Ed,
I'm glad you're revisiting this topic. It is time that we spent list time with the bread and butter ENTS mission of computing, maintaining, and comparing Rucker Indices. I agree that the all time highest value for each species provides us with the the most appropriate measure of a site's overall tree growing capacity. Using the highest all time value for each species, MTSF has an RI of 136.35. So long as the Jake Swamp pine adds height, the RI will continue moving up, even though the current index and future RI-P indices will likely decline. Lower future RI-P values will occur because the white ash's future is grim. In addition, the American beech population will continue declining. Because of the adelgid, the future for the hemlock isn't good. And sadly, the stand that includes the champion bigtooth aspen in MTSF is now declining. The sugar maples seem to be near their peak heights, but may not decline for a number of years because there are plenty of relatively young trees that will move into peak height range as the current tallest lose crown. Of all species in Mohawk, only the white pines will continue steady gains in height. The population of young to middle-aged pines represents the great majority of pines. One species that I haven't quite figured out yet in terms of maximum site capability is the northern red oak. That species seems to be near its peak height between 120 and 130 in Mohawk. There is a significant population of 120s, but only 2 over 130 that we've found. They both seem to be growing very slowly. Bob ----- Original Message ----- From: "Edward Frank" <[email protected]> To: [email protected] Sent: Tuesday, November 3, 2009 11:51:04 AM GMT -05:00 US/Canada Eastern Subject: [ENTS] Re: King Pennisula, Allegheny River, Forest County, PA Dale, Yes I am aware that the tall silver maple tree lost a couple feet off the top. I helped you measure the later, lower number. Bob and I discussed the idea of what values should be included in a RI. The idea considered was that there should be a RI which represents the tallest trees of each species ever accurately measured on the site, and the tallest trees measured on the site at any one time. We both agreed, and I am sure everyone will, that these were two different ideas. http://www.nativetreesociety.org/measure/rucker/historical_rucker_index.htm I felt that the basic RI, or RHI, should represent the greatest height obtained for trees on the site, even of they have since lost some of their height, and that a different notation RH-P with a date would be the known Rucker index at any one point in time. A snapshot of the moment. There was not much discussion at the time, and Bob L. seemed to like my notation structure better. So for site description purposes, and for calculating the RI for a site, the numbers should be the tallest accurately measured at the site at any time. A note can be added if appropriate that a particular tree had since lost part of its crown, but it would not affect the actual RI number. Certainly if there is a strong disagreement on this data organizational structure the topic can be revisited again. Ed Frank Check out my new Blog: http://nature-web-network.blogspot.com/ (and click on some of the ads) --~--~---------~--~----~------------~-------~--~----~ Eastern Native Tree Society http://www.nativetreesociety.org Send email to [email protected] Visit this group at http://groups.google.com/group/entstrees?hl=en To unsubscribe send email to [email protected] -~----------~----~----~----~------~----~------~--~---
