Hello Margaret, 

It appears as though these russian cypress have gotten a little too much direct light or may be in too hot of a location (or a combination of both!). It is a full sun plant, but considering our hot summer temperatures the spot that you have them may have been too much for them. If you have the same russian cypress growing in a more shady spot and those are doing better, I would consider moving these ones to a more sheltered location and replacing them with a more heat and sun tolerant plant. Have you noticed this type of browning in years past with any of these plants? It is possible that some of the browning could be attributed to "bronzing" which is normal for these plants in the fall and winter. It appears that this could be part of the case with the one in the second photo, maybe watch this one and see if with new growth and the change in seasons it starts to green up for you. 

I hope this helps. This article below also has a lot of great information about the russian cypress. 

Microbiota Decussata: Shrubby, Low-Growing Ground Cover - Epic Gardening

Thank you for reaching out to UVM Extension services and please let us know if you have any further questions.