Factors influencing the contribution of narrow-leaved plantain to North Island hill country pastures

Abstract

We examined the contribution of narrow-leaved plantain (Plantago lanceolata) to pasture production and composition, as part of a larger experiment evaluating the role of biodiversity in North Island hill country pastures. Plantain was sown at rates between 0 and 13.5 kg/ha (equivalent) into small plots at two sites representative of North Island hill country pastures - Whatawhata and Ballantrae Research Centres. The sites encompassed variation in both slope and soil fertility. We measured the abundance and percent composition of plantain, and the total yield of the herbage growing on the plots in the spring and autumn of the year following establishment. The average abundance of plantain in both spring and autumn was greater on higher fertility plots but was not different between easy and steep slopes. Abundance was also related to sowing rate and the contribution of plantain to harvested DM yield was strongly related to abundance. There was some evidence that the percentage of plantain in spring pastures was positively related to total plot yield. Given that plantain occurs ubiquitously in most pastures, contributing 2-8% of pasture productivity, the data indicated a sowing rate of approximately 1 kg/ha was a minimum to significantly increase the abundance and contribution to productivity of this species. Keywords: biodiversity, hill country, pasture, plaintain