Native/ Exotic Rucker Indicies
  Dec 29, 2005 15:41 PST 

.. I'll add
Latodami Nature Center to our PA RI list. I'm afraid I plan on modifying what
you have in the RI list though to keep the rest of our PA list consistent.
You'll see in the RI list for Latodami below, that I excluded the planted
trees. ..
Re: Latodami Rucker Index   Edward Frank
  Dec 29, 2005 17:35 PST 

ENTS, Dale,

In Carl's original post he included Norway Spruce that had been planted in
the Rucker Index for the site. Dale recalculated the RI to include only
non-planted trees. I understand we are the eastern NATIVE tree society, but
how should we, as a group, deal with planted and non-native trees when
calculating a Rucker Index for a site? Should these trees be excluded, or
should they be included in the calculated RIs? Whichever position you
choose, what reasons do you have for this position?

Ed Frank
RE: Latodami Rucker Index   Will Blozan
  Dec 29, 2005 17:57 PST 


I think the exotics should be excluded. The only potential gray area I see
is when they are in a forested situation as an impressive canopy species and
may represent a component on a site lacking 10 species. Even so, I would
just note that, exclude it and the resulting lower Rucker for the site would
reflect it's dearth of tall trees and species. For example, the Biltmore
Estate here in Asheville, NC has three European species right around 130'.
They would all make it into the Rucker since the native forests are so
short. There is also a 145' eastern hemlock on the Estate, one that I would
include in the Rucker for the site even though it was planted.

Since I have been diagnosed with "Gymnophilia" I find exotic conifers very
interesting to track. I find the heights obtained throughout our area
valuable data to collect. The eastern Rucker for introduced European and
Asian conifers would be interesting to compare to their native counterparts.
Same for the hardwoods. They could reflect latitudinal or environmental
influences on size that are mirrored (or reversed) in their native lands.

RE: Latodami Rucker Index   Carl Harting
  Dec 29, 2005 19:04 PST 

Dale, Will, Ed,

I wasn't 100% sure if the planted species should be included in the
Rucker Index and that's why I made sure to note them. I'm a bit
confused about the pin oak being excluded and the white pine included
though. Both species are native to Western PA, so what criteria would we
use to exclude one but not the other? I'm not arguing to raise the
index for this particular site, but wondering in general how to proceed
in the future. Do we go with what is native to the state, county, or
site? In this particular case, white pine does exist elsewhere on the
site, while pin oak doesn't.

Re: Latodami Rucker Index   Edward Frank
  Dec 29, 2005 19:36 PST 


There are a several questions that come to mind:

1) What if there is evidence that the exotic species is reproducing or
grew from a naturally reproduced seed?
2) How can you be sure if a native species has naturally grown or has been
planted? So cases it would be obvious, while in others it might be
difficult to determine - a tree in an old park could have been left behind
when the rest were cleared, or they could have been planted early in the
parks history.
3) Should trees native to the region be excluded from the index because they
were planted?

RE: Latodami Rucker Index   Roman Dial
  Dec 29, 2005 22:59 PST 


I like the idea of exotic Ruckers, too, for the same reasons you gave --
to compare with what the trees do in their native homes. But I also
agree that Native Ruckers for a site are most important. In fact, does
anybody know how many species have max tree heights for a species that
are taller outside their original range than inside their native range?
I understand the tallest American Chestnut is out west, and likely some
other trees that were hit catastrophically by pathogens, but what aout
other species?

Rucker Index   Darian Copiz
  Dec 30, 2005 07:42 PST 


In my opinion:

1) It is a great idea to take measurements for naturally occurring
exotic species, especially since they are now a part of the ecosystem
and in most cases will be staying a part of it. Although personally I
would rather not see bird cherry, Norway maple, or some other exotic
species in our forests I don't think we can just ignore them. What the
RI includes depends on what the RI will be used for. I prefer a 100%
native RI for the base RI - it should be the closest to describing a
site in its natural state. However, a supplemental RI that includes
naturalized and/or planted species might tell us something about our
changing landscape and what difference the "new natives" make. At the
least, having measurements for exotic species is certainly useful.

2) This is a judgment call based on habitat, history, and various
clues. The better a person knows the site, the surrounding region, and
what species should occur there, the easier it is to tell what is

3) Related to the above, these are the most difficult to determine
whether they were planted or not, but I think they should be native to
the site, rather than native to the regeion in order to be part of the
base RI. If the species does not occur naturally on the site it should
be part of the exotics/planted included RI. Of course the actual tree
could come from a different region, but many of the older trees most
likely come from local populations.

RE: Latodami Rucker Index   Will Blozan
  Dec 30, 2005 08:01 PST 


I would say if pin oak doesn't occur naturally on the site, then note it as
non-native and exclude it. (VERY impressive height, BTW!)

Re: Christmas and the day after
  Dec 31, 2005 09:17 PST 

    I'll throw my 2 cents worth in on RIs for non-native species. I think we should make room for both. Where species like Norway spruce, white fir, Norway maple, European beech, etc. are entrenched, I for one am curious on how well they do. I would always want to distinguish between native and non-native and indices that include all of one type or the other or a combination.

RE: Latodami Rucker Index
  Jan 03, 2006 06:13 PST 


I side with Will on this. I'm definitely all for measuring them. We just need
to make a note if we decide to include them in an RI for various reasons.


At the moment, I just included all the unplanted species for Latodami in your RI
for the site. It just happens that your planted white pine was shorter than the
unplanted one. In my travels, I usually find the top canopy trees at a site are
non-planted natives with planted natives being on the fringe shorter.

I see Will's point about Biltmore... a planted native that makes it into the RI.
I see nothing wrong this, it just depends on how you want to define a specific
area.    For the most part, I'm looking at defining top canopy components in a
forested setting. Park-like planted settings are different. I'd say just
measure them, and make a note of what you're trying to describe.