The neolithic horsehead axe ,shown in reply # 73 is one i would pick for usage. That last horsehead axe looks also very apt for usage.  Ground celts seem to have a wide angle edge,probably long lasting,not so good in cutting. Knapped stone can be thinner,sharper,but i guess they could break,chip much easier.

jlasud, a fat pecked and ground celt works great for cutting green wood, the thinner ones would be used for light chopping and limbing up trees chopped down with the larger.  The smaller ones were carried for status, plus they worked great for hitting the neighbors in the mouth when they came calling in the middle of the night.  
 
There is a version that would be knapped out and then the blade edge would be ground smooth, it was much quicker to make but not as sturdy as the fully ground oned.  That type showed up just as the first bronze was being smelted so it only lasted for about a thousand years.

Actually, chopping down trees with a diameter from 10 to 15 centimeters required around 20 minutes using an amygdala  
Greetings,
Mauro.

It's the blue one here: http://slinging.org/forum/YaBB.pl?num=1291518865/9#9  
(part of the brain???).
Greetings,
Mauro.

Quote from Mauro Fiorentini on Aug 5^th, 2012, 3:15pm:

 
The Amygdala: http://en.wikipedia.org/wiki/Amygdala  

Quote from xxkid123 on Aug 5^th, 2012, 7:40pm:

 
Oh well, then I must say I've never used my amygdala for cutting down trees, but I once eat one, it was the brain of a calf. I also eat his tongue and his eyes which were the most tasty pieces of his head  
 
However I used my amygdala, the one made of flint, by helding it in my hand, without handle, just like a saw.
Greetings,
Mauro.

Bill,yea they also used "felling axes" as well as small hatchets,just like we use today,to fit the job.
I guess it's not SO time consuming than as one might think... If only today,they weren't any chainsaws ,just steel axes.
Deforestation would be less of a problem.

ground stone celts have been used successfully for thousands of years to take down some of the largest trees on earth. some of the post holes at stonehenge and cahokia, for instance, were over four feet in diameter. the celt differs from a steel axe primarily in the bit (edge) angle and is therefore used in a slightly different manner. where a steel axe chops wood in a '<' shape, taking out triangular chips, the celt chops in a '[' , hitting on two sides of the cut and blasting out rectangular chips. for every thing you ever wanted to know about celts, you should visit Larry Kinsela's site here... http://www.flintknapper.com/NEW%20AXE%20ME%20NO.htm   Larry is pretty much the authority on ground axes, having recreated and used them for decades.
 
Chris