Scores and assessments come from experiments performed for the official registration of turf varieties under national regulations and according to rules approved by the French Ministry of Agriculture and Fisheries.

Scores from agronomic experiments are obtained during three years of inspection by the official network. They are influenced by climate and agronomic conditions in the trial years. They cannot ensure results that, for other years and conditions, will be or could be significantly different. All the scores together cannot guarantee a result. They depend on production conditions inherent to the living products and subject to climate hazards and specific or abnormal conditions.

All variety scores are re-calculated every year from their results obtained in the CTPS (Permanent Technical Committee for Plant Breeding) trials and compared with all reference controls. The value of controls is the result of trials and statistical estimations for years when they were not present. Some controls that have potentially been over- or under-estimated at registration can therefore be re-adjusted. The comparison of varieties not-tested in the same year is more accurate.