This experiment was conducted to determine the effect of severe stock plant cutback on rooting in two oak species Quercus bicolorand Q. macrocarpa. Field-grown plants were either cutback leaving a 0.04-m (1.6-inch) stump above soil level or left intact (not cutback) ~1.7 m (66.9 inches) tall. Shoots arising from cutback treatments and intact plants were layered using a field layering technique and air layering, respectively. The rooting traits measured in this experiment were rooting percentage and the number of roots per shoot. Results showed significantly higher rooting percentages in layered propagules arising from severely cutback plants in both species (-77% in Q. bicolorand -70% in Q, macrocarpa) compared with air-layered shoots arising from intact plants (1% in Q. bicolorand Q% in Q. macrocarpa). Overall, pre-treatment etiolation increased rooting in shoots arising from cutback stock plants in both species. The results for the average number of roots per shoot mirrored that of rooting.
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