Creators:

Peter Harrison (0000-0002-3502-0242)

Co-Creators:

Joao Costa e Silva (0000-0003-1422-9554) , Brad Potts (0000-0001-6244-289X)

Biological Sciences

Estimated least-squares means for the 22 geographic regions (paired populations of E. ovata and E. pauciflora), the associated bioclimate variables and the derived principal components that summarises the bioclimatic data into three independent gradients. Multiple individuals of each species from each geographic region were planted in a common-garden field trial, inside and outside a herbivore exclusion zone. Height data is from age 3-year measurements and survival data is from age 8-year assessment.

Height data is off 3-year old individual plants; survival data is from 8-year old individual plants

For both eucalypt species, the planted families were derived from open-pollinated seed, obtained from well-spaced (> 100 m) mother trees sampled in native populations across their eastern geographic range in Tasmania. The populations of both species were sampled in pairs from each of 22 specific geographic areas, which were chosen to represent regions where the species’ natural distributions overlapped. Within each field trial, the families of each species were arranged randomly and independently of their population of origin, using an experimental complete block design comprising eight blocks. Each block was arranged as a rectangular grid with an inter-tree spacing of 3 m (between rows) by 2.5 m (within rows), and each family was represented as a single-tree plot. The experimental designs of each species were then superimposed spatially, with each alternate position along a row planted with a different species, and rows offset so that the four nearest neighbours of a focal tree were trees of the other species. The assessment of height growth was undertaken at age 3 years. Growth performance was assessed by using maximum tree height (m), measured with height poles. At age 8 years from planting, tree survival was scored as a binary outcome whereby a tree was classified as dead (scored as 0) when no live plant tissue was evident above ground or the plant was in very poor vegetative health, otherwise it was classified as alive (scored as 1).