to figure out how rolling works.
I spoke to one of their lead researches not long ago and he was pretty clear that the variables involved were far to complex to enable stock advice to be given.
If you get good results from hitting it with the heavy, go ahead and enjoy.
My own take is that ground conditions are far more important than the weight of roller used.
21 Feb 2008 by Mal
I'm with the view that if the ground is not right to recieve a roller then damage can be done. gmet, Using a heavy roller and if you are saying that you get a lower bounce I can only assume that you are getting root breaks from rolling when you do not have even moisture in the profile. May be worth you investigating as a hard wicket will still produce a low bounce in this situation.
Have a look at these Des:-
http://www.pitchcare.com/magazine/article.php?id=1585
http://www.pitchcare.com/magazine/article/3968
There is a wealth of knowledge on the subject of rolling, far more than can be given in a single thread. Just type in cricket rolling and you will be given plenty of reading material.
Geography is everywhere
I know a few people who say the go straight on with the big roller. But when they examine exactly what the do, they actually start with a mower. The act of cutting the square will also firm the surface with a rolling action. Just cos you're cutting doesn't mean it can't be thought of as part of your preseason rolling.
Of course there's no bounce, bend your back and put some bloody effort in.
Des,
I think you ask a very good question about weight profiling.
Using progressively heavier rollers will help in some circumstances. For example, if your square is prone to being squishy in spring, then putting a heavy roller on straight away will probably cause damage - particularly at roller ends.
I used to have only a heavy Aveling Barford with narrow rear rolls. On the first few times each season that I put this across the square I would have some places where the ground was compressed by 5 - 10mm by the roller. This must cause vertical root break planes. Towards the end of the season the cracks on the wicket could often be seen to be in straight lines running up and down the wicket, about a rear roll width apart. I'm convinced this was down to too heavy a roller in the early season.
I've now got a shiny new Poweroll which I can gradually increase the weight of. I'll see whether it makes any difference later in the year.
The ciderman rolls
Des,
I believe the key to any succesful rolling is in identyfying the right roller for the right conditions.
if you were to use a heavy roller on wet / saturated clay soils, you will destroy the soil profile, it will push out any air that is between the wet / cold clay particles out from the loam, making grass growth / establishment general health difficult to achieve. and causing a whole manner of other problems that Mal has mentioned.
This may result in poor performance.
By using a lighter roller first, you are only drawing out moisture from the top of the soil profile,. as the ground dries during the spring / rolling regime, this pulls the moisture from further down the profile to the surface, resulting ( hopefully) in 1 solid " lump" of clay loam, if you can achieve this then you can use the heavy roller to fully consolidate toward the start of the season.
This makes pitch preparation a bit easier in some respects, but more difficult in others, easier as the ground has been well consolidated during optimum rolling conditions, but more difficult because you wll need to thouroughly irrigate your pitch to ensure a good depth of moisture during pitch prep.
Covers will help in the irrigation process, if you dont have them, irrigate during periods of low evaporation ( early morning / late evening)
22 Feb 2008 by MCC
As some of us don't have the luxury of more than one roller, or one with an adjustable weight, we rely on the mower as our first roll(s) followed by the roller. It seems to work ok for us, the bounce is pretty consistent.
Des, do you roll with a cider in hand? We put a drinks holder on ours!
MCC
What you do is fine, using a cylinder mower as a light weight roller is done by many clubs.
In an ideal world, you would have something like 24" + 36" mowers then a weight adjustable roller, though there are many people who use different mower width variations, all to good effect.
Neil, I'd emphasize that a bit further. A cylinder mower is used by ALL clubs as an initial light roller - even if you're just cutting the square then you're having a rolling effect.
Of course there's no bounce, bend your back and put some bloody effort in.
22 Feb 2008 by k-hib
hi jon taylor glad to hear you have posh new roller ! does that mean youve put up rob sladens subs????? [hope so ha! ha!] see you soon karl @ boston
once a ransomes man allways a ransomes man !!!!
Karl,
No, we haven't increased Rob's subs. He bats for such a short time it's cruel to charge him a fiver anyway!
We got it off all those losing lottery tickets!
The ciderman rolls
23 Feb 2008 by EDS
Guys
Thanks all for your helpful comments - its not that I question using the lighter rollers first I just like to know why I'm doing it !!
Still Learning
Des, I was told that starting with a light roller gives the consolidation at depth - ie that the light roller consolidated deep down and not at the surface. This never made sense to me.
This is what I think happens:
NOTE, this is my conjecture and not based on me having researched any facts.
The main reason you start with a light roller is simply because there is too much moisture in the profile for it to be able to support the weight of a heavy roller.
As Neil said, the light roller induces a drying effect. The light roller consolidates the top of the profile - bringing the water to the surface where it evaporates. Water then moves from deeper in the profile into the upper profile via capillary action (?) and via the plant roots. Thus the deeper profile appears consolidated by the light roller.
As water is removed from the profile it gets to a point where it can support the weight of the heavy roller.
So you simply use a light roller because the surface isn't in a condition to support the heavy roller.
Compaction vs Consolidation:
For ages I've wondered what the difference is - I found this explanation on a website somewhere:
Compaction involves the reduction of volume through the removal of air voids, and consolidation is the reduction of volume through the dissipation of pore pressure in saturated soils by the removal of water.
Of course there's no bounce, bend your back and put some bloody effort in.
So JL,
Does that theory mean then, we consolidate while drying the wicket out, and then compact becuase we close up the air voids that the water has left behind. ?
I sense that this one might run and run !!
23 Feb 2008 by mario Last edited 23 Feb 2008
I sincerely hope not Gordon. My brain hurts already!
or was it the gin last night?
I know no boundaries.
23 Feb 2008 by jlawrence Last edited 23 Feb 2008
Now that is a good Q bath.
Water doesn't compress, air does. So when we're preping tracks, we are filling the air gaps with water (assuming you flood up the track). Rolling then squeezes the water from the upper profile and the water is drawn up from deeper. I don't believe that as water is drawn up air is drawn down to replace it - or not in considerable amounts. So we effectively consolidate the lower surface as the water is drawn upwards - without even having a roller on it :). Any air voids that we compress would I think be compaction - compaction because the actual amount of air hasn't changed it's just been squeezed into a smaller area. I think that the use of water means that we have less and less air that can be compacted - so flooding up more than once should result in less and less air in the surface and therefore more consolidation.
To say that cricket tracks are only consolidated would I think be false - if you don't flood up the track then you are compressing the air voids therefore compacting.
ADDED:
Interesting question. If you dry out a track without rolling at all, would the Bulk Density increase ? ie the track gets some consolidation just because it dries out.
Of course there's no bounce, bend your back and put some bloody effort in.
23 Feb 2008 by zoid
jl
Surely we water tracks to lubricate the profile not saturate it?
23 Feb 2008 by jlawrence Last edited 23 Feb 2008
dunno zoid - what is lubricating the profile ?
I think we flood the track to fill the air voids with water - forcing as much of the air out of the profile as possible. Then we roll to move the water around in the profile until it gets to the surface and can evaporate, resulting in a more consolidated profile.
Of course, I could be way off the mark with this.
Of course there's no bounce, bend your back and put some bloody effort in.
23 Feb 2008 by zoid
I work from the old adage that you can't roll water. Water is intended to provide lubrication to assist in consolidation.
I quote from the interesting article on this site by
By Colin Ashman in conjunction with Bob Scott (British Seed Houses)
Soil moisture levels can be classed as either extremely wet, extremely dry or somewhere in between, the middle point being field capacity. Soil strength is similar as it also has two extremes - elastic (hard) and plastic (soft). The middle point of soil strength is also at field capacity and at this point there are an equal number of pore spaces filled with water as there are filled with air (air-filled porosity).
The significance of field capacity on soil strength is that the greatest amount of consolidation can only take place when there's sufficient lubricant (water) and soil pores (air spaces) within the soil. As the moisture level moves from field capacity to wilting point, so the efficiency of consolidation is gradually diminished. To compensate for this, a heavier roller can be employed to increase efficiency and therefore its effects.
I agree zoid, you can't roll water. What rolling does is move water around within the profile. Some reaches the surface and evaporates.
I'd suggest that water is 'required' in order to achieve consolidation - not just to assist. Without water you don't have any consolidation you'd have compaction.
I have a feeling that by the end of this I'm going to have a headache - then Colin will start explaining at the next IOG meeting and I'll get an even worse headache LOL.
Of course there's no bounce, bend your back and put some bloody effort in.
Havent got a clue about any of this,
but,
the soil profile suffers the greatest amount of compaction when it is at "field capacity"
This is taught at a basic horticultural level with regard to soil science.
Field capacity is the point in soil moisture when all excess water has drained from the profile through gravitation and the remaining moisture is held by surface tension and capillary action.
By rolling the soil profile when in this state you will compact/consolidate? until moisture rises to the surface, at this point stop rolling, after the area has dried, roll again until moisture again rises to the surface, this will take longer each time as water is less available and is drawn from deeper down, as water is drawn from deeper down each time consolidation is achieved at deeper and deeper levels.
Initial roling with a light roller will allow limited compaction at an early stage without causing root damage whilst the soil profile is soft or damp.
p.s. without water the ground would be so hard you would be wasting your time and effort
Regards
Steve
Don't talk to me about Contractors Wonka, I am one myself......
23 Feb 2008 by Anthony Asquith Last edited 23 Feb 2008
Physical pressure on the surface by actual rolling doesn't greatly consolidate the Wicket but instead initiates a drying phase in the soil which sets up a matric potential difference beetween the soil surface and deeper horizons which dries the Wicket more comprehensive. As rolling is carried out pore space is removed and more small pores are created and it is this internal strength or cohesion which enables clay soils to be Elastic as the soil dries.
Soils with higher amount of Clay (especialy montmorilonite minerals) need LESS rolling as most pores are in the residual class rather than transmittance or capillary mesopores class so it's difficult to remove much more pore space, So why Roll.
Deeper layers are more affected by the rolling pressure once the surface dries, Shrinks and Hardens.
The load bearing capeabilities are increased as the soil dries in the upper layers and it's at this time a heavier force can be used ie heavier weight as the soil is stronger then the force applied to it.
Moisture is essential for clays to be moulded and Manipulated and the stage of Field Capacity is when MAX results can occur by even a small amount of pressure as there is sufficient moisture in the soil for lubrication and Air filled pore space to be able to remove more space and restructure itself to increase Density.
Humidity, Temperature, BD, OM and Shear strength..Mohr's circle and all that stuff is important.
Cheers
23 Feb 2008 by vid Last edited 23 Feb 2008
Ok AA, if thats the case what constitutes too much rolling and why, as this is critical. My practical knowledge of rolling has changed more regularly over the last few years because of the better information available now. Rolling has to be progressive - as the surface clays dry the roller forms a smaller footprint and therefore the downward pressure per sq inch increases facilitating consolidation at a progressively greater depth to achieve the desired 'bounce'. So I have a gap in my knowledge as to at what point a clay becomes over-rolled and what has happened to cause it
Over rolling is just rolling for the sake of it, no benefit, no gain, no improvement to wicket.
Rolling when the conditions are conducive gives greater benefits, as with ALL tasks carried out, TIMING is everything.
A.A. is that what I said(ish)?
Regards
Steve
Don't talk to me about Contractors Wonka, I am one myself......
23 Feb 2008 by zoid
10 minutes till I watch El Nino's magnificent hat-trick again!
Steve
I think vid (though I wouldn't want to put words or anything else in his mouth) is wondering what the physical damage is to dry rolling.
If it is just about waste of time, that wouldn't be be the end of the world. What I'm wondering is, does it actually do damage and if so why?
I've got this image of a Jacobs cream cracker, sitting on concrete with my autoroller passing over it. I have lots of other images involving lubrication but that's not important right now.
23 Feb 2008 by vid
Actually what I'm after is what damage is done to the damp profile, when over rolled. Wasting time and energy aside is the extra rolling of the moist profile damaging the structure and therefore downgrading the playing characteristics.
24 Feb 2008 by Anthony Asquith Last edited 24 Feb 2008
Clay Soils can only be manipulated to a certain degree even when moisture is present as there comes a time when the compressive limit of the soil is reached during any one session or phase of rolling untill the soil dries, shrinks, becomes more dense and hardens. In all cases any more than 4-6 passes during any one Rolling session is negligable in terms of it's effects on the soil. Any more is just wasted effott during any one session hence why small phases of Rolling on a "little and often" basis which allows drying in beetween is better than one long session.
Clay particles can only be manipulated so much untill drying and shrinking occurs and the drying phase initiated by Rolling causes drying at the surface and deeper in the soil. Much more harm is done Rolling when Wickets are too dry rather than over rolling when the soil is highly plastic and moist as you can only compact a clay soil so much under adequate moisture conditions and poor drying conditions.
Solid particles with very little "give" will break or crumble under added pressure but i guess you knew that already. Clays with enough water in interlattice and layers to be manipulated will tend to twist, bend etc to compensate, Especialy ones that can be fully hydrated - Montmorolinite for example varies in plasticity to the degree of hydration it exhibits as the swell process is carried out in several stages.
Overall smectite minerals produce the best Wickets due to it's swell capacity, Degree of hydration, High Cohesion, Elasticity etc etc.
Moisture is absorbed by clays via skins and in the stern and gouy layers but can exhibit small changes in volume due to small Humidity changes.
I know this isn't the specific answer you was looking for but hey.
Cheers
A little excess rolling when there is enough moisture present isn't (I think) going to cause great problems. Lots of excessive rolling might.
I know many of us are badgered to roll, roll and roll some more by some members in our clubs.
What you can do is get your surface close to the maximum bulk density it's capable of, then do your rolling sessions, then invite the moaner to sit on the roller for a couple of hours.
Take samples before, after your session and after theirs. Calculate the bulk density of the samples.
You should find that their session had less of an effect on the surface compared to yours. If you're lucky you'll find that their session lowered the bulk density - this should (I think) only happen if your at or close to the max - in which case you shouldn't have any great problem shutting them up for a considerable length of time :).
Of course there's no bounce, bend your back and put some bloody effort in.
24 Feb 2008 by mario
I think that we have all seen during a match before the commencement of the second or subsequent innings the captain of the batting side asking for the heavy roller to go on for the maximum seven minutes.
With this being done on a dry surface the concept is that the rolling effect "deadens" the surface for half a dozen overs or so.
My question is - Given all that has been discussed on this thread, what is going on if indeed the surface does deaden for a short period of time?
Or is this a myth which needs to be busted?!
I know no boundaries.
Good Q Mario.
In my experience as a player, putting the heavy roller on at half time does indeed deaden the surface for a period of time.
Why?
My thoughts are that it draws 'some' moisture up towards the surface, which then evaporates. This is the only reason i can think as to why the effect only lasts about 30 minutes or so, and the effect must (i think) be dependent on the amount of moisture left in the profile.
Of course there's no bounce, bend your back and put some bloody effort in.
24 Feb 2008 by vid
Thanks AA, its how I thought it was - too much rolling - wasted effort. I was just concerned that excessive rolling of the plastic surface would physically damage the cohesion between clay particles and result in a reduction of consolidation. I guess I shall have to wait for someone to do that bit of research, but from my experience those people who do 15 hours of rolling in one hit on very plastic ground with a very heavy roller (exaggerated) seem to end up with a low inconsistent bounce and a tendancy for the surface to turn to dust more readily. This would seem to suggest that something else is happening at particular level that is causing the bonds between them to break down
24 Feb 2008 by mario Last edited 24 Feb 2008
In a partial answer to my own question Jon, i concur that on a dry pitch use of the heavy roller between innings does indeed deaden the pitch for a short period of time.
However, in my opinion, it's not because it brings up a bit of moisture.
If this was the case, would the ball not have a tendency to seam?
My observations are that the ball, especially the new ball, doesn't come through quite as sharply therefore giving the batsman a short time to become accustomed to the pitch/bowlers/general conditions before the effect wears off.
Remember, this phenomenon, if this is what it is, will only work on a dry pitch.
I know no boundaries.
Mario, On a pitch that hasn't been dried fully, I've seen very odd effects by rolling at half time. Things like the track going dead for extended periods (like 30+ overs) and/or as you suggested the ball seaming all over the place.
Of course there's no bounce, bend your back and put some bloody effort in.
Never liked the heavy roller at the interval especially if we were batting second, light roller and a good brush and tidy up. Bounce remains good coming onto the bat, wicket doesn't seem to does as much for opposition spinners, even in really dry summers the heavy roller brings up some moisture.
A Freudian slip is when you say one thing but mean your mother
24 Feb 2008 by mario
We had a match here a couple of years ago. The pitch, square and surrounds had been under covers on the Thursday and Friday with them only being removed 2 hours ahead of the allotted start time.
We lost the toss, were put in and got about 230 for 8 off the 50 overs.
At half time the oppostion captain asked for the heavy roller. Remembering that the pitch was likely to have some moisture just below the surface I ensured that it was the heavy that he wanted.
To cut a long story short, they were dismissed for 78 with the ball seaming all over the place.
In the bar afterwards I asked the captain why he had chosen the heavy roller rather than a brush-up and the light one given the conditions in the preceeding days.
Oh, he said, "They always put the heavy on when I'm watching the televised games"!
Oh well...........not a lot to be said really!
I know no boundaries.
LoL. And his players were as good as those that he see's on the telly weren't they.
People watch how they do things on tv and forget that they're playing at a different skill levelto their own teams. Most teams i've seen would be lost on a 'tv' standard (ie county) track, it would likely have too much pace and bounce for them to be able to bat on.
Of course there's no bounce, bend your back and put some bloody effort in.
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