Hi Carolyn,

Sorry to hear about your trees!

A few things could be causing this.  The most common cause of the tips of needles browning in our area is winter injury--primarily desiccation from wind.  It could also be damage from salt--I notice that the trees in the photo are close to some concrete; if that is ever treated with de-icing salt, it could be contributing.  A soil test could tell you for sure if salt is an issue.

Lastly, waterlogged soil if the soil is compacted or receives too much water from runoff or irrigation could lead to the same symptoms.  Mitigation is possible for these if you determine that to be a problem.

More information and links can be found here:

https://planttalk.colostate.edu/topics/weeds-cultural-problems/2123-needle-browning-evergreens/

I hope this helps.

Cordially,

John