Pruning in New Zealand

[Ernie]

Here are some shots of our 12 year old pines.  We (Alf) prune to 10 meters using a ladder and 3 uni-steps.  The saw is a Stihl 020T, very light high revving and powerful, with a bar length restrictor  perfect for the job.  We are planning to mill them at 27 years and hope that supplying clear lumber 8 to 10 meters long will gain us a premium as the local "Big" sawmills can only cut to 6 meters.

Hope you like the pix



climbing the first uni-step



Alf on the second uni-step



Alf on the last uni-step and ready to start



Hard at it on the final prune



The job is done



A uni-step



Enough green crown to give good growth for the next  15 years.



There are more pix in my gallery under "Pruning in New Zealand" if you are interested.

[Ianab]

And yeah... It is hard work 
 

[maple flats]

Doesn't look like fun, how about an easier way. How would my climbing tree stand work as long as I don't slip and saw the stand?

[rebocardo]

I just realized how and why you use the steps and such, no spikes or claws to destroy the bark or wood since you are spending so much time on pruning for clear wood 20+ years down the road.

To think some people pay a gym to use a cardio exercise machine. Its like getting paid to exercise 

[sawmillsi]

Ernie,

As an Australian I can't beleive that ewes guys prune your trees - we don't (but thats why we have to buy our clear pine from ewes).

Got a question - are you pruning to leave a percentage of the canopy left or to a certain height (and has that height been worked out to leave a certain perentage of canopy left)?

I was taught at uni that there is a fair bit of thought that goes into this kinda thing - too much for us simple ozzies eh!

Si

[Ernie]

Si

You Aussies may know nothing about pruning but some of you sure can swing the willow, cleaned us out 5 zip in the one day cricket; still there's the 5 day tests still to come, it'll be our turn then .

My son Alf is the silviculture expert, I know he leaves a certain percentage green crown but what it is, I haven't a clue, it is only 6 am now but when he gets up, I'll find out and let you know.  We aim for an annual increase in DBH of 1.5 to 2 inches.  Like every good teacher should treat each kid as an individual and teach to his/her strengths and abilities, Alf treats each tree on its merits and does a variable prune doing some each year and leaving others to catch up.  We aim for a pruned height of 10 meters, single leader with the minimum possible DOS.  He got really *pithed when I grazed under the trees with cattle too early and  stuffed up a few with bark stripping.  I'll let you know planting and final spacing later.

You should nip over and cast your eye around some of the NZ forests.  Now that Virgin is making the trans tasman flights, it's pretty cheap to get back and forth.  We go over to Brizzy every now and then to see our grand daughter, and her parents of course.  How far are you from there?

Ernie

[Ernie]

Si

Alf is up and has informed me that the % green crown varies with each tree, the main criterion is to leave adequate green crown to maintain growth rate, ie smaller trees = more green crown.  never go to less than 1/3 green crown.

 In commercial pruning ie: the whole block done in three lifts to 6.5 meters; first lift at 4 years to (depending on the regime) 3.5 meters GC or 1/2 tree height up to 2.5 meters. At 6 years(medium prune)  to 4.5 M leaving 3.5 M GC.  Final prune at 8 years to 6.5M leaving 4M GC.  In ultra high prune (8.5M) leave 4.5 M GC usually done at age 10 or 11years.

 Thinning from an initial spacing of  850 SPH to can happen in either one or two stages either after medium prune to 600SPH then after final prune to 350SPH or in as a  single thinning after high prune to 350 SPH.  There are many variations but these are the most common.  All thinnings are to waste to avoid damage to the final stand from dragging the thinnings through the forest.  As there are thinnings lying all over the place  a 2 stage thin causes problems getting through the block, thinning is most commonly done in one go after high prune.  Since most blocks are only pruned to 6.5 M,  in three lifts, this is the most common regime used in NZ.

Personally, Alf prefers to plant 1200 SHP to give a better selection when pruning.  Some of our block would have been better planted this way particularly with the cattle damage which I caused .

We planted GF17-18 rated seedlings as our site is prone to strong winds and the higher GF rated stock is prone to blowing over as the root growth cannot adequately anchor the faster growing tops.  We felt that the sacrifice  in the  greater nodal length of the higher rated trees was worth the extra pruning required as a tree lying down is not really very worthwhile.  The same reasoning applies to cutting grown seedlings which make up a lot of the higher GF rated stock.

Thus endeth the Pinus Radiata silviculture lesson

Hope this answers your query

Alf and Ernie

[Jeff]

When is ALF going to join us Ernie?  Love to see him as part of the Forum.

[Ernie]

Maple Flats

Doesn't look like fun, how about an easier way. How would my climbing tree stand work as long as I don't slip and saw the stand?

What the heck is that
How about a pic?


Alf and Ernie

[Ernie]

Jeff

It's hard enough getting him out of the trees and away from the mill let alone onto the computer.  I'll see what I can do.

Ernie

[Furby]

Ernie,
Here's a couple of links to climbing tree stands.

http://www.ameristep.com/treestands/

http://www.northstarrtreestands.com/Arrowstarr.html

[Ianab]

Now I have this mental image of Alf up in the top of a pine tree, sitting in his padded easy chair lopping off branches with his feet up on the gun rest.
I think production would slow down tho, he'd stay up in the tree for a rest and maybe a little nap before coming down and going to the next tree 

[Ernie]

Furby

Thanks for the links, looks like a city fellers uni-step.

Ernie

[Ernie]

Yo Furby

That last pic on the North Starr site had us in fits of laughter  as we tried to picture a hunter stalking deer or wild pigs here in NZ with all that st-- on his back.  Not a pretty sight

Ernie

[Kevin]

We need to toss those steps in the garbage and get Alf gripping a good 16 strand climbing rope. 

[sawmillsi]

Ernie,

I have seen the pine forests between Rotorua and Taupo (was over last year giving the Peterson crew a hard time) and that is real impressive!

In Australia our pine forests would make you sick - take a quick drive just north of Brisbane (next time your over) and theres pine plantations either side of the Bruce highway around the sunshine coast.

I personally like well managed native forests over plantations (but I also think theres a place for every thing).

What would be the average internodal distance?

Do you try and prune before the branches get to a certain diameter (in Australia, we are looking at genetically modifying (or something - over my head) our Euc's so the braches are less than 25mm diameter when they drop off - leaves no marking in the timber)?

Did you's guys get your cricket players wifes to play cause they certanly played like a bunch of women!!! 

Good to see the Australian - New Zealander friendship crosses all boundarys execept sport!

Simon

[Ernie]

Simon

The son-in-law's parents live in Toowoomba and we drove out form Brisbane to have a gekko and a barbie of course.  Couldn't understand your pine tree growing system, are they all for pulp?  We saw all different stages of growth but had no idea the age of the trees.  I was totally unaware that pines were a desert species.  Could the land not be put to better use growing Jojoba or something like that.

Just wait till the tests and you will see NZ cricket at its best  .  Since NZ is such a green and fertile place with reliable rainfall and a climate that wont melt you if you step outside the AC we, in true Kiwi decency must let you guys have something so it is sport.

Ernie

[Ernie]

Kevin

As Alf is only half Canadian, I can't see him holding a 16 strand climbing rope in one hand and a pruning saw in the other swinging from tree to tree swiping branches off as he goes.  Maybe you should come down and give a demonstration some time.

 Always welcome.

Ernie

[Ianab]

Do you try and prune before the branches get to a certain diameter (in Australia, we are looking at genetically modifying (or something - over my head) our Euc's so the braches are less than 25mm diameter when they drop off - leaves no marking in the timber)?

The pruning is usually based on the diameter of the trunk. Thats the DOS (Diameter Over Stubs). The aim is to have all the knots etc in a small cylinder up the centre of the tree. This is normally low grade juvenile wood and the pith anyway. All the wood outside that cylinder should then be clear timber.

The higher GF seedlings that Ernie mentions have been bred / cloned / selected to give longer internodal gaps and smaller branches. But as he said they aren't as wind resistant as the lower GF trees. More important when you have small stands scattered around a farm.

Cheers

Ian

PS.. was there a cricket game played lately??

[farmerdoug]

When I was in college I watched a demo of a softwood tree trimmer.  It was a two man operation.  It had a small chainsaw vertically on a carriage than closed around the tree with wheels around the inside at an angle.  They would clamp it around the tree and set the desired height of trim and start it up and away it would go around and around the tree as it climbed.  It sure would make you dizzy just watching it.  It would cut off the limbs as it encountered them until it reached the desired height and then reverse and come down.  I am not sure if they are still around but two guys could trim a tree quite quickly with it.  I belive it was less than 5 minutes a tree but I was in college in the late 80's and things are starting to get fuzzy on some details.