Original Mod Author's Description Below
This mod replaces the 2D snow berry plants of Skyrim with a 3D model. The
vanilla plant is clearly based off of Winterberry holly, Ilex, (and not
the real world snow berry plant) which I think was a good aesthetic
choice on part of Bethesda, so I therefore based these snowberry plants
off the same plants as Bethesda did. Each leaf of each plant model is
unique due to randomly assigned vertex colors and several leaf
variations within the diffuse. Vertex smoothing is done within the model
itself so that normal maps are not necessary. There are two model
variants (large bush and small bush) and four texture variants (Green,
Snowy Green, Variegated, and Snowy Variegated). In the default version,
the large bushes (commonly found in nature) are green and the smaller
bushes (commonly found in residential areas) are variegated. 

On Performance
I had originally planned on using the berries from Sufficiently Optimized Snow Berries (SOSB) by WankingSkeever, however, performance testing of various models of
berries revealed massive performance gains by reducing the number of UV
islands (from 32 UV islands in SOSB to 1 single UV island per berry in
this mod). Performance testing revealed that the best predictor of
performance was the data size of the nif or a crude summation of
triangle and vertex counts. Ultimately, I was able to make the berries
higher poly and also save considerable performance. These optimizations
will likely not be noticed however, because there are only ~2000 snow
berry plants across the entire map, so raising their geometric
complexity (within reason) essentially cannot affect performance (ie if
you drop a glass or barrel of water into the sea, which will raise the
sea level more?). Testing was done on a laptop, and FPS loss could not
be measured until vertex counts were well over several hundred thousand,
which is many many times greater than this mod (or any other snowberry
mod). For perspective, the small bush is 3178 triangles+2701 vertices
(about twice the data size as vanilla, and 1/5th the data size of SOSB)
and the large bush is 9752 triangles+8335 vertices (about 6x the data
size as vanilla, and 1/4th the data size of SOSB). As many of you know,
creating highly optimized and performance friendly mods is an obsession
of mine and fundamental to the Cathedral Series, and this mod offers the
best visuals to performance ratio possible.

Recommendations
Cathedral Snowberries - Inventory - Wreath - Hearthfires Planter by WankingSkeever
Cathedral Series

Credits
-Dr.Jacopo
-Please see the above Permissions & Credits drop down for texture source and licensing. 
-Massive thanks to WankingSkeever who helped me make this mod (even though it is in direct competition
with his) and even offered to let me use his berries. Please check out
his profile as he has many great mods!
-Sincere thanks to RallyEator who created the awesome snow masks for the snow models. Please check out his profile for his many awesome mods!
-Thank you Jampion for fixing the final bug with harvesting!