Epiphyte-host relationships of remnant and recombinant urban ecosystems in Hamilton, New Zealand: the importance of <italic>Dicksonia squarrosa</italic> (G.Forst.) Sw., whekī.

More than a thousand iNaturalist NZ observations were compiled and analysed to determine common vascular epiphyte-host relationships in Hamilton, North Island, New Zealand. <italic>Dicksonia squarrosa</italic> supported the most epiphytes, followed by <italic>Salix cinerea</italic>, <italic>Melicytus ramiflorus</italic> and <italic>Cyathea medullaris.</italic> Epiphytes displaying stronger host specificity, such as <italic>Tmesipteris elongata</italic> and <italic>Phlegmariurus varius</italic>, were often on <italic>D. squarrosa.</italic> In comparison, generalist epiphytes, including <italic>Pyrrosia eleagnifolia</italic> and <italic>Lecanopteris pustulata,</italic> were mainly on <italic>M. ramiflorus</italic> and <italic>S. cinerea.</italic> A detailed study of 60 <italic>D. squarrosa</italic> in a single gully investigated factors supporting the host quality of <italic>D. squarrosa</italic>. <italic>Dicksonia squarrosa</italic> diameter at breast height (DBH), height, caudex surface area, and distance to the stream and vegetation patch edge were measured. <italic>Dicksonia squarrosa</italic> that hosted epiphytes were significantly taller, further from the patch edge and had a larger surface area. Epiphyte species richness was higher on <italic>D. squarrosa</italic> further from the patch edge. The epiphyte communities examined are likely characteristic of highly modified urban ecosystems. Future research investigating the impact of host traits and microclimate on epiphyte-host networks is required to fully elucidate these relationships in urban environments. [ABSTRACT FROM AUTHOR]