Propagation of Shrub Live Oak from Cuttings

Softwood cuttings of shrub live oak (Quercus turbinella Greene) were rooted in a laboratory chamber supplied with intermittent mist, 1,600 ft-c illumination, 30 C rooting-medium temperature, and 25 C air temperature. Rooting-medium temperature was selected by means of a temperature versus root-growth response curve for germinating acorns. Average rooting percentage was 75% with soft fully expanded cuttings and with hardened cuttings (taken at the completion of a flush of growth) in a 1:1 mixture of perlite and peat moss; the overall rooting percentage for these cuttings in six media was 51%. Both soft fully expanded and hardened cuttings were superior to succulent cuttings in the elongation stage. A 1:1 mixture of perlite and peat moss was superior to perlite alone as a rooting medium. Repeated foliage sprays of 3-indolebutyric acid (IBA) on cuttings in the rooting chamber did not increase rooting. Hardened cuttings were most resistant to decay. Excessive callus formation was common, occurred most frequently in perlite alone, and was not influenced by IBA foliage sprays.