An ethnobotanical study of the effects of nutrient application, temperature and pH on the growth and development of bracken fern, Pteridium esculentum (Forst.f.) Cockayne : A dissertation submitted in partial fulfilment of the requirements for the degree of [Bachelor of] Horticultural Science with Honours at Lincoln University

Abstract

The objective of this study was to establish the effects nutrient application, temperature and growing media pH had on the growth and development of Pteridium esculentum. Pteridium esculentum or bracken fern was utilised by pre-European Maori as a major food source, supplying carbohydrates. Its ecological distribution was modified by the Maori as it was periodically 'burnt off' to stimulate new growth for 'aruhe' or fern root harvesting. Old kumara plots were often invaded by bracken fern as it is an aggressive coloniser of wastelands.

Experiment 1 was undertaken to investigate the best means to vegetatively propagate bracken from rhizome segments for use in a pot trial. It was found that rhizomes of bracken can be propagated in a fresh sawdust media with warm temperatures and minimal temperature variability.

Experiment 2 investigated the response of bracken to differing nutrient application rates, temperatures and pH levels. Significant responses were observed in chlorophyll contents at differing pH and temperature ranges. Temperature and pH had insignificant effects on all other variates measured. However certain trends were evident. Insignificant responses to nutrient application were found for all variates measured.