THANKS!
Kelly

White Cedar...as you call it "arborvitae"...is the one to please you.
Mind you, it has to be clipped....but planted at the 3, 4 or 5 foot height, then cut back about 6", will grow --once established, a foot a year.
12' you want.....12' you'll get in a short time--but be warned..12' is not where it'll stop...15', 20'...
but can be kept lower by annual clipping.

Proper name:
northern white-cedar --- Cupressaceae Thuja occidentalis L
Cultivars:
'Aurea' - A golden globe that needs little shearing.
'Boisbraind' - A plant 10 feet tall with dark green,
burn resistant foliage.
'Brabant' - This cultivar tends to form one central
leader thus minimizing stem damage from winter snows.
'Brandon' - A fast-growing, cone-shaped plant about 15
feet tall and 4 feet wide. Reported as suitable for
use on harsh sites.
'Chalet' - A narrow plant with a rounded top and lime-
green foliage. It will be 10 to 15 feet tall.
'Compact American' - A compact, pyramidal form reaching
a height of 25 feet and a spread of 8 feet.
'Danica' - A slow-growing, compact globe with dark
green foliage.
'Degroot's Spire' - A narrow, columnar form.
'Douglasii Pyramidalis' - A dense, columnar form with
twisted dark green foliage.
'Elegantissima' - A slow-growing, dense plant with
yellow branch tips.
'Filiformis' - A pendulous plant with long, thread-like
branchlets and bright green new growth.
'George Peabody' - A broad, upright plant with yellow
foliage. The foliage becomes more orange in winter.
'Gold Cargo' - A cultivar with gold foliage that is
reported to resist winterburn. The plant can be 25
feet tall and 6 feet wide.
'Golden' - A broad, upright form with bright yellow new
growth.
'Golden Globe' - A uniform oval with foliage a soft
yellow.
'Hetz Midget' - A slow-growing, compact plant.
'Hetz Wintergreen' - A narrow, upright form reaching a
height of 60 feet.
'Holmstrup' - Dark green foliage that holds its color
in winter. Broadly pyramidal.
'Little Gem' - A globe-shaped plant reaching a height
of about 3 feet.
'Little Giant' - A slow-growing, globe-shaped plant
with bright green foliage all year.
'Masonic' - Pyramidal form about 25 feet tall and 5
feet wide.
'Niagara Compact' - A globe-shaped plant more compact
than 'Woodwardii'.
'Nigra' - A symmetrical form with good dark green
foliage color.
'Pendula' - An open, weeping form with dark green
foliage.
'Pygmy Globe' - A dwarf, globe-shaped plant with bright
green foliage. Needs little shearing.
'Pyramidalis' - A narrow, columnar plant often used for
screens.
'Rheingold' - Yellow foliage that becomes orange yellow
in winter.
'Sherman' - A pyramidal form reaching a height of 30
feet and a spread of 12 feet.
'Sherwood Moss' - A dwarf plant 4 to 6 feet tall.
'Smaragd' ('Emerald') - Narrow habit with glossy green
summer color. Reported as resistant to spider mites.
Plants will be about 15 feet tall and 4 feet wide.
'Sudworthii' - Upright, broad plant with yellow
foliage.
'Sunkist' - A compact, broad plant with orange-yellow
foliage.
'Techny' ('Mission') - A fast-growing plant with dark
green foliage. Usually about 15 feet tall.
'Tiny Tim' - A compact, upright mounding plant.
'Umbraculifera' - A rounded, irregular plant, nearly 3
feet tall and 5 feet wide.
'Unicorn' - A narrowly compact plant with dark green
foliage.
'Wareana' - A slow-growing, broadly upright plant.
'Wintergreen' - A pyramidal form reaching a height of
30 feet that retains good green color in winter.
'Woodwardii' - A rounded form that retains its shape
without shearing.
'Yellow Ribbon' - A narrow, upright habit is combined
with yellow foliage all year.

Better to spend money on one or two larger trees, such as arborvitae (above), and intersperse with deciduous natives
like hornbeam, serviceberry or other smaller trees.
It depends on how much length you need to cover.
Personally, I dont care for any of the 'yellow' evergreens unless mixed with the deep green or blues. Alone, the yellows look like they are diseased.

The mix of evergreen (for shelter/nests) and hornbeam or serviceberry (for food) will attract song birds to your yard.
Pondy