Swelling, shrinkage and motties ... you could be forgiven for thinking you had stumbled onto the set of an X-rated movie.
But, it's all to do with the slightly less raunchy subject of cricket loams, their compatibilty and playability, a subject Nick Tebbs, Grounds Manager at Oundle School, knows a lot about after recently changing loams on all his squares.
In the latter part of last year, a message board poster complained of a batch of Kaloam that had been supplied full of stones, with photographic evidence to back up the accusation. Sadly for the postee, the loam had already been laid on the square and the ensuing threads confirmed that the problem was not confined to one batch, as other groundsmen had suffered similar issues with their supplies of Kaloam.
Fast forward a few months, and the suppliers, Monro Sports, are now in receivership, with the future of Kaloam secure, but its sister product, Ongar, uncertain. We understand that a buyer has been found for Ongar, but no firm details are available. As is the way with these things, supplies through 2011 may well be affected, although we are at the right end of the year for the matter of supply to be resolved before autumn renovations begin.
Both products have been hugely popular with cricket groundsmen over the years. Kaloam has predominantly been used on squares for junior cricket, with its stronghold being the Midlands, Gloucestershire and Somerset. Ongar is more widely used, with many of the county squares incorporating the product. Both are renowned for having a high clay content.
So, as well as the issue of stones in the square for this coming season - not good for cylinder mowers or batsmen - many groundsmen have been asking whether it is possible to change the make-up of their square and introduce a new loam.
So, with that question buzzing around my head, I contacted a few groundsmen to find out if anyone had carried out the process recently, and what were the methods involved. One name that kept being mentioned was Nick Tebbs, Grounds Manager at Oundle School near Peterborough, who had moved from Kaloam to Boughton County Loam.
At the end of February, I met Nick, and Head Groundsman, Stuart Palmer, to find out just what it entailed, and his reasons for undertaking the project.
Oundle School has four main squares, with other 'satellite' tracks within the school grounds. The main square has seventeen pitches, whilst the 2nd, 3rd and 4th team squares have eleven, nine and eight tracks respectively. They were all originally constructed with Kaloam and managed, for many years, using this loam for repairs and renovations.
Nick takes up the story.
"All the squares at the school had a reputation for poor performance, often described as being slow and low, and they also suffered from variable bounce. At the same time it had been difficult for grass to recover on the Kaloam soil."
"Many years ago, a decision was made, by the previous Head Groundsman, to relay six wickets with new Kaloam. They were excavated using a 360 digger which, unfortunately, heaved the soil as it was excavated, and this also resulted in a lack of control over achieving a consistent depth. The excavated wickets were refilled with the new Kaloam. As you can imagine, it was not a successful exercise, and further work was considered. But, it has to recognised that, at the time, current methods and advice were not available."
So, in 2003, two wickets on the main square were changed to Ongar, and a more considered approach was given to the work method.
The new pitches were excavated, using a Koro, to a depth of 4" and refilled with the new material, consolidating as they were refilled. "These new wickets tended to outperform the old Kaloam strips," says Nick, "but I wanted to carry out further trials to see if any other loam might suit our requirements even better."
"So, after much deliberation and some other trials using Boughton County Loam (motty and half motty tests were carried out on both loams), the results indicated to me that the County loam would suit the needs of the school."
"We took the decision to reconstruct a number of wickets over time - four a year - until they were all completed. We chose alternate wickets so that there was minimum impact on the use of the square the following seasons."
The wicket replacement method reflected a considered approach to achieving consistent depth. "After the use of a turf iron around the edge of the wicket to achieve a clean cut, a rotavator, set to a depth of 2", was used in two passes. The old loam was removed, making sure that the excavation remained an even depth, and taken away in small loads on trailers fitted with flotation tyres. Plywood boards protected adjacent wickets. The base of the excavations were spiked, and the first layer refilled with Boughton County Loam and then spiked again."
"This was to ameliorate the base layers of old loam with the new," says Nick, "so that there was no abrupt change in the soil profile. We continued filling, in no more that half inch depths, raking and consolidating, treading and healing as we went. A compact tractor, fitted with cleated tyres, was also used to aid this process. In the final stages, level boards on the edge of the work helped us screed off to a level surface, leaving it slightly proud to allow for sinkage."
Whilst wicket performance did improve, there were problems. "Some wickets were great," says Nick, "but most were still indifferent and, in some cases, awful! This was disappointing for everyone, not least the groundstaff."
Nick discussed the issues with Boughton's Simon Hedley. Visits were arranged and the squares inspected. Wicket preparation techniques were discussed and not found to be a problem but, because the wickets had been replaced at different times - a necessity to ensure the squares could still be played on - there were very slight variations in the levels. Simon suggested that these slight changes in levels can sometimes result in different moisture levels and playing characteristics within areas of the same wicket, so he recommended koroing off the whole square to reset levels.
In 2009, Nick enlisted the services of Total Turf Solutions and Boughton Turf Management to survey and re-level the whole 1st team square in one operation, using the Koro fraise mower.
"Re-levelling the square has made a huge difference and helped produce better wickets," says Nick. "All the squares now play very well, and there are no serious issues of cracking, dusting, inconsistent performance or slow germination. We are now receiving positive comments from the coaches and players, so it's not only good news for them but also for the groundstaff."
Instigating the change of loam has, in the end, proved very successful, "but, it is not something to be carried out without seriously considering all the factors and possible pitfalls," suggests Nick. "Remember, this has not been done overnight, it has taken us a number of years to get where we are today. Just changing a loam is one thing - getting some sound technical advice, carrying out your own tests and, of course, how you manage it, have been the key to success."