I did research and the shenmue tree is real.
It is a Peach tree it is similar to cherry blossom.
They even got a festival called Guilin peach blossom festival.
http://www.chinahighlights.com/festivals/gongcheng-peach-blossom-festival.htm
There is a river in Guilin called peach blossom.
http://www.guilinchina.net/guilin-city/peach_blossom_river.htm
The Shenmue Tree in the game.
[youtube]http://www.youtube.com/watch?v=IHa7kaDSW-Y[/youtube]
Here are pictures of peach blosoms on China and artwork
Peach Blossom and Mountains at Xiaopinluo Village China near Guilin during March
more pictures here.
http://www.chinaodysseytours.com/news/shanghai-peach-blossom-festival.html
He notice the tree looks similar to a cherry blossom.
In china they make many festivals about peach tree because of it blossom beauty the same way Japan makes festivals about cherry blossoms.
Remember Shenhua is from Miao Village They speak a different chinese dialet called Hmong that only their people speak and not everyone in china can understand because it is different than Mandarin the Chinese dialet most used.
Maybe in her dialet they call peach tree as shenmue.
Yu probably talking with someone there and they told him the name of the peach tree using their language and that name is Shenmue that or Yu make the name up(Which I doubt). But that Tree in the game is definitely a Peach tree.