Black, AlistairLucas, Richard2019-09-082018-11-13Black, A.D., & Lucas, R.J. (2018). Dry matter yield of dryland and irrigated mixtures of Caucasian clover, white clover and perennial ryegrass over 5 years at Lincoln University. Journal of New Zealand Grasslands, 80, 73-80.2463-2872https://hdl.handle.net/10182/10921This experiment investigated the effects of Caucasian clover (CC), white clover (WC), perennial ryegrass (RG) and their mixtures on dry matter (DM) yield under dryland and irrigated conditions over 5 years (1st July-30th June) at Lincoln University. Seven mixtures of the three species (three pure, three binary and one ternary) were sown in November 1999, grown with and without irrigation, and grazed by sheep. Total annual DM yield in Years 2-6 (2000/2001-2004/2005) was analysed. Clover-RG mixtures yielded more than the average monoculture yields of their constituent species (over-yielding). This diversity effect was 1.8-7.0 t DM/ha for WC-RG over all 5 years and 2.7-4.6 t DM/ha for CC-RG in Years 3-6. There was no additional yield benefit from the three-species mixture. Diversity effects were due to synergistic interactions between the clovers and RG, which were similar for CC and WC once established. The interspecific interactions persisted despite changes in botanical composition across irrigation levels and years.pp.73-80en© 2018 The authors and New Zealand Grassland Association. This work is licensed under a Creative Commons Attribution-Non Commercial-NoDerivatives 4.0 International License. Rights granted to the New Zealand Grassland Association through this agreement are non-exclusive. You are free to publish the work(s) elsewhere and no ownership is assumed by the NZGA when storing or curating an electronic version of the work(s). The author(s) will receive no monetary return from the Association for the use of material contained in the manuscript. If I am one of several co-authors, I hereby confirm that I am authorized by my co-authors to grant this Licence as their agent on their behalf. For the avoidance of doubt, this includes the rights to supply the article in electronic and online forms and systems.competitiondiversityLolium perennepastureTrifolium ambiguumTrifolium repensweedsJournal ArticleANZSRC::0703 Crop and Pasture ProductionANZSRC::070302 AgronomyANZSRC::079901 Agricultural Hydrology (Drainage, Flooding, Irrigation, Quality, etc.)ANZSRC::0503 Soil Sciences2463-2880https://creativecommons.org/licenses/by-nc-nd/4.0/Attribution-NonCommercial-NoDerivatives