Trade-offs in dry matter (DM) and metabolisable energy (ME) between combinations of three maize silage hybrids varying in maturity from 100-113 CRM and six winter forage options were investigated in a Waikato farmer's field over 2 years. Winter crops were triticale, cut once; oats grazed 1-2 times; and Tama and Feast II Italian ryegrass, each cut or grazed 2-3 times. Greatest DM and ME production (38.9 t/ha; 396 GJ/ha) was from a 113 CRM hybrid followed by a single-cut triticale crop. The most economical sources of DM and ME were obtained from a 100 CRM maize hybrid plus grazed oats (11.8 c/ kg; 1.12 c/MJ), while the cheapest ME source among cut winter forages was a 113 CRM maize hybrid + triticale (1.18 c/MJ). Reliable annual silage production of 30 t DM/ha and 330 GJ ME/ha (or 3000 kg MS/ha) is possible using a late maturing maize hybrid combined with a winter forage crop such as triticale, although the low feed value of the triticale may limit its use as feed for milking cows. Keywords: Italian ryegrass, oats, maize silage, supplements, triticale, winter forage crops

For the past decade maize silage has been planted at 100000 plants/ha in New Zealand. Modern maize silage hybrids have enhanced stress tolerance making them more adaptable to higher plant populations. This study examined the effect of a range of established plant populations (85000, 100000, 115000, 130000 and 145000 plants/ha) on the yield and quality of 12 Pioneer® brand maize silage hybrids grown at 13 locations over two seasons. As plant population increased maize silage dry matter (DM) yield increased significantly (P