West Virginia Seed Sources of Balsam Fir

Research Bulletin 1191-99

Tree Shape

Tree shape/outline is an important factor contributing to the desirability/quality of Christmas trees. This trait is usually improved through shearing and shaping. However, having trees that are inherently conical would be very desirable and could reduce shearing costs. In this study, trees were subjectively evaluated for tree shape/outline using a three-point rating system: 1 = irregular, 2 = moderately irregular, and 3 = conical.

Differences Between Locations
The average shape of trees of the North Carolina origin was significantly best (2.4 - moderately conical to conical), while it was poorest (1.8 - slightly below the moderately irregular rating) for trees of the Canaan Valley-Cortland Road families. For trees of the other four West Virginia collection areas, average shape ranged from 2.0 to 2.2 - at or slightly above the moderately irregular rating (Table 5).

Differences Between Seed Sources
Of the 50 families/stand collections, average shape was best (2.61) for trees of SS-384 from Stone Coal Run, and five of 10 trees from that area were among the top one-third evaluated. For other areas, seven seed sources from Blister Swamp, both North Carolina sources, two from Blister Run, and one from Canaan Valley-State Park were among the top ranked. Trees of SS-416 had the poorest average shape (1.67), and trees of all but one of the eight families from that area were included in the lowest-ranked group, while six from Canaan Valley-State Park, three from Blister Run, and one from Stone Coal Run were in the lowest-rated group (Tables 3, 4, 5; Figure 12).

Figure 12. Conical (SS 384, Stone Coal Run, left) and irregular (SS 416, Cortland Road, right) shapes of 14-year-old trees.

Differences Within Seed Sources
As noted for other variables, differences in tree shape within individual collections were relatively large. Standard deviations ranged from 18 to 42 percent of seed-source means, with trees of the two North Carolina collections both at 18 percent (Table 5). For trees of SS-384, which had the best average, the range in ratings for individual trees was from 2.0 (moderately irregular) to 3.0 (conical), while for those of SS-416, which had the poorest average rating, the range was from 0.5 (very irregular) to 2.5 (moderately irregular to conical) (Figure 8).