Scots pine; Plants--Variation; Trees--Growth
Scotch pine exhibits clinal variation from north to south in two characteristics: viz., the number of days after April 15 to the time of maximum rote of height growth, and total height after the age of 17 years. There is east-west clinal variation with respect to two characteristics: viz., the number of days after April 15 to the beginning of height growth, and to the time of the maximum rote of height growth. The twelve out of the fifteen varieties analyzed showed the existence of valid sub-varieties or ecotypes. Varieties from central Europe were the fastest growing in each of four planting sites in Minnesota. Significant mortality was noticed among the seed sources from the 40°-45° N. latitudinal class, in six outplantings. Production of lammas shoots was found to be under strong environmental influence. The seed sources from the 50°-55° N. zone were found to be the most highly susceptible to attack by the white pine weevil (Pissodes strobi Peck.).
Khalil, M. A.
Scotch Pine: Variation and Performance in Minnesota.
Journal of the Minnesota Academy of Science, Vol. 35 No.2, 114-117.
Retrieved from https://digitalcommons.morris.umn.edu/jmas/vol35/iss2/16