These distant mountains speak

[vagabond]

These distant mountains speak
in tones too low for the living to hear.              i think you could leave out this line as your poem is all about hearing those mountains - what is not possible is understanding what it is they could be saying, if anything.
Winter snow,
nestled on peaks
and crags,
is a single syllable --      i like this alliteration
a soft vowel sound.           "sound" might be unnecessary,  you could just write " a soft vowel".


I cannot hear the language   these 3 lines repeat parts of the first stanza.. could be omitted in my opinion.
of these mountains,
though I listen,


my bare feet                   maybe add a verb here, like for example how every step sounds different?
on stony soil,
my lips wet                          i´d like some description of the sound of these little (or bigger) streams 
with glacial waters.          


I sometimes hear the echo                       you could start this line with "sometimes those words echo in the ..."  ( i think the "I" is a bit distracting)
of those words
in the footfalls
of a cottontail rabbit,
in the hissing of a
rattlesnake hiding                  there are no toxic snakes where i live, i wonder would people walk around barefoot in rattlesnake territory?
in the tall, summer grass.                       


this seems like a meditation on the sound of a mountain, i like that idea.
i hope i didn´t make too much suggestions.. maybe some are useful