Long hair has a long tradition among many Native American Nations. This song, Indian Drums, speaks to ways NA's have been forced to conform, including hair cutting.
Here is a story about the "6th sense" that long hair provides backed up by U.S. Military experiments.
Hair is an extension of the nervous system, it can be
correctly seen as exteriorized nerves, a type of highly evolved
‘feelers’ or ‘antennae’ that transmit vast amounts of important
information to the brain stem, the limbic system, and the neocortex.
Not only does hair in people, including facial hair in men, provide
an information highway reaching the brain, hair also emits energy, the
electromagnetic energy emitted by the brain into the outer environment.
This has been seen in Kirlian photography when a person is photographed
with long hair and then rephotographed after the hair is cut.
When hair is cut, receiving and sending transmissions to and from the
environment are greatly hampered. This results in numbing-out .
Significance of long hair here
http://www.whitewolfpack.com/2013/08/elders-talk-about-significance-of-long.html
Here is a story from among a nonNative community.
http://www.huffingtonpost.com/2012/01/30/jt-gaskins-cancer-survivo_n_1241873.html
A boy who is a cancer survivor is growing his hair to donate to Lock for Love. He was suspended for three days because it is against school policy.
Here is the story again
http://www.sott.net/article/234783-The-Truth-About-Hair-and-Why-Indians-Would-Keep-Their-Hair-Long
More about research from Vietnam
http://www.realfarmacy.com/the-truth-about-long-hair/
"Why is his hair so long?"
http://www.huffingtonpost.com/jennifer-canvasser/why-is-his-hair-so-long_b_5195341.html?ncid=fcbklnkushpmg00000063
Not about Native people, specifically, but very important thinking about hair.