In order to investigate their potential contribution to ruminant diets, the nutritive value of the leaves of five tree species was evaluated across the seasons. The sampling campaign was conducted on a French network of agroforestry paddocks implemented 25 years ago located in the north, the centre and the south of France. Tree leaves were collected on ash (Fraxinus excelsior), service tree (Sorbus domestica), sycamore tree (Acer pseudoplatanus), walnut (Juglans × regia × nigra) and wild cherry (Prunus avium). The nutritive value of the collected leaves was evaluated in June, August and October 2016 by analysing their protein and fibre contents and in vitro digestibility. Tree leaves composition exhibited large variations between species and between seasons. From spring to autumn, average DM varied from 288 to 450 g kg -1 , fibre content from 383 to 338 g kg -1 m and crude protein content from 160 to 110 g kg -1 . On the contrary, in vitro digestibility remained quite constant across the seasons (from 67.7 to 66.9%). This result contrasts with what is observed on grasses and herbaceous legumes in which in vitro digestibility decreases in autumn.