South to North   dbhg-@comcast.net   Nov 01, 2003 05:17 PST  ENTS:     After the fast pace of last week and weekend, I'm ready to slow down for a little while and revisit some of our ENTS tree lists. One area we haven't concentrated much on is North to South comparisons. Can we predict any ceilings across the range of widely distributed species and reflect realistic South to North height differentials? Presnely, not too well, but here are some examples for standing trees that extend their range well into the north and south. Numbers are rounded to the nearest foot. Species          South           North           Difference Black locust     153             126              27 E. hemlock       168             145              23 R. spruce        152             129              23 White oak        147             124              23 Bitternut H.     154             134              20 White pine       186             167              19 Tuliptree        177             158              19 White ash        163             147              16 Sugar maple      151             138              13 Yellow birch     110             101               9    N. red oak       144             135               9 Red maple        145             136               9 E. sycamore      159             153               6 Black cherry     146             140               6 American beech   136             130               6 E. cottonwood    135             133               2 Black birch      117             116               1    Hop hornbeam      73              78              -5 Bigtooth aspen    82             128              -46 Enough for now. Bob RE: More musings about ENTS and back to business   Robert Leverett   Nov 01, 2004 10:16 PST  Dale:    Yes, I do think that is a possibility, but 140 appears the absolute upper limit in New England unless the trees in the Deerfield River Gorge do something really spectacular in the next 50 years - if Tsuga survives. It is interesting to think about how such a northern tier species reaches its zenith near the southern limit of its range. The 160 to 169-foot height trees in North Carolina, South Carolina, Georgia, and Tennessee were not expected by Will Blozan and me when we set out to document the great hemlocks of the Smokies. The decrease in maximum height going north is irrefutable. In fact the decrease look to me like it follows a more predictable pattern than that of white pine. From a max of 170 at between 33 and 34 degrees latitude the maximum height drops to about 125 by 43 degrees latitude north in the Northeast. I expect that by 44 degrees that number is down to 120, if not a little less. I wonder what Lee Frelich has to say about that. Lee? Bob   Home