Title: Effects of woodchip mulch and barley intercropping on weeds in lentil crops
Abstract: The effect of woodchip mulch on weed infestation and crop yield of lentil (Lens culinaris) was tested in a 2-year field experiment at the organic research station Kleinhohenheim, University of Hohenheim, Germany, in 2009 and 2010. The treatments included no mulch and an amount of 160 m3 ha−1 (fresh matter) woodchips (a mixture of hedgerow shrub species) applied both in spring-sown lentil sole cropping and in lentil–barley mixed cropping systems after the crops were well established. Averaged over the two years, woodchip mulch reduced weed biomass and weed density (plants m−2) in both cropping systems, with a reduction by 43% and 29% (sole), and by 51% and 30% (mixed) respectively. Compared with lentil sole cropping, lentil–barley mixed cropping decreased weed biomass significantly; however, there was no effect on weed density. Lentil grain yield from sole and mixed cropping was 3.0–3.4 t ha−1 and 2.1–2.2 t ha−1 in 2009 and 1.0–1.1 t ha−1 and 0.8–0.9 t ha−1 in 2010. Barley grain yield was 1.4 t ha−1 in 2009 and 0.7 t ha−1 in 2010. Despite decreasing weeds, the mulch did not improve grain yields of lentil or barley in mixed or sole cropping. In conclusion, the combination of woodchip mulch and mixed cropping is useful to reduce weed infestation in cropping systems where chemical or mechanical weed control is not possible and for crops with a low capacity for competition against weeds. [Wang L, Gruber S & Claupein W (2012). Effects of woodchip mulch and barley intercropping on weeds in lentil crops. Weed Research. on-line 20 Feb 2012, DOI: 10.1111/j.1365-3180.2012.00905.x]