Effects of season and frequency of harvest on browse yield and root carbohydrate reserves of willows (Salix spp.) in New Zealand

• Published in: New Zealand journal of agricultural research 2002-06, Vol.45 (2), p.87-95
• Main Authors: Oppong, S. K., Kemp, P. D., Douglas, G. B., Foote, A. G.
• Format: Article
• Language: English
• Subjects: alba; coppice; harvesting frequency; harvesting season; regrowth; Salix kinuyanagi; Salix matsudana; silvopastoral; willows
• ISSN: 0028-8233; 1175-8775
• DOI: 10.1080/00288233.2002.9513497

Provision of large amounts of browse of willows (Salix spp.) for livestock in dry summers requires the selection of suitable times for coppicing the trees. The effects of time and frequency of harvest on the edible and total dry matter yield and root carbohydrate reserves of Salix matsudana × alba and S. kinuyanagi were measured. Trees were harvested initially in winter (WSpSuA), spring (SpSuA), or summer (SuA), and then at 10-weekly intervals until autumn, except for the winter control (WA) harvested initially in winter and then again in autumn. The greatest cumulative edible and total dry matter (DM) yields were for S. kinuyanagi in the WA treatment. In the WSpSuA and SpSuA treatments, the DM yields of this species were 2-to 4-fold greater than for the SuA treatment. For S. matsudana × alba, yields of the WA, WSpSuA, and SpSuA treatments were similar and exceeded those of the SuA treatment by 4- to 6-fold. Root carbohydrate reserves in S. matsudana x alba comprised more than 90% sucrose and were highest in mid spring. Spring harvesting of Salix trees in coppice blocks will result in reasonable yields of accessible, edible DM for browsing by livestock in summer.