Hello Everyone - Chris Strother

[cwstrother]

Hi,

My name is Chris Strother and I am the Geospatial Technology Research Associate at the University of North Georgia. I recently completed my M.S. in Geography at UGA, where my thesis focused on tree heights in the Tennessee portion of the GRSM. I have identified 10 sites in the TN side which contain tall trees over 52 m using airborne lidar data. The report has been submitted to Paul Super at the NPS. I would be interested in discussing further with anyone who would like to know more about my research.

Cheers,

Chris

[dbhguru]

Chris,

Welcome aboard. I think it is safe to say that we're all interested in your research and results and would be interested in what you are finding. We use LIDAR quite a bit to identify tall tree hotspots and then go in and ground-truth them. Will Blozan, Josh Kelly, Michael Davie, Jess Riddle, and others are heavily involved in verifying LIDAR hits. They can discuss with you where they find the LIDAR data to be most accurate and where they've encountered problems and the nature of those problems. It was from a LIDAR hit that they discovered and then confirmed the 191.9-foot tall Liriodedron tulipifera in NC. The tree was climbed and tape-frop measured. You may have read about that.

Again, welcome aboard.

Bob

[eliahd24]

Welcome aboard Chris! I'm a fellow member just down the road in Atlanta. I second Bob's comments. You're in good company with the best of the best "big tree hunters" in the east. Heck, Will Blozan has even helped climb, measure and volume map the giant sequoia's out west with none other than Steve Sillett.

Do you plan to "ground truth" the Lidar hits? I know that ground expeditions are sometimes (often?) a let down when you find out trees are leaning over a deep ravine and thus giving false height readouts on Lidar. I can almost guarantee you that Will, Jess, Josh, etc. will have great insight into the areas where you noticed high numbers.

Happy to have you here and I hope that you post often. Best of luck with your research,
Eli

[Will Blozan]

Welcome Chris!

Indeed, NTS members are in possession and processed much of the TN LiDAR. Recon trips have been both highly disappointing (crown abnormalities, heavy lean, steep slopes) and exciting- several tuliptrees over 180' and a super tall bitternut hickory (sorry- don't recall the numbers). In old-growth forests the TN LiDAR is highly unreliable based on the few trips so far. However, in second-growth it is comparable to more coarse NC coverage and has us hopping with excitement. The NC Tuliptree Study has just been extended through 2014 at which time we may move to the TN side. You can search the BBS for posts of all these trips,

Wil

[cwstrother]

Will et al.,
Thanks for the responses. My particular work created a methodology for processing all of the lidar data for the TN collection. I ranked the top 10 sites that were above 52 meters. The 2 tallest hits that I found were in the Abram's Creek area in the western portion of the park. There were also several trees in a cluster on the north slope of Bote Mtn. There was also a particularly interesting 3-trunked white oak just off of Little River Road. Again, Paul Super has the coordinates if you're interested in a list of the tallest hits in TN for the whole dataset.

Best,
Chris

[dbhguru]

Chris,

Thank you very much for the offer. I think that I speak for the entire group when I say that we're very interested in the whole TN dataset. What we are also interested in is a partnership with the LIDAR architects to ground-truth specific hits and help analyze the factors that lead to better or poorer results. I have no doubt that the technology will advance and we'd like to be in on the ground floor. One of our members, Don Bertolette, up in Alaska, recommended several years ago that we investigate the technology, and some of the North Carolina Ents, followed by some in Ohio began using LIDAR data to great advantage. From my understanding, certain types of terrain and tree crown shapes produce extremely good results, and the opposite is also true, but we need to get more specific and that could be done through a partnership.

So far, we have nothing to work with here in Massachusetts. I am hoping that situation will change. Again, thanks for the generous offer.

Bob

[Will Blozan]

Will et al.,
Thanks for the responses. My particular work created a methodology for processing all of the lidar data for the TN collection. I ranked the top 10 sites that were above 52 meters. The 2 tallest hits that I found were in the Abram's Creek area in the western portion of the park. There were also several trees in a cluster on the north slope of Bote Mtn. There was also a particularly interesting 3-trunked white oak just off of Little River Road. Again, Paul Super has the coordinates if you're interested in a list of the tallest hits in TN for the whole dataset.

Best,
Chris

Chris,

I think you may have relayed some of your findings to Michael Davie already? Were some of the "hits" ground-truthed with tangent height routines, perhaps?

So far we have found an extraordinary amount of leaning trees on steep slopes in the TN LiDAR data. Second-growth stands such as Burnt Ridge near Elkmont were legit hot spots. The Abrams Creek hits are likely leaning white pines but "juicy" terrain could justify a trip...

Will

[cwstrother]

Chris,

I think you may have relayed some of your findings to Michael Davie already? Were some of the "hits" ground-truthed with tangent height routines, perhaps?

So far we have found an extraordinary amount of leaning trees on steep slopes in the TN LiDAR data. Second-growth stands such as Burnt Ridge near Elkmont were legit hot spots. The Abrams Creek hits are likely leaning white pines but "juicy" terrain could justify a trip...

Will

Hi Will,

Michael went out to the False Gap area early in the process, and I've sent him a personal email giving some general idea of how the rest of the research went. I was able to ground-truth 7 of the 10 sites with varying success. I used an Impulse clinometer/rangefinder. Only one site was way-off and that was a leaning white pine on an extreme slope. The others were promising. I was able to access these areas with an assistant in a two day time period, so I think it would be worth a shot. Thanks for your response,

Chris

[Will Blozan]

Chris,

Awesome. What is the word on the white oak? Are you using the VD function or built in height routine? As accurate as the laser is, the height routine is nearly worthless, and highly prone to error in standard use.

Will

[Jess Riddle]

Hi Chris,

I’m extremely interested in your thesis work. The tall canopy forests you’ve located are of course a major point of interest, but I’d also like to hear about the potential applications for your research, what prompted the research, how you processed the data, and your thoughts about potential ways to improve estimation of individual tree height.

I’ve used LiDAR to make canopy height models for most of the smokies, and made other models for north Georgia, which seems to have LiDAR data generated with the same methods and equipment as the TN side of the Smokies. I’ve also visited that Bote Mountain stand you mentioned, and found the trees to be impressively tall, but not quite as tall as the LiDAR model indicated.

I’m looking forward to your future posts.

Jess