Fifteen seed sources of black walnut were planted at Manhattan, Kansas (39.2°N and 96.5°W) in 1967, the western edge of its natural range. After 22 years, height, dbh, and survival measurements revealed that local trees (Kansas) and trees from within 200 miles south of the planting site grew tallest. Height and dbh correlations were highly significant and increased when compared to successive 5-yr interval measurements. Geographic and climatic variables of seed sources did not provide a significant predictive regression model. Low survival limited the success of some sources, such as two from Indiana, in this Kansas plantation. North. J. Appl. For. 9(2):41-43.
Green ash trees from 10 seed sources were planted in a test in 1961 in four states of the Great Plains Region. After more than 20 years, height growth indicates a strong interaction between seed source and plantation location. Larger trees were from southerly sources within about three degrees of latitude of the plantation site. Beyond those limits, cold injury may result. Height and dbh age-age correlations were highly significant at 8 and 20+ years. Height and dbh correlated negatively with a decrease in latitude. North. J. Appl. For. 22(1):54–58.
Forty-five full-sib families of Scotch pine (Pinus sylvestris L.) from an incomplete factorial mating design were planted in northeastern Kansas in 1981. The trees were evaluated in 1986 for survival, height growth, crown width, taper (crown width/height), number of stems per tree, the presence or absence of stem crooks, and the number of full faces. Needle length and needle color were measured at a consistent location on each tree in December 1987. Individual tree heritabilities were high; 49.68% for taper, 61.64% for crown width, 66.83% for height, and 71.46% for needle length. Estimated genetic gains showed that rapid improvements through selection are possible for these four traits. Combined selection consistently had the highest percentage gain and is the recommended selection procedure. Genetic correlation indicated that taper is negatively correlated with height (-0.651). Therefore, because of the commercial importance of form, selection for rapid height growth should not be the emphasis in future breeding efforts. West. J. Appl. For. 7(3):82-86.
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