oak tree - is it dying

[mwatsonxx]

Have two large oak trees in garden about 12 feet apart. I'd guess their age is + 50 years, trunks are appox 2 feet wide.
About 4 years ago one of them produced thousands of acorns I was removing 3 or 4 barrow loads a week. Since then I have noticed an increasing number of small (3" dia) dead branches and there are always lots of twigs under the tree.
Is it dying? and could it fall down without warning due to internal rot.
The tree looks perfectly healthy in spite of above.
Any advice much appreciated, thanks

[eeyore]

It is possible that the thousands of acorns was just a "mast year" a year in which seeding is unusually prolific - but it is also possible that it was brought on by stress. Our ops manager suggest that this could be caused by a fungal attack, but it is difficult to say from a descrription. If you are near MK I would be happy to come have a look, otherwise if you could post up some pictures of it including at least one showing the whole tree then I will see if we can give you a diagnosis

[mwatsonxx]

eeyore, I work in MK. I don't think a photo would be much good as tree is now full of leaves and anyway I can't get far away enough. What about if I cut a bit off and brought it to MK. Please advise what you would require for an analysis.