Nutritive value of leaf fodder from the main woody species in Iceland.
In the past, leaf fodder from woody species played an important role as animal feed in Iceland. However, very limited information exists on the nutritive value of the main woody species used as fodder. The aim of our study was therefore to determine forage quality of leaves of Betula nana, B. pubescens, Salix lanata, S. phylicifolia and Sorbus aucuparia and to compare it with forage quality of a common native grass, Deschampsia cespitosa, and with an introduced grass, Alopecurus pratensis, used by contemporary Icelandic farmers for forage production. In late June 2013, we collected samples of all species at four localities in Iceland and determined concentrations of nitrogen, phosphorus, neutral and acid-detergent fibre and lignin and compared them with the optimum range required for sheep nutrition. Nutritive value of leaves of woody species was relatively high and browsing of their leaves and collection of their leaf fodder for winter feeding could satisfy sheep/cattle nutritional requirements for N and P. However, the high content of indigestible lignin, present in all the woody species, functions as a barrier to nutrient digestibility. Grasses were characterized by lower P. The forage quality of leaves of woody species increased in the order B. nana < B. pubescens < S. phylicifolia < S. aucuparia < S. lanata.