MWRPP Report 14.3 Investigation into the water regime requirements of Eucalyptus camphora subsp. humeana (Mountain Swamp Gum).

This report details findings from investigations into the water regime requirements of Eucalyptus camphora subsp. humeana (Mountain Swamp Gum). These investigations were commissioned by Melbourne Water in September 2012 following a scoping study that highlighted evidence for the role of water regime in dieback of the species within the Cockatoo Swamp (Yellingbo Nature Conservation Reserve) and the lack of detailed knowledge of its water regime requirements. Importantly, E. camphora stands within the Cockatoo Swamp are the key component of the FFG listed ‘Sedge-rich Eucalyptus camphora swamp community’, and are critical habitat for the endangered Helmeted Honeyeater and Leadbeater’s Possum. The investigations focused on three stages of the life-cycle of E. camphora: flowering phenology and seed release, seedling establishment and growth, and the maintenance/survival of mature trees. The reproductive phenology (seasonal timing of flowering, seed release, etc.) of E. camphora was monitored at Yellingbo using funnel traps; the effect of water regime on the establishment and growth of E. camphora seedlings was tested in nursery-based flooding experiments; while the association between water regime and tree condition was explored using a recently developed hydrologic model and tree condition survey data.