This is nearly always associated with bad drainage. Any more info you can give?

I have one that started going brown from the lower branches and are gradually working their way up the trunk it's about 25 yrs old , the top looks healthy I believe I read somewhere that it's natural for them to behave like that , I would like to know more about it as well , this one was here when we moved in ...

The monkey puzzle tree sits in an approx 30 square metre lawn and tends to absorb all the water (so the lawn always looks a little threadbare).
No drainage issues that I am aware of, rainfall always gets absorbed very quickly.

Mine was also here when I moved in 6 years ago, but in past 2 years seems to be going more brown ?
Top bit is still green, and some of the middle branches also green - but majority of lower branches all brown - is this normal ?
I have noticed some sap coming out of trunk near the bottom section of trunk - is this normal ?
Amy - Have you noticed if yours getting progressively browner each year ?

The tree stands in my front garden and is a lovely specimen - and has obviously been there many decades so I really hope it can survive - any help/thoughts much appreciated.
I have just joined this site June 2010.

I've just been out to have a good look at mine , hubby guesstimated it to be 25 feet tall , it is green and healthy looking down to about half that height the lower branches have individually turned brown each year , there's two there now that have turned brown , we usually saw them off , and yes there is some sap in odd spots coming from the trunk I have noticed this happen other years Jonny ......... sorry I can't be more help ... welcome to GOY .. you will enjoy it people are very friendly and helpful ... :o)