Phenological development of meadows – 21 years of observations

In spring, the phenological development of meadows influences forage quality, particularly in terms of the digestibility of organic matter. Thus, phenological observations facilitate grassland management during first grass growth. Since vegetation development depends largely on meteorological conditions, long-term phenological monitoring also enables the effects of climate change on vegetation to be assessed. The aim of this study is (i) to update the method serving to establish the average phenological stage of a meadow by considering several species, and (ii) to study the changes in precocity of meadows occurring between 1995 and 2015. The results of this study show that the first grass growth occurs increasingly early in the lowlands (date of full heading occurs 2 to 3 days earlier every 10 years), and that there is more frequent alternation between very early and very late springs. These changes highlight the importance of following the phenological development of meadows as a whole, particularly using the method put forward in this article.