Chapter 13: Willow

Willow is already recognised as a promising dedicated bioenergy crop in several countries. Of most importance is a capacity for rapid growth in several species, which is further promoted by cultivation as Short Rotation Coppice (SRC). Moreover, compared to some other bioenergy crops, yields are less reliant on the input of high levels of fertiliser, the production and use of which is costly in terms of greenhouse gas emissions. Willows, which are naturally adapted to a wide range of habitats, also offer promise in terms of production on subprime land, somewhat mitigating concerns over potential competition for land for both food and fuel crop production. Willow may also be the crop of choice at northerly latitudes where sufficient yields from other crops are difficult to obtain. While the wealth of diversity represented within the genus is yet to be fully exploited, breeding programmes have already made considerable progress in terms of yield improvement. Molecular underpinning work that aims to improve understanding of key traits and increase selection efficiency is also well underway. Although not yet comprehensive, early studies on the potential environmental impacts associated with increased SRC willow cultivation are encouraging.