pepper tree

i have a pepper tree with the red berries....it is 25 years old and it has been fine....now it looks to be dying....new leaves forming on end of branches and these leaves look good but many branches are dying....
It has no apparent pests or leaf discoloration ..i have sprayed a solution to deter gophers and baited gophers when i can....it gets the same watering as usual...about twice a month...
there has been new closeby watering across the dry bed creek...
Is this tree water sensitive ? I don't know what to do to help it.
thank you for any clue. gerrie h

There are two types of Pepper trees common to So. Calif. California Pepper has leaves about 3/8th inch wide and the foliage is considered drooping. Brazillian Pepper are wider, perhaps 1/2" wide. They both have red berries. They are both very tough trees. They are also 'considerd drought tolerant' when established (not drought proof). However we have had way below normal rain fall in So. California the last two years so the gound is pretty dry in most areas unless they are in areas that get irrigion from other plantings close by. 'Watering every two weeks' does not say how much water or how it is applied. To do a proper job a sprinkler needs to be near the drip line of the tree (where the branches end). You can use a sprinkler on a hose and let it run for say, 30 minutes or so, you may need to move the sprinkler around the base of the tree to get all areas deeply watered. Also using a fertilizer around the drip line should also encourage new growth, use a dry fertilizer that you scatter on the soil, not a liquid fertilizer. I would suggest a deep soaking about every two weeks to encourage new growth. It is not practial to try to water a mature tree by hand, you will have to stand there too long to be effective.
Liquid fertilizers do not last but about 2 weeks, so most dry fertilizers are better for trees, they feed for a longer time.