Legumes are the key to increasing productivity at “Inverary”, a summer moist hill / high country farm in mid-Canterbury

Abstract

About half the 4250 ha of Inverary is undeveloped
mountain land above 750 m a.s.l. There are 300 ha
of river flats, where lucerne and winter feed crops
are grown, and 300 ha conventional grass/clover
pastures. Limited areas of clover/plantain and winter
feed crops have been established at ~700 m a.s.l. on
easy rolling country. The 1600 ha of steep country,
dominated by browntop, gives low spring and high
summer production that is difficult to manage. In
2009, there were no lucerne or legume rich pastures.
The legume emphasis increased animal productivity
through improved lambing and lamb weight sold per
ewe. Total lamb meat production lifted from 230,113
kg in 2009 to 245,039 kg in 2020, despite 1000 fewer
ewes. The current sheep to cattle ratio is 60:40 with
13,000 stock units being wintered. Pre-development,
a major shortage of nutritious forage in early spring
was compounded by difficulty controlling reproductive
grass in summer and autumn. In 2016, total production
of legume dominant pastures was 40% more than sown
grass/clover pastures with limited nitrogen fertiliser
(15 vs. 11 t DM/ha/year). In early spring, legumes
had higher growth rates of conventional grass/clover
pastures (90 vs. 44 kg DM/ha/day), whereas browntop
dominant hill pastures grew 10 kg DM/ha/d and 5 t
DM/ha/yr.