GROWTH AND RESIDUAL EFFECTS OF LEGUME AND NON-LEGUME CATCH CROP SPECIES ON COARSE SAND

Kurzfassung

An investigation of the performance of different legume and non-legume catch crops species was carried out in 2001/02 and 2002/03 on a coarse sandy soil at Jyndevad Research Station. Eleven different catch crop species, six legumes, four non-legumes and one mixture, were tested in a field experiment with three replicates in a randomized block design. Four reference treatments without catch crops and with N-application (0, 40, 80 and 120 kg N ha-1) to the following test spring barley were included in the design. The legume catch crops, especially white and red clover, seemed to be valuable N sources for grain production on a low N coarse sandy soil type. The residual effect of the non-legume catch crops was small due to the low-N status of the soil, and there was a negative effect of chicory on the spring barley performance due to pre-emptive competition. The legume catch crops had significantly larger above ground DM production in the autumn than the non-legumes, but there was no correlation between the autumn DM production in the legume species and the residual effect on the succeeding spring barley due to different winter hardiness and different top/root ratios. Spring ploughing did not efficiently kill the chicory, sorrel and lupin plants and re-growth from the surviving roots was observed during the following three years.