Irrigation and Fertilizer Placement Affect Root and Canopy Growth of Trees Produced in In-ground Fabric Containers

Abstract

Abstract Live oak (Quercus virginiana Mill.) and Chinese elm (Ulmus parvifolia Jacq. ‘Drake’) were transplanted from 3.8 liter (#1) containers into 35-cm (14 in) fabric containers in sandy soils. Irrigation or fertilizer was applied all inside, half-in half-out (50/50), or all outside the fabric container during a 2-year production cycle. For live oak, neither irrigation nor fertilizer placement increased fine root mass within the fabric container. Maximum trunk diameter was achieved by applying both irrigation and fertilizer inside the container. For Chinese elm, applying either fertilizer or irrigation inside or half-in half-outside the container increased fine root mass within the harvested root ball. Elm shoot growth was greatest with 50/50 placement of both irrigation and fertilizer. Field site influenced the effect of Irrigation on shoot growth, but not root mass. Greater fine root mass occurred in the heavier soil type