108 Table 1. Survival, height, and dbh rankings of top and bot- tom 10 eastern redcedar seed sources at 23 years. Source # 5334 7315 7522 10235 10722 6315 7515 10713 10213 Mean State Top 10 Sources 7514 Nebraska Nebraska Iowa Survival (%) 100 a z South Dakota 100 a Kansas Kansas 100 a 100 a 100 a 95 a South Dakota 85 a Nebraska Iowa 120 other central sources Mean Bottom 10 sources 8613 8514 8623 8625 8615 13321 8612 8714 13323 13324 Mean Mean Texas Texas Texas Texas Texas Texas Texas Texas Texas Texas All 140 85 60 a 60 a 45 a 30 a 45 a 20 a 40 a 30 a 10 a 40 a 38 78 zLetters indicate significance differences. (10.2 to 20.3 ft). Specific patterns were found geographically for total height. The tallest trees (10) had high survival (100%) and were also generally in the upper 10% of dbh [12.9 cm (5.1 in)]. The shortest 10% of the sources were from Texas [4.2 m (13.9 ft)]. Diameter Seed sources (Table 1) were significantly different at the P < 0.01 (analysis of variance). The mean dbh was 10.9 cm (4.3 in) with a range of 2.5 to 14.5 cm (5.7 in). Specific patterns were found, geo- graphically, for diameter measurements. The largest diameter trees were from Iowa [14 cm (5.5 in)]. Sources from the central plains were generally the largest; mean survival was approximately 85%. Other Variables The mean value of the number of stems per tree for the en- tire planting was 1.6, with a range of 1 to 3.3 stems per tree. Nearly 15% of the sources showed a consistent trend toward a single-stem habit. No geographic pattern was recognized. Crown density was good for most sources planted, with rat- ings ranging from medium to dense for windbreak character- istics. However, Southern Texas sources were found to have sparse to very sparse crowns. Over 90% of the sources had branch angles between 45 and 90°. All sources had good vigor and were generally healthy showing minimal crown damage. Cluster Analysis Cluster analysis included all 140 sources. The analysis dif- ferentiated 3, 4, and 5 clusters for height, with a significance ©2009 International Society of Arboriculture Figure 1. Performance clusters of eastern redcedar seed sources representing natural stands based upon Ward’s method. The plus sign indicates the location of test plantation. 100 a 90 a South Dakota 85 a 94 Height m (ft) 6.2 (20.3) a z 6.2 (20.2) a 6.2 (20.2) a 6.2 (20.2) a 6.1 (20.0) a 6.1 (20.0) a 6.1 (19.9) a 6.1 (19.7) a 6.0 (19.7) a 6.0 (19.6) a 6.1 (19.9) 5.4 (17.6) 4.0 (13.1) a 3.9 (12.8) a 3.8 (12.6) a 3.7 (12.2) ab 3.6 (12.0) ab 3.6 (12.0) ab 3.5 (11.6) ab 3.5 (11.6) ab 3.2 (10.5) ab 3.1 (10.1) ab 3.6 (11.8) 5.3 (17.5) Dbh cm (in) 13.2 (5.2) a z 12.7 (5.0) a 13.7 (5.4) a 13.7 (5.4) a 13.5 (5.4) a 13.0 (5.1) a 13.0 (5.1) a 12.7 (5.0) a 14.0 (5.5) a 12.7 (5.0) 13.2 (5.2) 11.2 (4.4) 6.6 (2.6) fghi 6.6 (2.6) fghi 5.6 (2.2) fghi 1.2 (3.2) jk 5.3(2.1) hj 6.3 (2.5) fghi 5.6 (2.2) fghij 4.3 (1.7) jk 2.5 (1.0) k 4.1 (1.6) jk 5.6 (2.2) 10.9 (4.3) Geyer et al.: Eastern Redcedar Seed Source Test that was P < 0.01 for height, survival, and dbh. The other vari- ables listed were deleted in the analysis because of similar val- ues. General patterns of variation were identified by using this analysis. Distinct geographic patterns were shown in the all of the clusters evaluated. The 5-cluster analysis was selected as it most clearly indicated geographic source patterns of variation (Figure 1). A similar arrangement was found in South Dakota for 10-year-old eastern redcedar (Schaefer 1995), with the excep- tion that Texas sources were not considered. Cluster values are shown in Table 2. The height values for first through fifth clusters were 5.8, 5.4, 4.9, 4.2, and 3.5 m (18.9, 17.6, 16.1, 13.9, and 11.4 ft), dbh values were 13, 11.7, 9.7, 7.4, and 4.6 cm (5.1, 4.6, 3.8, 2.9, and 1.8 in ). The two Texas sources were the shortest. Correlations Age/age correlations between height and dbh, were particularly high. Height growth at 5 years (Table 3) predicted the tallest trees at 10 years (Pearson correlation coefficient = 0.960). Height at 10 years (Table 3) predicted height at 23 years (0.945). Five-year data was not available for determining 23-year relationships, but one could assume that the correlations would be high. The tallest trees had the largest diameters (correlation = 0.930).The other major variables and the geographic traits did not provide any significantly high correlations to predict growth (Table 3).
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