Thinning out the Fir

[Karl_N.]

We had our woods logged ten years ago and we seem to be getting some good regeneration. I've noticed large clumps of firs averaging about 5-6' in height. When should I think about thinning them out and how much should I leave with a goal towards getting a small sawlog out of it later on during another thinning operation. The site is on a nice south facing slope up here in Northern Vermont? Anyone out there have an answer? Thanks in advance.
Karl

[SwampDonkey]

I've been involved in thinning thousands of acres of the stuff. 10 years of age is the right age to thin softwoods (6-7 foot tall). If it's mixed with hardwoods, I'de wait for the hardwood to get at least 15 feet. Spacing should be 6 to 7 feet between trees. Target density would be 2000-2500 stems/ha or 800-1000 stems/acre.  Leave hardwood dominated sites a little tighter, 1100-1400 stems/acre. I use a rope 3.57 meters (11.5 feet) long, and make a circle to count the post treatment density. I want 8 to 12 trees in softwood stands and 10 to 14 trees on hardwood sites. Get yourself a good thinning saw, like a Sthil FS450 and a couple replacement blades, a set and some files. Trees will be spaced the length of your thinning saw away from one another (roughly). Check with your local government and see if there is financial assistance for pre-commercial thinning. In New Brunswick, we spend $8M annually thining stands on private woodlots. Our rates are handy to $700/ha or $280/acre.

some math, it's easier in metric ;)

3.57 m rope to make a 40 m^2 sized plot, 250 of these plots fit on a ha.

how trees fit in a hectare of land if I average 8 trees per plot. 

8 trees x 250 plots/ha = 2000 trees/ha = 800 trees/acre

clear as mud eh? ;)

[Karl_N.]

Swamp Donkey, 
  Geez, thanks for the information. I'm always surprised by all the experts and their willingness to spread the wealth of their knowledge on this forum. Thanks again.
Karl

[Tillaway]

We usually thin down to about 250 to 350 TPA out here depending on species.  An argument can be made to go down to 200 ish or less.  Your next entry after PCT will be a commercial thin at the lower densities here. 

[SwampDonkey]

Tillaway, That's similar to coastal BC only I beleive their lower limit is 600/ha (242 st/acre) and the upper limit is 1200/ha (486 st/acre). Depends on species and plantability of the site.

[Tillaway]

Yep, should be the same as coastal BC.  There is a push to space them much farther apart and then prune.  We have been doing the commercial thinnings down to 120' BA, but new info leads us to reduce stocking down even more say 100' or 80' BA depending on site.