Developing A Simple Water Use Model of Ilex x ‘Nellie R. Stevens’ from Liners to Four Meter Tall Trees

Abstract

To meet minimum spring flows, water management districts in Florida sought to make both agriculture and urban landscapes water efficient, which includes tree farms. Ilex spp. (holly) trees are endemic to Central Florida and among the most popular landscape trees for their hardness, bright colors and go-anywhere size. To provide a basis for irrigation allocations both during production and in landscapes, daily actual evapotranspiration (ET_A) for three holly trees were measured with weighing lysimeters over 5.75 years, beginning with rooted cuttings and continuing until trees averaged 4.3 meters in height. Empirical models were derived to calculate ET_A based on crown horizontal projected area or trunk caliper, adjusted daily by changes in evapotranspiration (ETo). Average ET_A to produce these hollies was 20 432 L cumulative over 5.75 years.