(168) Long-term Growth of Live Oak from Seed or Cutting

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  • 1 1Texas A&M University System, Horticultural Sciences, Texas Agricultural Experiment Station Weslaco, TX, 78596
  • | 2 2Texas A&M University System, Horticultural Sciences, Texas Agricultural Experiment Station, El Paso, TX, 79927

Live oak trees raised from acorns are highly non-uniform and many produce numerous undesirable rhizomic shoots. The objectives of this study were to 1) compare the growth rates between (Quercus virginiana Mill.) trees from seed and cutting in four production systems and 2) determine if trees from cuttings produce rhizomic shoots. Rhizomic shoot cuttings 25–30 cm long were taken from a single tree about 50 years old in late Aug. 1990, rooted, and planted in 2.6-L pots after 2 months. During the same week, acorns were collected from the same tree and germinated. All trees were planted into 13-L pots in July 1991 and then to a field in July 1992. Trees from both sources were planted either directly in the ground, in 36.6- or 45.7-cm-diameter polypropylene fabric bags buried in the ground, or in 13-L pots on the ground. Trunk circumference 10 cm above the soil line was roughly measured yearly between 1992 and 1999. Initially, trees from cuttings grew slightly slower than seedlings, having a smaller trunk circumference, diameter, and cross-sectional area. These differences diminished and all trees had similar circumferences after 1996. In 1992, trees in 36.6-cm bags and pots had more growth than trees in the ground. In 1993, trees in pots had better growth than those in the ground. After 1993, all trees had similar circumferences until the end of this study, probably due to roots extending beyond the bags and pots into the surrounding soil. About one-third of the seedling trees produced rhizomic shoots, whereas none of the trees from cuttings did. The rhizomic shoots of trees in pots were contained within the pot and none from the ground. Another significance of this research is that the cloned trees from cuttings were extremely uniform in growth habit and form.