Local Dry Patch - LDP
LDP creates dead, dried out patches on a croquet lawn surrounded by perfectly green areas. So the lawns develops very fast patches of dead grass which makes some croquet shots a pure lottery. If there are small local dry patches it can cause the earth to contract and become bumpy. The result is that accurate shots become unintentional jump shots and can result in the loss of a game. So it can be very very annoying for players.
It can be treated by the application of a special curative. But unless you catch it at the very early stages it can take weeks for the grass to grow back especially mid season and it may not fully recover during the season. So where Dry Patch is a recurring problem a preventative programme of treatment needs to be employed.
What is LDP?
Under certain conditions soil can become water repellent resulting in changes to hydrological behaviour, nutrient uptake and plant growth.
Soil water repellency has been recognized in most parts of the world and has been observed in all soil types from sand to clay. Although water repellency in soil has several possible origins, numerous researchers agree that it is caused by an organic coating on the soil particles.
When does it occur?
Water repellency is influenced by season and soil water content. In most cases, repellency decreases during wet autumn and winter months and is most severe during dry periods in spring and summer. Research has shown that patches of soil can become water repellent to a depth of up to 16.5 cm thus forming blocks of repellent soil which are surrounded by normal wettable soil. Rain and irrigation are not absorbed through the surface of a dry patch or from the water table below.
How can it be prevented?
Slitting or tining doesn't cure water repellency and, in my experience, most wetting agents don't do the trick either. In 2004 research was carried out at the “De Pan” golf course n the Netherlands where Aquatrols Revolution surfactant (surface active agent) was tested over a two year period. One half of a fairway was treated monthly and the other half left untreated. Core samples 25 cm deep were taken monthly at 25 cm intervals over 25 metres. The results are shown in the two graphs. The first shows the water content levels across the untreated and treated halves of the fairway. The troughs are the dry patches and the peaks have high water content and are normal wettable soil as confirmed in the bar chart.
By using Aquatrols Aqueduct and Revolution in combination LDP can be prevented. This has been used since 2016 by croquet clubs with 100% success.