Loblolly pine cutting morphological traits: Effects on rooting and field performance

Shoot cuttings were harvested from four-year-old, loblolly pine hedges in M arch and September of 1987, and placed into a series of factorial combinati ons of cutting length, diameter class, and the presence/absence of a termin al bud to assess effects on rooting and field performance. Average rooting in the March trial was 50 percent and only 20 percent for the September tri al; however, the best treatment in March yielded 100 percent rooting. Termi nal bud status did not appear to influence percent rooting. Shorter cutting s (5.1 or 7.6 cm) with an average diameter of 2 or 3 mm tended to root bett er and develop more roots. Field performance of the rooted cuttings through age five suggests that the original cutting does not require a terminal bu d, but the best set of morphological traits differ depending on bud status. Considering both rooting ability and field growth with an original tip bud present, the best cutting dimensions were 5.1 or 7.6 cm long and 2 or 3 mm in diameter. Without a tip bud present, cutting dimensions were restricted to 7.6 or 10.2 cm long and 3 mm in diameter. Number of main roots was a we ak predictor of tree height or dbh at age five.