Question
the 60 yr old redwood in my yard has about 1*/8th of the needles turned yellow,
which I have never seen over the past 19 yrs.  is it sick?  thanks!

Answer
Roger:
This symptom may indicate a potential root/soil related stress. This may be water or nutrient related. Be sure it is getting enough water, especially if it has been hot/dry or excessive wind in your area over the past few months.  Look the base or trunk of the tree over for any type of loose or damaged bark or even digging under the tree.  If everything seems fine, you may consider the water or fertilizer possibility.

Regards
Steve