Search found 43 matches

Return

Re: 3D spacial modeling of a giant redwood trunk

All,

Somevery intersting stuff going on here, and it is starting to get very similar to the stuff I do for a living. I work as an engineer, and part of the work we do involves reverse engineering of reasonably complex engineering components (pressure casings, turbine scrolls) to help assess remenant service life. One way we capture the geometrical information is using a handheld 3d-laser scanner ( http://www.zcorp.com/en/Products/3D-Scanners/ZScannerandtrade-700/spage.aspx ). These can be used for scanning objects up to car-sized at quite high resolution. The resulting point clouds are then imported into reverse engineering software, and the analysis can be performed on the resultant 3-d models. The particular method of scanning used in this product is resonably manually intensive - reflective spots placed approximately 4 inches apart over the surface to be scanned is required. This is not our core business, but it is a valuable tool we can draw upon as required. The company producing this scanner advertises a variant that can be used for recording archeological geometry

I know of another engineering company in Europe doing reverse engineering of large power station turbine rotors (3 or 4 m in diameter, 10 m long) using (semi)portable structured light scanning (http://en.wikipedia.org/wiki/Structured-light_3D_scanner).

Another company I used to work for was developing another handheld laser scanning system, and was looking at room-sized objects (e.g. http://www.irl.cri.nz/newsroom/news/setting-scene-3d-revolution ).

These techniques are all used to automate the manual acquistion process that Michael is performing. I do not know of any particular outdoor scanners, e.g. for surveying/mapping, but I know they exist, and are available at a price - our basic laser scanning setup at work is more than $100k, hardware plus software, but this is for the required resolution - tree measurement may not be as demanding.

Cheers,
Matt
by fooman
Fri Dec 30, 2011 10:05 pm
 
Jump to forum
Jump to topic

Re: 3D spacial modeling of a giant redwood trunk

Hi Michael,

The laser scanner we use is not a Lidar scanner - it does not use a reference position to generate the point cloud. It provides self positioning data via reflective spots that are randomly positioned on the scanned object. Once these points are registered the laser beam is scanned across the object, much like a spray can, "painting" the scanning beam across the object. This generates reasonably high resolution data (sub-millimetric) very rapidly - maybe a million points in an hour or so. But not really suitable for a large tree.

Another scanner I came across used self positioning in the magnetic field as some sort of golbal reference, but it could not scan metallic objects, so wasn't much use for us.

I've just remembered that our inspection division used to scan the inside of delayed coker drums (large refinery vessels - maybe 20-30 m tall, 4-5 m in diameter) using a laser process - a rotating prism was used to scan a beam around the inside circumference of the vessel, while being dropped down the axis, to pick up cracking/bulging in the vessel wall.

I do think structured light scanning is a real possibility for large trees - all that is needed is a reference dimension (e.g. taped girth) or length between two features on the trunk, a method to project a light pattern (a large projector at night?), and two cameras recording the image at a known baseline plus the software. The guys at the company I referred to in my earlier post were just using normal cameras mounted on tripods a known distance apart. The resolution of a scanned tree would be lower than the smaller objects normally scanned (e.g. people) but I guess +/- 1 inch would be ok for volume, rather than +/- 1 mm?

Cheers,
matt
by fooman
Sat Dec 31, 2011 3:41 pm
 
Jump to forum
Jump to topic

Re: 3D surface modeling of a giant redwood trunk

A quick play with the Stratosphere Giant data. Still have not figured out textures that well.

The software has dedicated measurement tools (it is actually designed to measure the difference between a mesh and generated solid models, as a way of quantifying the accuracy of reverse engineering). The mesh as shown has a volume of ~1.5 mm 3 . It obviously reads the .ply data a certain way. Next stop, figure out the scaling required to get an accurate volume.

Cheers,
Matt


SG_1.jpg
by fooman
Tue Feb 07, 2012 5:27 pm
 
Jump to forum
Jump to topic

Re: Lake Champlain Valley and whopper cottonwoods

Hi All,

Just as a point of interest, this is the largest (eastern?) cottonwood (Populus deltoides ssp. monilifera) that I know of: http://register.notabletrees.org.nz/tree/view/210 . It is an old ornamental growing in the city of Hastings in New Zealand. It is often referred to as the largest deciduous tree in the country ( I think there is only 1 (small) native tree species considered deciduous)

Height: 138 ft
dbh: 128 inches - actually diameter at head height (1.9 m/75 inches) to get above some buttressing
circumference: 33.5 ft
spread: 111.5 ft
points: 568

It is nearing the end of it's life, but there are a few similar sized trees scattered around New Zealand. These were all planted in the late 19th century, as ornamentals, all originating as cuttings (or seeds?) from a tree brought in from England in 1852.

Another sibling of this tree was planted in the city of Tauranga in the 1860's. Known, rather erronously as "The Aspen", it was removed early last year (The tree in 1976: http://www.panoramio.com/photo/21383971 and being removed: http://econtent.tauranga.govt.nz/data/parks/images/aspentree_removal_digger_july2011.jpg ). It was about the same size, not quite as high as the Hastings tree.

Cheers,
Matt
by fooman
Tue Feb 14, 2012 9:46 pm
 
Jump to forum
Jump to topic

List of tallest tree species in New Zealand

Hi All,

Due to some free time recently (recovering from a nasty head cold), and inspired by Michael Taylor's recent update on New Zealand's tallest tree, I thought I would assemble an initial Rucker Index for New Zealand.

Notes:
1. Sources are BVP: Bob van Pelt; SS: Steven Stillett; MWT: Michael Taylor; NZNTT: New Zealand Notable Trees Trust register; Burstall: S.W. (Bob) Burstall, legendary NZ forestry mensuration expert; Dawson & Lucas: Recent textbook on NZ trees.
2. All but those from Dawson & Lucas are actual tree measurements. I had to revert to the general heights from Dawson & Lucas to include some of NZ's taller tree species for which there are no known highest specimens (e.g. the common canopy hardwoods such as tawa and the southern beechs) to get an R10 for the native tree species.
3. BVP/SS/NZNTT measurements are mostly laser based and reasonably contemporary. Burstall's measurements are more traditional (e.g. clinometer) and date from the 1960s to the early 1980s. Therefore his measurements are likely to be superseeded by more recent measurements, e.g. Michael Taylor's post mentioning that that Sillett and van Pelt measured Douglas Fir in NZ "close to" the height of the tallest mountain ash in NZ (80 m/264ft).
4. The list does not include tree species that were measured to be taller than the more recent measurements, but have known to have broken off or fallen, e.g. a 64 m Eucalyptus globulus that was measured at that height in 1961 but found to be living, but partially fallen against a hill 20 years later.

The Lists:

New Zealand's tallest native tree species:

nzrucker_native.jpg

New Zealand's tallest trees, introduced and native:

nzrucker_all.jpg


I am pretty sure there may be some taller exotic species (from Burstall) that may get into the R20 for all trees, boosting that a bit.

I did try to do everything as a BBCode table, but that option does not seem to work here, so sorry for the small text in the images.

Cheers,
Matt
by fooman
Wed Feb 15, 2012 11:40 pm
 
Jump to forum
Jump to topic

A couple of Giants in New Zealand

On a visit to Hamilton in North Island of New Zealand, I managed to visit a couple of trees, both introduced species, that are amongst the biggest of their species in New Zealand.

1. Awhitu Macrocarpa

The Monterey Cypress ( Cuppressus macrocarpa ) is known throughout New Zealand as "macrocarpa". While researching the location of a large pohutukawa ( Metrosideros excelsa ) on the Awhitu Pennisula just west of Auckland, I found references to a macrocarpa that was supposed to be the largest in New Zealand. While not native to the country, trees of the species do grow very large here - A tree in Golden Bay with 3 fused trunks was measured at 44 ft cbh, another single stemmed ornamental was measured at 40 ft cbh, and a tree in Tauranga was measured at 50.9 m (167 ft) tall. So a few months after I found references to the Awhitu tree, I flew to Auckland and drove the 100 miles or so to the park where the tree was located.

The tree measured up as being 23.8 m (78 ft) tall, a spread of 29.5 m (97 ft), and most impressively, a cbh of 14.55 m (47.7 ft), for a total of 675 points. This is slightly less than the American Forests champion (683 points) at Pescardero, CA (visible in Google Street view here: http://g.co/maps/tpswy ), but the Awhitu tree has a larger circumference (and is single stemmed). See http://register.notabletrees.org.nz/tree/view/963 for more details.

Awhitu small.jpg

Awhitu small 2.jpg

2. Newstead Gum

The Newstead gum is a mountain ash (Eucalyptus regnans), the species orginating in south east Australia, and currently the second tallest known tree species after the coastal redwood. Planted around 1878, it was regarded as New Zealand's talled tree (measured at 71.3 m / 234 ft) in 1964, when it was 86 years old. In 1968 Cyclone Giselle knocked the top off the tree, reducing the height. When the tree was last measured in 1999, it was 60.35 m (198 ft) tall, with a spread of 27.5 m (90 ft) and cbh of 12.68 m (41.6 ft).

The field the tree (and neighbouring mountain ashes planted at the same time) had recently been incorporated into a local reserve, enabling public access. I visited the tree in late 2010 to take some photos to submit to the New Zealand Notable Trees Register. Subsequent to that visit, I purchased a Nikon 550 Forestry to assist in my tree hunting addicition. Since no laser-based measurement of the tree had been performed, and it was literally just down the road from my sisters house, a family visit at Easter provided the excuse to try for a laser measurement of the height of the tree. The tree was found to be 62.6 m (205.4 ft) tall, the spread still at 27.5 m (90 ft) and an increase in the girth to 12.99 m (42.6 ft), for a total of 739 points. Even so, the Newstead gum is not the largest of it's species in NZ, there being a larger (in girth and spread, but shorter in height) tree near Dunedin in South Island ( http://register.notabletrees.org.nz/tree/view/640 ). Also near Dunedin is the tallest tree in NZ, another mountain ash, at 81 m (265 ft) tall as recently reported by Michael Taylor ( http://www.ents-bbs.org/viewtopic.php?f=50&t=3444 ).

The Newstead gum is not even the tallest tree at its location these days - A quick scan of the surrounding trees showed one at 64 m (210 ft) in height, and a recently fallen trunk at just shy of 60 m (197 ft) to a broken top. More information is at http://register.notabletrees.org.nz/tree/view/588 .

newstead small.jpg

newstead small 2.jpg

Cheers,
Matt
by fooman
Mon Apr 09, 2012 1:24 am
 
Jump to forum
Jump to topic

Re: 'Big Bob' - a giant eucalypt - Queensland's tallest tree

Hi All,

Although the various articles don't state the species, it is probably a Blackbutt - Eucalyptus pilularis - one of the larger Eucalyptus species in the state.

As Kotua pointed out, there is not a lot of information about tall trees in Queensland. I've spent a bit of time in the state for work - we have an office at the Gold Coast, close to the NSW border, and a number of clients spread throughout Queensland. Queensland itself is a large state - slightly bigger than Alaska, almost three times the size of Texas, spreading from the tropics (10° S) to the border with NSW at 29° S, 1300 miles from top to bottom. West of the Great Dividing Range, it is dry and arid, to the east it moist, and depending on the latitude, tropical or temperate.

Queensland has a number of interesting tree species - for me they are mostly in the Araucariaceae:

[*]Three species of Agathis - A. robusta (Queensland Kauri), A. microstachya (Bull Kauri) and A. atropurpurea (Blue or Black Kauri)
[*]Two species of Araucaria - A. bidwilli (Bunya Pine) and A. cunninghamii (Hoop Pine).

Agathis atropurpurea and Araucaria cunninghamii are supposed to get to 60 m (200 ft), with Agathis robusta, Agathis microstachya and Araucaria bidwilli getiing anywhere from 40 to 50 m tall (130 to 165 ft).

Araucaria from Norfolk Island (Norfolk Island Pine) and New Caledonia (Cook Pine) are also exceedly common.

The other cool tree species I have seen in QLD are:

[*]Queensland Bottle Tree - it is similar to a miniature baobab tree (Australia does have a baobab species, but the bottle tree is unrelated).
[*]Morton Bay Fig - A huge fig species.

Some photos, including a few not from QLD!:

robusta (960x1280).jpg

bunya1 (1280x524).jpg

hoop pine (852x1280).jpg

Cook pine (852x1280).jpg

araucaria (1280x960).jpg

bottle (960x1280).jpg

There are some nice specimens documented at the Australian Register of Big Trees, including:

[*]Bottle Tree: http://www.nationalregisterofbigtrees.com.au/listing_view.php?listing_id=463
[*]Bull Kauri: http://www.nationalregisterofbigtrees.com.au/listing_view.php?listing_id=121

And finally, on my first visit to Australia, I drove through the SE Queensland town of Blackbutt, named after the tree, and was greatly amused by name of the local gallery, as seen in Google Street View:

http://goo.gl/maps/xUj44


Cheers,
Matt
by fooman
Tue Sep 11, 2012 6:41 pm
 
Jump to forum
Jump to topic

Re: Bushwhack Hits Paydirt

Don,

That picture has wide angle lens distortion. After you get above the root swell on the "Sugar Tower", the trunk is cylindrical and very high to the first branch.

Michael

Michael-
The camera angle I'm guessing imparts more taper than there actually is...I'll bet that the bole is amazingly cylindrical with very little taper until after at least the first branch?
-Don

Hi All,

There are two methods for correcting for perspective distortion created by objects receeding from the camera:

1. Use a camera with built in perspective control, such as a view camera (the old-fashioned bellows type) or a camera with a perspective control lens, also known as a shift lens (see http://en.wikipedia.org/wiki/Perspective_control_lens ). This method is rather expensive, as most view cameras or PC lenses are not cheap!

2. More common these days is to use image processing software to perform perspective, or keystoning, correction. It can be simple manual distortion of the image, or semi-automated, using software such as Photoshop or DxO Optics - such software also use calibrated lens corrections to help correct all sorts of distortion. An example of such correction, using the freeware Gnu Image Manipulation Program (GIMP) is at http://constantphotographer.blogspot.com/2011/07/perspective-control-with-gimp.html .

The computer I use came with a older version of Photoshop Elements, so PC control is fairly easy. On the assumption that most of the trees are vertical (except for the small one to the left), I just had to adjust a slider until most of the trees are vertical. This isn't perfect, as the figure at the base shows some distortion, but it does provide a better representation of the bole of the tree. See attached images.

Cheers,
Matt

sp_perspect1.jpg

sp_perspect2.jpg
by fooman
Sun Oct 14, 2012 4:11 am
 
Jump to forum
Jump to topic

Re: The tallest tree of Europe?

All,

Just some more info with regards to the forest at Whakarewarewa (including the memorial redwood grove):

- Rotorua does get frosts, down to -7 °C. Records show 53.5 days of ground frost on average. Rotorua is one of the few inland cities in NZ, and is actually at a little bit of an altitude (~300 m asl). This does give it hotter summers and colder winters than cities of comparable latitude near the coast, or at lower elevations.
- It is approxiately 44 km to the nearest coast (NE of Rotorua), approximately 130 km from the west coast (the prevailing wind direction in NZ). The prevailing wind direction in Rotorua appears to be W to SW
- The forest is approximately 3 km south of Lake Rotorua (80 km 2 )
- The forest is located on a north (sun) facing slope of approximately 200 m local relief. The grove is located at the foot of this hill.
- There is considerable volcanic activity in the area (Lake Rotorua is a flooded caldera, approximately 250 000 years old), with a few feet of ash-rich soils from large eruptions (most recently Mt Tawawera in 1886)
- And most notably, the grove is 1.3 km east of the Whakarewarewa geothmermal area, which contains NZ's most productive remaining geyser field. Drift from the geothermal sourced clouds is quite common, and has been noted as a potential source of "foggy" conditions for the trees.

I've been wandering through the grove on a number of occaisions, most recently during a very short visit during my families summer holidays - early one morning I managed to limp around the grove track with an injured foot, Nikon 550 in hand, to see what I could find - I was after a 67.1 m tree reported by Steve Sillett. Getting heights of trees was problematic in most of the grove: secondary growth of ~30 to 40 m obsured the tops of the trees planted in 1901. There is a small swamp/spring which looked and smelt a bit geothermal. Tops of trees were visible and the surrounding trees were level with the boardwalk briding the swamp. On one edge of this opening, there were a number of trees exceeding 60 m, including one of 68.7 m (225 ft), 202 cm dbh. I have since learned from the administrator of the NZ Notable Trees Trust that Bob van Pelt measured 4 or so trees around 68 m during a visit in 200(9?). He also measured Douglas fir at around 55 m ( a large stand to the NE of the redwood grove), and a number of specimen trees planted at the nearby foresty research institute (Scion), inluding a Torrey pine at 43 m tall.

Now, it could be said that the local conditions at Rotorua are great for redwoods, and conifers in general. Having said that, during the same trip I managed to run the 550 over a small planting (~1 ha) of redwoods at a town called Te Kuiti, 100 km west of Rotorua. I had always wondered about the height of these Te Kuiti trees. I found that the ones at the edge of the grove were 50 to 55 m tall. I managed to measure one at ~ 62 m a few metres in from the edge. I have no history for the Te Kuiti grove, and could make no comment, other than a quick look inside, from the roadside showed that the stand was actively managed (trees were numbered and cbh levels were marked) and were not as large as the Rotorua trees, so may have been planted some time after the Rotorua trees (I suspect ~ 1920's as a lot of introduced conifer species were planted around that time in the central North Island).

Cheers,
Matt
by fooman
Sun Feb 10, 2013 6:32 pm
 
Jump to forum
Jump to topic

Re: Getting serious about big tree lists

Thanks, Matt! The format of the database seems to be very good. The only downside I noticed during my short visit is that all the measuring methods (laser, clinometer, estimate etc.) are accepted in the height record lists. I also compared the results with the height record lists you compiled (viewtopic.php?f=50&t=3710#p15294) and many important trees appear to be missing from the notabletrees.org.nz .

Hi Kouta,

As far as I am aware, the NZNTT register was set up with a considerable amount of legacy information from written records. The requirement for various height measurement methods is a reflection of that. The register itself is not just for trees with superlative dimensions, but also significant trees for cultural reasons.

At the moment there are approximately 1000 trees on the register, with around 50% being verified (i.e. legacy information confirmed from contemporary reports, or new trees entered into the register). There are a lot more trees in NZ deserving of inclusion, but tracking them down takes time and effort! A lot of the information comes from the records of S.W. "Bob" Burstall - he recorded the locations and dimensions of approximately 5000 trees from the 1960's to the early 80's as part of his work with the (now defunct) NZ Forest Service. 8 or 9 unpublished mensuration reports by Burstall were written, covering NZ trees by geographic location. Few copies of these reports exist, and are not readily available to the public. I have seen a copy of one in a local library. The reports were summarised in a more accessible form in the publication "Great Trees of New Zealand" in 1984. The lists were reviewed in the early 2000's as part of a foresty course at a polytechnic. That work has been summarised in the following presentation:

http://www.trees.org.uk/aa/documents/amenitydocs/aa_amenityconf_tue5_Rob_Graham_2011.pdf

Even the above presentation has inaccurate measurements. The measurements taken by Bob van Pelt in a couple of jaunts to NZ are available to the NZNTT, but following these up will be a series of expeditions! Ther other thing to note, is that I am sure you could go to anywhere in Whirinaki, or Pureora forests and with a few days hiking, be able to completely redfine top 10s for the largest podocarp species in NZ - that is probably what BvP did!

Just to give you an idea, the Gymnosperm Database has the following information for the tallest Kahikatea (NZ's tallest native tree):

The tallest known native tree in New Zealand is a kahikatea in the Pirongia Forest Reserve, 62.7 m tall when measured in 1996/7 by a Department of Conservation ranger (emails from Sonia Frimmel, 2012.05.22; and Bruce Postill, DoC, 2012.06.18). There are unconfirmed reports floating about the Web (as of mid-2012) of a 66 or 67 m tree, also in Pirongia. Older tall tree reports include one 229.3 cm dbh and 56.4 m tall, on private land near Matirangi Forest in the Taranaki region (R. Van Pelt email 2009.04.14). Another very tall tree, 220 cm dbh and 55.1 m tall, was measured in the Pirongia Forest Reserve (R. Van Pelt email 2003.01.27).

The three seperate trees at Pironga (62.7m, 66-67 m, and 55.1 m) are, I my opinion, likely to be the same tree! There is a specific track (about 8 hours hiking return) to a particular tree in Pirongia Forest, and it is said to be NZ's tallest native tree. Of these measurements, I would trust BvP's the most, even if it means there is a taller Kahikatea somewhere else. There is a video on youtube of a climb on the tree at http://www.climbeverything.co.nz/category/blog/ (no tapedrop however). Verifying the tree for entry would be a bit of an expedition for me, but I will do it some day (maybe Easter: I will be ~3 hours drive away from the forest, so it will be a long day to do so). That is for just one tree, and I am only a semi-enthusiastic amateur, with some restrictions on travel (i.e. family and work commitments).

The height records I compiled do need updating. I have some updated measurements of trees, plus some more information on heights of particular species from other reference books.

Cheers,
Matt
by fooman
Sun Feb 17, 2013 6:35 pm
 
Jump to forum
Jump to topic

On points calculations and large cottonwoods.

As previously mentioned, there are some large specimens of Populus deltoides in New Zealand, planted as introduced specimen trees over a hundred years ago.

A recent addition to the New Zealand Tree Register of notable trees is a large cottonwood called the Waiohika Poplar ( http://register.notabletrees.org.nz/tree/view/1123 ). The raw dimensions are larger than the (now declining) NZ champion, the Frimley Poplar ( http://register.notabletrees.org.nz/tree/view/210 )

Frimley Tree: 138 ft high, 112 ft spread, 33' 6" cbh
Waiohika Tree: 141 ft high, 157 ft spread, 33' 8" cbh

The Waiohika tree would have a points score of 585 vs 568 for the Frimley tree, but for a small secondary stem (pictures are availble at the above links) disqualifiying it as a single stem tree.

Anyway, this got me thinking, and I wonder if anyone has suggested the following modifcation to the points calculation for multi-stem trees where the largest stem girth is not known:

points = height (ft) + spread/4 (ft) + [cbh/n] (in), where n is the number of stems at breast height.

This would not discount trees with execptional heights, or spreads, but modify the bias in the formula towards girth, such that it accounts for large girths influenced by multiple stems. I do see it as an approximation when, for example, the largest stem girth is not measured and subsituted into the formula. But then, do you use the height and spread for that single stem in the points calculation?

Such a modification seems obvious, so I am curious if anyone has suggested it before? In the example above, the Waiohika tree has 383 points, rather than 585. Still a big tree, just not a champion. A measurement using the largest stem would increase this score, which does point out such a modification is still an approximation of an actual score (but more accurate than a score of 0!)

Cheers,
Matt
by fooman
Thu Aug 29, 2013 6:30 pm
 
Jump to forum
Jump to topic

Largest Eastern Cottonwood in NZ (and the world?)

Hi All,

A few years ago I made a quick note about the Frimley Poplar, the largest deciduous tree in New Zealand. I finally managed to spend some time in the area and managed to take a few photos of this impressive tree.

Measurements, as of 2011 ( http://register.notabletrees.org.nz/tree/view/210 ):

Height: 138 ft
dbh: 128 inches - actually diameter at head height (1.9 m/75 inches) to get above some basal flaring
circumference: 33.5 ft
spread: 111.5 ft
points: 568

The points total is 3 more than the US national champion P. deltoides var deltoides ( http://www.americanforests.org/bigtree/populus-deltoides-ssp-deltoides/ ), 38 more than the US national P. deltoides var. monilifera ( http://www.americanforests.org/bigtree/populus-deltoides-ssp-monilifera-3/ ) and 70 more points than the US national champion P. deltoides var. wizlesni ( http://www.americanforests.org/bigtree/populus-deltoides-ssp-wislizeni/ ). Not as many points as the US national chamption Fremont Cottonwood ( http://www.americanforests.org/bigtree/populus-fremontii-ssp-fremontii-3/ ), but that tree, and all the other US champions above are all multi-stem trees.

It is summer here at the moment, so the tree was in full leaf. It is past its prime, with a large hollow (and fire damage), but still a very impressive specimen.

One of the highlights of a (rather too short) summer vacation.

Cheers,
Matt

DSC03449_small.jpg

DSC03444_small.jpg

DSC03446_small.jpg
by fooman
Wed Jan 01, 2014 4:00 am
 
Jump to forum
Jump to topic

Re: Largest Ohia on Maui?

The Metrosideros species we have here in NZ have numerous variations of trunk forms, with aerial roots all over the place. The largest, M. robusta, or Northern Rata, is most commonly a hemi-epiphyte, with a large trunk formed from roots descending from, and eventually surrounding, a host tree. Similar to strangler figs. Largest recorded was approximately 60 ft in girth.

The pohutukawa, M. excelsa, often has mats of aerial roots that can often form pseudo-trunks from branches. It is reasonably similar to the Ohia, although a bit larger: up to 30 ft in girth, and 150 ft spread.

So, my guess is aerial roots, not vines (although there are also Metrosideros vines as well!)

Cheers,
Matt
by fooman
Mon Feb 24, 2014 2:05 pm
 
Jump to forum
Jump to topic

Re: redwoods as plantation trees

Found some more information on Redwood plantations in NZ. A California forestry company, which has set up redwood plantations in NZ has surveyed an experimental planting from the 1920's, located in Taumaranui, NZ. 10 acres in size, the average stem height is 216 ft after 90 years growth. This is approximately 20 ft higher than the older Whakarewarewa grove in Rotorua. They also give a stand volume of more than 300,000 board ft per acre. The stand was (is?) unmanaged. Information is given at http://www.soperwheeler.com/company-updates/taumarunui-redwood-reserve-2/

This planting is on public land, as part of a local reserve. Definitely on the list for a visit, especially to see if individual trees are taller than the tallest in Rotorua - and therefore the tallest redwoods outside their natural range.

Cheers,
Matt
by fooman
Thu Oct 09, 2014 6:41 pm
 
Jump to forum
Jump to topic

Re: redwoods as plantation trees

Hi Guys, just a few comments about redwood growth as planted in NZ.

The most famous (coast) redwood grove at Whakarewarewa was planted around 1904. The growth rates are documented at http://www.nzffa.org.nz/farm-forestry-model/resource-centre/tree-grower-articles/tree-grower-february-2007/rotorua-redwoods/ . After 50 years, the trees were on average ~ 130 ft high and 3 ft in diameter. Now, around 110 years after planting, the trees average ~ 200 ft high and 4 1/4 ft in diameter, with the largest around 7 ft in diameter. The tallest is around 72 m (236 ft). See http://register.notabletrees.org.nz/tree/view/1208 and https://www.youtube.com/watch?v=--9j-OA5c3w

Some nearby trees, in the grounds of a forestry research organisation, were felled for safety reasons in 1997. Largest was ~ 6 1/2 ft in diameter. See http://www.nzffa.org.nz/farm-forestry-model/resource-centre/tree-grower-articles/tree-grower-february-2007/harvesting-and-marketing-some-pruned-redwood-giants/

It has been mentioned that the timber from the redwoods was found to be quite brittle compared to timber harvested from trees in its natural environment, perhaps due to its quick growth. Similar findings for plantation Pinus radiata with exceptional growth (210 ft in 60 years) has also been noted.

The largest giant sequoia in NZ was planted in the 1860's and is currently 4.6 m (15 ft) dbh, influenced by the open growth and ~ 150 ft tall. See http://register.notabletrees.org.nz/tree/view/1160

Tallest known in NZ is 185 ft, planted around 1890, see http://register.notabletrees.org.nz/tree/view/613 .

Cheers,
Matt
by fooman
Mon Oct 06, 2014 5:28 pm
 
Jump to forum
Jump to topic

Re: Extending tree diversity comparison to Southern Hemisphe

Hi Don,

A quick perusal of Dawson & Lucas' "Native Trees of New Zealand", using a criterion of tree >= 5 m, there are approximately 210 tree species in NZ (I lost count a bit towards the end) and the outlying islands (including subtropical Kermadacs to Sub- Antarctic Auckland Islands). This includes 18 conifer species (2 more are shrubs), 6 tree ferns, and the rest angiosperms (including one palm, a number of palm-like cordyline and dracophyllum species) as well as more normal looking trees. Large genera include 25 Coprosma tree species (plus another 30 shrubs), 23 Olearia trees (plus 9 shrubs), 15 Pittosporum (plus 6 shrubs) and 12 Pseudopanax.

The book had more species than above, but they were described as "shrub to small tree" less than 5 m. Their criteria for a tree was a woody species more than 4 m in height, with a single trunk or substantial woody limbs. The book doesn't have a numerical breakdown, but the vast majority of species are 5-15 m tall. There are approx 35 tree species considered emergent or canopy trees (20+ m). The rest are sub-canopy.

I do remember reading a paper about NZ tree species height evolution. Most species evolved from shrub-like plants, and there was little competition for light. The emergent species didnt block a lot of light so height was not required as a trait.

The book states in total that NZ has ~2300 species of angiosperms, conifers and ferns in 268 000 sq km (~100,000 sq miles), 80% of which are endemic.

Cheers,
Matt
by fooman
Mon Jan 12, 2015 5:49 am
 
Jump to forum
Jump to topic

Re: Large tree falls over in rain storm in Nelson, New Zeala

Probably not irrigated, as Nelson gets around 1000 mm (36 inches) on average each year, distributed evenly throughout the year. Great region for horticulture.

That particular storm was the tail end of Cyclone Ita.

Cheers,
Matt
by fooman
Thu May 07, 2015 5:35 am
 
Jump to forum
Jump to topic

Re: Using Google Earth like Lidar

Using Google Earth Pro (recently made free to use by Google), you can define a polygon at a set distance parallel to the ground. With good 3D data, a height measurement of +\- 1 m is possible. Sometimes the tops of trees are not captured by the method used to get the data, so the height is a minimum, rather than a "actual". A good screening tool. The trees you have shown would be able to be measured reasonably accurately.

Apple's Flyover 3D data is of better quality at the moment, but there is no easy way to query the data.

Cheers,
Matt
by fooman
Sat Jun 06, 2015 3:25 pm
 
Jump to forum
Jump to topic

Re: Using Google Earth like Lidar

I had a play with GE Pro on the trees in the original post. The 3D data hasn't captured the true tops of the trees, reading a bit low. But it is still good for finding relative heights in groups of trees.

Cheers,
Matt

GEPro polygon redwood.jpg
by fooman
Wed Jun 10, 2015 6:22 pm
 
Jump to forum
Jump to topic

Re: Kauri trees in New Zealand

Hi Rand,

Kairaru was always described as a single-trunked tree by those who saw it living, and after it had been killed by fire in the late 1880's. Large Kauri are invariably single stemmed - multi-stemmed examples tend to have skinny, well seperated trunks. The fact that Kairaru was found by NZ's surveyor-general (at the time) and was officially measured by a forestry ranger soon after meant that its measurements were considered reliable.

Note that the kauri industry, the total height was not held to be important. The most important measurements were the diameter, and the merchantable height of timber to the first branch, plus any logs above it. In terms of timber volume, the methods used (directly measure cbh, mechantable height, estimate taper - almost none in most kauri) gave a timber volume that underestimated the actual volume by around 3-5% according to a paper from the 1940's which compared that to tape wraps up the trunk. The wood volume in the crown was ignored, even though it may be up to 50% of the tree. Bob Van Pelt measured Tane Mahuta at ~516 cubic metres total volume, with 255 cubic metres in the stem, the remainder in the crown.

There are are few other trees reported to have a larger girth than Kairaru - one in Mercury Bay was measured twice - one measurement was ~74 ft, the other 78 ft in circumference. One was taken after the tree had died (in a fire?) around 1850.

More recently, a fallen tree in Warawara Forest was found in the 1970's during the last of the forestry operations there. The hollow trunk, partially collapsed, would have been ~24 m / 78 ft in circumference when fully round. A small tree, with ~70 growth rings was found growing on the stump, so the tree had been dead for at least 70 years. The only wood remaining was ~ 2 or 3 ft of sapwood (kauri is quiet resistant to rot due to the high resin content of the timber), and I think some samples of the trunk are at the Kauri Museum at Matakohe. In a conference presentation that I attended in 2014 by Dr Peter Waddell, he noted that samples from the remaining timber had very strong medullary rays in the timber - typical of Kauri growing in swampy conditions, and approximately 1800 growth rings (yes, 1800) in the outer two or three feet of the trunk. Maybe not annual rings, but certainly enough to tell that the tree was very old when it fell.

There are records of a number of trees around the 20 m circumference of Kairaru - I have a list on my computer at home, but none "official" - most were taken by forestry workers as they cut through the timber. In terms of the existing trees, 13 to 15 m cbh was notable, but not unusual before the early 20th century.

If you want get an idea of the size of the kauri trees, doing a search on old photographs does give an idea of the trees in their prime: Kauri forestry was a major industry between the 1860's up until the 1920s - very similar to the redwoods in California. I will attach a few public domain photos down thread.

Cheers,
Matt
by fooman
Sun Jul 26, 2015 8:31 pm
 
Jump to forum
Jump to topic

Re: Kauri trees in New Zealand

Kopi

EP19390526.2.32.1-a1-700w-c32-1074-529-2565-3261.gif

Kopi was considered to be the "best" combination of height/girth (~ 13.5 m cbh) and height of trunk before it fell in 1973. Picture taken in 1939. A colony of rare native bats was found in the hollow trunk, which still can be seen today.
by fooman
Sun Jul 26, 2015 9:16 pm
 
Jump to forum
Jump to topic

Re: Kauri trees in New Zealand

The Glasgow Tree

JTD-08F-03819_access.png


JTD-08F-05174_access.png


One of the largest trees in the Waitakere Ranges, west of Auckland, this was named after the Earl of Glasgow. Reported as between 44 to 52 ft cbh, Burnt down in 1898.
by fooman
Sun Jul 26, 2015 9:06 pm
 
Jump to forum
Jump to topic

Re: Kauri trees in New Zealand

AWNS_19320210_p031_i001_x.jpg

Toronui - Fell in a storm in 1977 - At approximately 15 m cbh, it was considered the largest Kauri (by merchantable volume) at around 286 cubic metres/ 10,000 cubic ft in the trunk. The tree was hollow however. Note regular incisions in the trunk - this tree was a victim of "gum bleeding" where the resin (Kauri gum) was collected, being quite valuable in the late 19th/early 20th century.

The photograph was taken by Tudor Collins, a forestry worker turned photographer, and published in the 1920's (and so, according to NZ copyright legislation, is in the public domain).
by fooman
Sun Jul 26, 2015 8:47 pm
 
Jump to forum
Jump to topic

Re: Pinus radiata, the Monterey pine

During an extended trip to New Zealand 16+ years ago I purchased a book titled "The Natural World of New Zealand: An Illustrated Encyclopedia of New Zealand's Natural Heritage," by Gerald Hutching...

The included photograph is some of the Kinleith Forest plantings. The peak in the background is Pohaturoa, a volcanic dome on the banks of the Waikato River, near the Atiamuri Dam. The trees on Pohaturoa have been harvested, and will not be re-planted, as the peak has historical significance as a Maori fortification. Only 2 or 3 miles away is the Owen Road permanent sample plot, where Tree 73 was (and maybe still is) the tallest P. radiata ever measured, at 64.2 m / 210 ft in the early 1980's at around 55 years age. The tree was still extant in the mid-1990's but there is no current record of it.

The below graph is from a review of plantation forest in NZ and shows the measured average tree height (MTH) in m, versus plantation age for the permanent sample plots of the species scattered over the country.

radiatagrowthnz.jpg

The first trees of the species were planted in NZ around the 1860's and were found to have such good growth that the vast plantations of the 1920's were mostly P. radiata. There are a couple of massive specimen trees around Geraldine in the South Island, both planted around 1859. One tree at Mt Peel Station, said to be the first planting in NZ, is 148 ft tall and 33 ft cbh (influenced by low branching), and can be seen at http://register.notabletrees.org.nz/tree/view/1312 . Nearby on the outskirts of Geraldine is the Grey Pine ( http://register.notabletrees.org.nz/tree/view/1008 ), at 156 ft tall, and 29 ft in girth, with better form than the Mt Peel Tree.

Grey Pine 2.JPG

Grey Pine 1.JPG

Cheers,
Matt
by fooman
Sun Feb 28, 2016 5:41 pm
 
Jump to forum
Jump to topic

Re: Pinus radiata, the Monterey pine

Hi Rand,

I think a lot of the earlier plantings were for novelty or botanical collections. Quite a few of the large specimens of exotic (non-native) trees we have in NZ are in formal gardens or collections, e.g. the Mt Peel Pine is just one of a number of conifer specimens adjacent the old homestead. Nearby is a Douglas fir, again planted around 1859, measured at 69.6 m / 228 ft by BVP in 2013. When seeds became plentiful, it was found both Monterey Pine and Monterey Cypress ( C. macrocarpa ) grew quickly, and they were used as shelter-belts for livestock on the farms being developed by the European settlers.

A few decades after the original plantings, some research was done from the late 1800's and the early 1900's on trees for plantation forestry. The famous redwood grove at Whakarewarea in Rotorua (with trees up to 71.5 m /235 ft tall at around 110 years age) is one example of a research plot, planted in the early 1900's.

The results were that P. radiata gave the best yield, followed by Douglas fir. The large scale plantings of the 1920's were undertaken as a depression-era work scheme, especially on the "unproductive" scrubby pumice soils of the central North Island, that formed the then largest plantation forests in the world (e.g. Kaingaroa Forest). Most were in P. radiata, some in Douglas fir.

Cheers,
Matt
by fooman
Sun Feb 28, 2016 7:59 pm
 
Jump to forum
Jump to topic