Yes, I have some views!

Assuming you can get close to what you're cutting, you can do away with the first 4. I'll get back to this in a minute.

Leave chainsaw work to a trained professional - you can't imagine how easy it is to do serious, permanent damage to yourself with one of those.
Consider a few facts:
A chainsaw basically has a moped engine on it, however the difference is that its 'at work' speed is between 10 and 12,000 revs.
It is directly driving about 50-odd razor sharp chisels which are about 1/4 of an inch wide.
If you are not careful (and sometimes when you are) all of that destructive power can be redirected back at you before you are aware of what is happening - literally quicker than you can blink.
When that chain hits you, it doesn't cut you - it removes a 1/4 inch strip from you.
I have seen the damage it can do - please don't allow it to happen to you.


Back to the first 4 options:
Get yourself a Silky Fox 'Gomtaro' pruning saw.  I like the 300mm size - the longer the blade, the fewer strokes required.
They are not cheap - £40 or so but they are incredible tools.  We have a couple and I use them for all sorts of jobs, including woodwork and DIY.  They are razor sharp and cut on the pull, rather than the push like a traditional saw.  It will cut a branch as thick as your thumb in one or two strokes.  It will make an amazingly clean cut with an almost planed finish - hence the reason for my using it for DIY.

The make a huge range of sizes and types of saw, including a range of pole saws for high pruning and several folding models.  I prefer one with a fixed blade.
To illustrate the efficiency of the things, when I used to sell Christmas trees, I would recommend to customers that they saw a disc from the base of their tree in order to make a fresh cut to allow it to take water up.  The odd customer would ask us if we could do it for them and if there were two trees to do at he same time, I would often have fun by giving one of my staff a race to see who could cut their tree first - him with a chainsaw and me with my Silky Fox.  The deal was that on the word "Go" he had to start his saw.  If the saw was cold, I would nearly always finish my tree before he could start it.  If the engine was warm he would usually, but not always, win.  

Thanks Chris

I'll try the one we have and then upgrade to a Silky Fox by the sounds of it.

I have a couple of silver birches that are at around 45% and another unknown tree to me about the same.
Trunk varies from about 6" to 10".

I'd like to keep whatever I can.
Can I cut the trunks with a Silky Fox ?
Is it a good idea to leave a leaning trunk to regenerate, say 6' long from the base or cut at the stump - or other !

Yip,I'm with ChrisB here. Chainsaws are lethal. A good quality handsaw,even at £7 is better. A decent axe and felling the tree properly is great.

Tell you what as well - post an ad on gumtree for free firewood if they take the tree down and you may be surprised at the response. Look in the freebies section on gumtree for firewood.

Basic tools for gardening around my way are of the safety first variety( to big and not agile enough for messing about on ladders etc)
Pro tools
#1 Digger or back hoe
#2 Dumper or Forklift with cage
#3 Long lengths of rope
#4 Chainsaw (if qualified, seriously) or I found a handsaw or one of the electric jobbies Black & Decker Scorpion is cheap and effective saves a bit of effort
#5 Mate(s) These are useful for laughing at your efforts and giving advice when you least expect it plus you can need them to take the strain on a rope when the tree is coming down in their direction
I know those of you with small suburban gardens may find some of this a bit ott but it does make it all a bit of a lads hour out and gets the job done quickly and tidied away with more time to go to pub to discuss the collective mornings work!

I've got a moped engine on a strimmer, a brush cutter, a hedge trimmer and an extending tree lopping chainsaw attachment.
It's great from the ground.
If you are good with tools and have common sense it's not rocket science. Right gear, right approach, read up, practise, take your time.
It would not do thick stuff like tree trunks though.

For that use a bow saw.
Stump grinding - er get someone in:)


For up the tree stuff those hand saws are great. Don't want to be trying to lug heavy equip up trees and use it...