Answer: 

 

One thing you didn’t mention—what types of shrubs are these?  Are they evergreens?  Did this shrub start to turn brown during the summer,

or did you notice it early this spring, once the snow melted? Do you have a pet, or does a neighbor’s pet (pet urine) have access to it? Does the rest of the shrub appear healthy?  Is it showing signs of new growth, such as new soft green shoots?  You will most likely

have to trim back the brown part, to allow new growth to start.   If a pet or some other kind of animal has access to it, there are sprays

this can be applied to repel/discourage it from coming around.  If this is a result of winter burn, the brown parts need to be cut back,

and the shrub should be wrapped in late fall, to protect it from winter burn this year.