West Virginia Seed Sources of Balsam Fir

Research Bulletin 1191-99

Results and Discussion

Evaluations in the experimental planting revealed large variation in different traits of trees, not only for those from different areas (Figure 4; Table 1) but also between and within individual seed sources. Tables 2-7 provide summaries comparing averages and rankings for selected growth and foliage characteristics of trees of both vars. phanerolepis and fraseri from the six different areas from which seed collections were made. With the exception of bud development/foliage exposure comparisons in May 1996, all traits showed statistically significant differences between areas, and there were significant differences between seed sources for all traits.

Height Growth

As noted previously, trees of the Canaan Valley-Cortland Road collection were field-planted in 1986, one year after trees from the other five areas. To make heights of all trees comparable in statistical analyses, annual shoot growth for 1991 and 1996 was measured for individual Cortland Road trees, and those measurements were added to total heights that were measured in 1990 and 1995.

There was considerable reinvasion of vegetation into planting rows after trees were planted, as noted previously. As a consequence of competition from that vegetation, growth for the first few years was apparently reduced.

Differences Between Locations
Average, six-year heights of trees from different locations varied from 0.76 m for North Carolina source trees to 0.98 m for those from Canaan Valley-State Park, with the North Carolina trees being significantly smaller than those from the other areas (Table 2). Growth during the five-year period before the next set of measurements was made was much faster, with average heights of 11-year-old trees ranging from 3.08 m for North Carolina trees to 3.71 m for those from Stone Coal Run; again, there were no significant differences between the West Virginia origins (Table 2).

Figure 6. Eleven-year heights of trees of SS 389 (Stone Coal Run, left) and SS 379 (Blister Run, right).

Differences Between Seed Sources
There was large variation in heights among trees of individual seed sources and between those of seed sources from the same stand collection. Average 11-year heights were tallest (3.99 m) for trees of SS-389 from Stone Coal Run, and trees of six other families from that area were also ranked among the one-third that were fastest growing, while none were among the one-third that were slowest growing. Trees of North Carolina SS-410 were slowest growing (2.97 m), and the other North Carolina origin, SS-24, was ranked third. Of the West Virginia origin trees, those of SS-379 from Blister Swamp were slowest growing (3.15 m); however, only one other source from that area was among the slowest-growing group, while trees of five families were among the top third (Tables 2, 3, 4; Figure 6).

For 11-year-old trees of the Blister Run families, six of 10 were among the slowest growing and only one was among the fastest. For Canaan Valley-State Park families, three of 10 were among the fastest growing and three were among the slowest, while for Canaan Valley-Cortland Road families, only one was among the fastest and four were among the slowest growing (Table 3).

Differences Within Seed Sources
In addition to the variation in heights of trees from different areas and between those of different seed sources, there was considerable variation within individual half-sib families from West Virginia and the two stand collections from North Carolina. Standard deviations in six-year heights were 28 to 48 percent of seed-source means, while for 11-year heights it was considerably lower, ranging from 12 to 30 percent of means (Table 2). The range in heights of individual trees of most half-sib families was great. For example, for SS-389, the fastest growing family in the study (3.99 m, s.d. 15% of mean), the range in 11-year heights of individual trees was from 2.2-4.8 m, and for SS-379, the slowest growing (3.15 m, s.d. 22% of mean) of the West Virginia origins, the range was from 2.0-4.4 m (Table 2).