The revival of the Bidni olive tree : a 15 year review

Abstract

A 15th year assessment of the indigenous Bidni olive (Olea europaea) was conducted across twenty sites in Malta. Tree height, trunk girth, leaf dimensions, and soil parameters (texture, pH, and conductivity) were measured using methods consistent with earlier studies (2010, 2016, and 2021). Statistical analysis including K-Means clustering of leaf morphology were performed to identify cultivar purity and potential hybridisation. Spatial mapping of growth metrics was undertaken with GIS tools to evaluate environmental and management influences. Results indicated that active grove maintenance corresponded with greater height and girth gains, while exposed coastal plots or high-salinity sites showed reduced growth. Leaf-shape clusters revealed that many trees retained classic Bidni traits (short, broad, elliptic leaves), whereas a subset displayed longer, narrower leaves suggestive of grafted or hybrid lineages. Continued monitoring and periodic genetic evaluation were recommended to safeguard the Bidni’s genetic integrity under shifting climatic conditions.