Sunday, June 13, 2010

Thuja - Arborvitaes

A family of evergreen coniferous temperate to cold climate trees that are distant relatives of the Junipers.
Arborvitae is valued for landscaping and it timber; however a tea that is very rich in Vitamin C can also be made from its foliage.
The Arborvitaes prefer sun to partial shade and deep, fertile, well drained, cool soil on a site somewhat sheltered from wind. They grow best in humid climates unlike many of the Junipers. The Arborvitaes are also very flood tolerant and often grow on swampy sites. The best time to prune is in April and they should be pruned to a single leader to prevent splitting in heavy ice and snow storms.
Propagation can be from rooting half-hardened cuttings taken during late summer/early autumn then grown on in a cold frame or by seed sown during autumn. Soak seeds in water for 24 hours before sowing. Arborvitaes are also easily grown from cuttings of 6 to 9 inches long, taken during summer. Stick them in sand under mist ( or frequently hand mist them ). They will abundantly form roots in 6 to 12 weeks.

Thuja 'Green Giant' ( Green Giant Arborvitae )
A hybrid between Thuja plicata & T. standishii resembling the later in appearance, with rich glossy deep green foliage that retains that color over the winter. It is both extremely vigorous and deer resistant. It also typically grows with a single leader making it far less prone to splitting in ice storms and heavy snows than the Leyland Cypress. The Green Giant grows with hybrid vigor, reaching a growth rate up to 5 feet and can reach up to 27 x 8 feet in 6 years; 40 x 15 feet in 10 years and eventually 75 x 20 feet or more with age. It is typically broadly conical and dense, with a long leading shoot.
The Green Giant grows well on most soils and is hardy zones 5 to 8 tolerating as low as -25 F. It is deer, ice, drought, insect and disease resistant. Tolerant of heavy clay and hot humid summers. Propagation cuttings taken from July into March root easily under mist with bottom heat 3000 to 8000 ppm IBA.

* photo taken on May 1 2010 in Columbia, MD

* photos taken on Mar 14 2011 in Ellicott City, MD




* photos taken on Mar 23 2011 @ Brookside Gardens, Wheaton, MD


* photo taken on May 21 2011 in Howard County, MD

* blocking bad views and wind with the Green Giant - Mar 28 2011





* photo taken on Apr 3 2012 in Harford Co., MD

* photo of unknown internet source

* photos taken on Oct 23 2012 in Harford Co., MD

* photos taken on Sep 23 2013 in Columbia, MD


* photo taken on Oct 22 2015 in Columbia, MD

* photo taken on Mar 1 2016 in Columbia, MD

* photos taken on Oct 2 2016 in Harford Co., MD

* photo taken on Dec 20 2016 in Columbia, MD

* photos taken on Mar 9 2017 in Harford Co., MD

* photos taken on Mar 18 2017 @ Brookside Gardens, Wheaton, MD


* photos taken on Nov 9 2017 in Harford Co., MD


* photo taken on Mar 17 2018 in Harford Co., MD

* photos taken on Nov 10 2018 in Harford Co., MD



* photo taken on Nov 25 2019 in Columbia, MD

* photos taken on Mar 26 2020 in Columbia, MD






* photo taken on Sep 26 2020 in Howard Co., MD

* photo taken on Feb 18 2021 in Columbia, MD

* photos taken on May 23 2021 in Columbia, MD

* photos taken on Jan 7 2022 in Columbia, MD

* photo taken on Feb 11 2022 in Columbia, MD

* photos taken on Mar 8 2022 in Columbia, MD

* photos taken on Aug 11 2022 in Columbia, MD


Thula koraiensis ( Korean Arborvitae )
A very attractive, small, slow growing, broadly-conical tree, native to extreme northeast China and Korea, that can reach around 30 feet. Some records include: fastest recorded growth rate - 1 foot; 10 years - 10 x 6.5 feet; 20 years - 20 feet; largest on record - 65 x 15 feet with a trunk diameter of 1 foot.
The small scale like foliage is in large, broad flattened sprays that are mid-green above and silvery-white beneath. From a distance the foliage appears blue-green. The foliage is aromatic when crushed.
The oblong, yellow green cones ripen to brown and are up to 0.5 inches in length.
The red-brown bark peels in thin scales.
Hardy zones 4a to 8 and is tolerant of shade. Endangered in its native range and rare in cultivation. Deer resistant and very easy to grow. It should be much more widely used in landscaping.

* photo taken on June 23 2013 @ U.S. National Arboretum, DC

* photos taken on Apr 10 2018 in Columbia, MD



* photos taken on June 15 2018 in Columbia, MD


* photo taken on Mar 26 2021 @ U.S. National Arboretum, Wash, D.C.


'Glauca Prostrata'
A very attractive low growing shrub, reaching up to 2 x 6 feet.
The foliage is gray-blue above, silvery beneath.

* photos taken on May 27 2017 @ Meadowlark Botanical Gardens, Vienna, VA





Thuja occidentalis ( Eastern Arborvitae )
A very dense, conical, medium size tree to 60 feet that is native to North America ( from southeastern Manitoba to Lansdowne House, Ontario to the southern tip of James Bay to Gaspe & New Brunswick; south to Minnesota to northern Illinois to Ohio to Pennsylvania ). It is endangered in the wild in Illinois, Indiana, Ohio, West Virginia, Maryland, New Jersey, Connecticut and Massachussets. It was formerly more widespread in Ohio along the lakeshore and in the eastern part of the state. Some records include: fastest recorded growth rate - 3 feet with a trunk diameter increase of 1 inch; 20 years - 37 x 17 feet; largest on record - 150 x 50 feet with a trunk diameter of 7 feet. Some exceptionally large trees include: Leelenaw County, MI - 113 x 42 feet with a trunk diameter of 5.5 feet; Falls Conservation Area @ Benmiller, Goderich, Ontario - 60 feet with a trunk diameter of 6 feet.
Extremely long lived, trees up to 1890 years old grow on the Niagara Escarpment near Tobermory in Ontario, Canada. Exceptionally cold hardy, it does thrive in North Dakota if irrigated, however it does not grow quite as large with 45 x 30 feet being the largest known tree.
The Eastern Arborvitae and most of its cultivars tolerate clipping and can be used as a hedge or screen. Shearing is best done in spring and early fall.
The scale like, scented foliage is in flattened sprays is deep green above and paler green ( never white ) beneath.
The bark is orangish in color and peels in strips.
The wood is often used for fences.
The fruits is an upright, oblong scaly cone, up to 0.5 inches that is green ripening to brown.
Hardy zones 2 to 7, some of the hardier cultivars grow well in Alberta, Canada. Trial results were mixed at Indian Head, Sask. and Brandon, Manitoba where only seed grown from native populations in southeastern Manitoba and protected during the first few winters have done well. It is possible that some seed source from around Lansdowne House, ON area may even survive in zone 1. Tolerant of flooding but is very prone to roadsalt ( will brown the foliage ), deer damage and winter burn following dry falls. In severe climates, it is recommended to wrap them in burlap for the first winter to protect the foliage. Eastern Arborvitae does not enjoy pollution and extreme heat. An all purpose fertilizer application is recommended during early spring and mid autumn. The Arborvitae does thrive under Walnuts being that it is resistant to Juglone. Mulching to cool roots will enhance growth and care must be taken to deeply water foundation plantings if rainfall is blocked by the wall they are up against. Trees used for screening and windbreaks must have their root zone kept clear of weeds or turf or their growth will be greatly diminished. Propagation of the species is by seed however the cultivars can also be reproduced by softwood cuttings in summer.

* photos taken in Trucksville, PA on July 2006


* photo from family photo album taken @ Mackinac Island, Michigan 1974

* photos taken in Trucksville, PA on April 2010
























* photo taken on August 2 2010 in Bayfield, Ontario

* photo of unknown internet source

* photos taken on Nov 24 2012 near Wilkes-Barre, PA







* photos taken on Aug 4 2013 in Bayfield, Ontario












* photo taken on Oct 17 2013 in Olney, MD

* photos taken on Oct 31 2013 @ Hampton Ntl. Historic Site, Towson, MD







* photos taken on Apr 21 2014 in Trucksville, PA





* photos taken on July 27 2015 in Bayfield, ON











USDA-NRCS PLANTS Database / Herman, D.E., et al. 1996. North Dakota tree handbook

* photos taken on July 14 2016 in Tobermory, ON









* photos taken on July 16 2016 in Bayfield, ON






* photos taken on July 16 2018 @ Wye Marsh, Midland, ON




* photo taken on July 16 2018 in Midland, ON

* Thuja occidentalis in Otterville, ON

* Thuja occidentalis in Athens, ON

* Thuja occidentalis in Athens, ON

* photos taken on Aug 19 2021 in Elora, ON

* photos taken on Aug 22 2021 in Bayfield, ON

* photos taken on July 9 2022 in Bayfield, ON

* photo taken on July 8 2023 in Thornbury, ON

* historical archive photos








'Affinity'
A fast growing, narrow-pyramidal form, reaching up to 80 feet. It originated in Indiana as a joint product of the USDA and Indiana Department of Natural Resources and is valuable for use in windbreaks and screens.
The foliage is mid-green during summer, turning to yellow-green during winter.
Hardy zones 3 to 6.

* Photo courtesy of USDA NRCS.


'American Pillar'
A very fast growing, dense, narrowly-pyramidal to columnar cultivar that originated as a sport of 'Hetz Wintergreen. It originated with horticulturalist John E. Houser of Georgia. It reaches up to 4 feet in 2 years from a rooted cutting, 25 x 5 feet in 10 years, eventually reaching up to 50 x 7 feet. It is usually twice as dense branching than it's parent 'Hetz Wintergreen' and also tends to keep a better green coloring during the winter. It makes a great screen for a narrow lot.
The foliage is deep green.
Hardy zones 3 to 8

* photo taken on Oct 6 2021 in Howard County, MD


'Brandon'
An exceptionally hardy form used for screening, that can grow vigorously to 15 x 4 feet in 10 years, eventually to 30 feet. It is densely columnar in habit.
The luxuriant deep green foliage bronzes in the winter in colder regions.
Hardy north to zone 3a ( -40 F ), it is hardy on much of the Canadian Prairies though in Edmonton only thrives within the city. It is very important to make sure this tree is kept pruned to a single leader to prevent splitting during heavy snowfall.

* photo taken on June 19 2021 in Ellicott City, MD


'Brandon Gold'
Moderate growing, dense, narrowly-columnar in habit, reaching up to 15 x 6.5 feet.
The fine-textured foliage is bright golden-yellow at first, later turning to deep green.
Hardy zones 3 to 7

'Caespitosa'
Slow growing and rounded dwarf, reaching up to 16 x 20 inches in 10 years and a maximum size of 3.3 x 4 feet after many years. The very dense foliage is medium green.
Plants may be damaged by heavy snowfalls so it may be worth it to go outside with a broom or shovel to free your shrub.

'Danica'
Vigorous, very compact and globular in habit, reaching up to 3.3 x 3.3 feet in 10 years and eventually 4 x 10 feet after many years. The foliage is deep blue-green during summer, turning to bronze in the winter. It looks more like a dwarf Hinoki than a Thuja.
Plants may be damaged by heavy snowfalls so it may be worth it to go outside with a broom or shovel to free your shrub.

* photo taken on July 14 2016 in Tobermory, ON

* photo taken on Oct 6 2021 in Howard County, MD


'DeGroots Spire'
Upright and very narrow columnar in habit, reaching up to 16 x 4 ( rarely over 10 ) feet in 15 years and an eventual maximum size of 40 x 10 feet.
The twisted foliage is rich deep green in summer turning to bronze during winter.
This plant is an excellent way to achieve the look of a spiral Arborvitae without all the wasted time having to clip it.
Hardy zones 2 to 8. It is very important to make sure this tree is kept pruned to a single leader to prevent splitting during heavy snowfall.

* photo taken @ U.S. Botanical Garden, Wash., DC on Aug 25 2014

* photo taken on July 12 2019 @ Greenfield Village, Dearborn, MI

* photos taken on Jan 31 2021 in Columbia, MD

* photo taken on Sep 27 2021 in Laurel, MD

* photo taken on Oct 26 2021 in Columbia, MD

* photo taken on Apr 10 2021 in Columbia, MD

* photo taken on Jan 7 2022 in Columbia, MD

* photo taken on Apr 11 2022 in Columbia, MD

* photo taken on May 10 2022 in Columbia, MD

* photo taken on Oct 10 2020 in Columbia, MD


'Douglasii'
Also called 'Douglas Pyramidal'.
Moderate growing to vigorous and narrow-conical in habit, reaching up to 40 or more rarely 50 feet in height. The foliage is mid green, turning to bronze during winter.
It is very important to make sure this tree is kept pruned to a single leader to prevent splitting during heavy snowfall.

* photo taken on Jul 18 2017 @ Dominion Arboretum, Ottawa, ON


'Douglasii Aurea'
Narrow-columnar in habit, with spreading branches. It can reach up to 34 x 5 feet in 10 years, with an eventual maximum size of 45 feet.
The golden-yellow foliage turns to bronze during winter.
It is very important to make sure this tree is kept pruned to a single leader to prevent splitting during heavy snowfall.
'Elegantissima' is very similar, actually almost the same.

* photo taken on Jul 18 2017 @ Dominion Arboretum, Ottawa, ON

* photo taken on July 7 2023 @ Bayfield, ON


'Ellwangeriana Aurea'
Rounded when young, becoming pyramid shaped with age. It can reach up to 10 x 5 feet in 10 years and a maximum height of 33 feet after many decades.
Foliage is juvenile on young plants but later becomes adult. The golden yellow foliage becomes bronzish in the winter.

'Ericioides'
A spreading and rounded shrub with juvenile foliage that is dull green in summer and turning brownish in winter. It can reach up to 5 x 8 feet in 10 years and eventually 10 x 13 feet after many decades.
Plants may be damaged by heavy snowfalls so it may be worth it to go outside with a broom or shovel to free your shrub.

'Fastigiata'
Narrow conical in habit, reaching up to 40 x 6.6 feet in 20 years and 78 x 20 feet with great age. It is very important to prune to ensure this tree has a single leader since multi-trunked trees or trees placed next to walls will easily split or fall over after a heavy snowfall.
The foliage is similar to that of the species.

* Thuja occidentalis 'Fastigiata' in Alvinston, ON

* Thuja occidentalis 'Fastigiata' on Manitoulin Island, ON


* Thuja occidentalis 'Fastigiata' on Londesborough, ON


* Thuja occidentalis 'Fastigiata' in Galati, Romania

* photo taken on Sep 23 2022 in Columbia, MD

* photo taken on Apr 6 2023 in Columbia, MD


'Filiformis'
Moderate growing, up to 2 feet per year, reaching a maximum of 25 x 20 feet.
Branchlets are thin and weeping. The "whip cord" foliage is golden yellow to light green. Hardy zones 2 to 7

* photos taken on August 3 2010 @ University of Guelph Arboretum, Ontario


* photo taken on Feb 8 2015 @ U.S. National Arboretum, DC


* photo taken on Sep 3 2017 @ U.S. National Arboretum, D.C.


'Fire Chief'
Compact and upright-rounded in habit, reaching up to 2 x 2 feet in 10 years, eventually to 5 x 4 feet. It is more sturdy and resistant to splitting than similar 'Rheingold'
The foliage is bright golden-yellow during spring, turning to lime-green during summer. The foliage then turns to red during winter.
Hardy zones 3 to 7

* photo taken on Aug 9 2020 in Columbia, MD

* photo taken on Aug 2 2021 in Columbia, MD

* photo taken on Aug 27 2021 in Elkridge, MD

* photo taken on June 19 2023 @ Hershey Gardens, Hershey, PA


'Froebellii'
Rounded and very compact, reaching up to 3.3 feet in 10 years.

* photo taken on Aug 4 2021 @ U.S. National Arboretum, Washington, DC


'Gold Champion'
Upright, oval to rounded in habit, reaching up to 7 x 5 feet in 10 years, eventually 12 feet if not sheared.
The foliage is bright golden-yellow.
Hardy zones 3 to 7

* photos taken on May 10 2019 in Ellicott City, MD

* photo taken on May 16 2021 in Catonsville, MD


'Golden Emerald'
Also called 'Jantar'. Moderate growing and narrowly-columnar, reaching up to 4.5 x 2 feet in 6 years, eventually to 15 x 3 feet. It originated as a branch mutation of Thuja occidentalis ‘Smaragd’.
The new foliage bright golden-yellow, the older inner foliage becomes bright green.
Hardy zones 4 to 7

* photo taken on Sep 16 2022 in Ellicott City, MD

* photo taken on Mar 5 2024 in Elkridge, MD


'Golden Globe'
Rounded dwarf, reaching a maximum size of 6 x 7 feet with bright golden-yellow. foliage. Some records include: fastest recorded growth rate - 10 ( rarely over 4 ) inches; 10 years - 5 x 3 ( rarely over 3 x 3 ) feet.
Plants may be damaged by heavy snowfalls so it may be worth it to go outside with a broom or shovel to free your shrub.

* photo taken on August 3 2010 @ University of Guelph Arboretum, Ontario

* golden globe arborvitae @ Glencoe, ON

* photo taken on Sep 6 2019 in Laurel, MD

* photos taken on July 10 2023 @ Collingwood Arboretum, Collingwood, ON


'Gold Strike'
Moderate growing and narrowly-columnar in habit, reaching up to 15 x 4 feet. It originated as a branch mutation of Thuja occidentalis ‘Smargd'.
The foliage is golden-yellow at first, later turning to deep green.
Hardy zones 2 to 7

'Hetz Midget'
Very compact and rounded in habit, it reaches a maximum size of 5 x 8 feet after many many years. Some records include: 10 years - 2 x 2 feet.
The fine-textured foliage is deep green.
Plants may be damaged by heavy snowfalls so it may be worth it to go outside with a broom or shovel to free your shrub.


* photo taken on Aug 1 2011 in Luzerne Co, PA

* photo taken on Oct 6 2021 in Howard County, MD


'Holmstrup'
A dense, conical shrub that reaches up to 5 x 4 feet in 7 years, 6.6 x 4.5 feet in 10 years; 20 x 7 feet in 20 years and a maximum size of 30 x 10 feet after many decades. Foliage is rich medium green.
Tolerates poor drainage. Plants may be damaged by heavy snowfalls so it may be worth it to go outside with a broom or shovel to free your shrub.

* photo taken on Oct 15 2018 in Elkridge, MD


'Hot Head'
A moderate growing, dwarf, dense, rounded form, reaching up to 2.5 x 2 feet in 10 years, eventually to 4 x 4 feet.
The deep green foliage retains its color very well during winter.
Hardy zones 3 to 8, it is extremely tolerant of both heat and cold.

* photo taken on Aug 27 2021 in Elkridge, MD


'Janed Gold
Moderate growing and tightly-pyramidal in habit, reaching up to 8 x 4 feet in 10 years, eventually up to 20 feet. It is very similar to 'Smaragd' except for having golden-yellow foliage. It makes a great screen for narrow spaces.
The foliage is intense golden-yellow all year.
Hardy zones 5 to 8, the foliage is very scorch resistant as long as rainfall is adequate.

* photo taken on Aug 21 2017 in Elkridge, MD

* photo taken on July 27 2019 in Columbia, MD

* photo taken on Mar 17 2022 in Columbia, MD

* photo taken on Feb 2021

* patent photo


'Linesville'
Also called 'Mr Bowling Ball'. A very dense, compact, rounded, dwarf Arborvitae, reaching a maximum size of 4 x 6 feet, with very attractive, soft, juvenile, blue-green foliage that turns gray-purple during winter. Some records include: fastest growth rate - 6 inches; 5 years - 3 x 3 feet. It looks somewhat similar to a Globe Cryptomeria and is a great substitute for it in very cold climates. It is easily grown from cuttings.
Plants may be damaged by heavy snowfalls so it may be worth it to go outside with a broom or shovel to free your shrub.

* photo taken on June 25 2017 in Columbia, MD

* photo taken on July 15 2017 in Columbia, MD

* photo taken on Aug 1 2017 in Columbia, MD

* photo taken on Nov 3 2017 in Columbia, MD

* photo taken on Sep 26 2018 in Columbia, MD

* photos taken on Aug 9 2020 in Columbia, MD

* photo taken on Aug 4 2021 @ U.S. National Arboretum, Washington, DC

* photo taken on Aug 13 2021 in Elkridge, MD

* photos taken on Aug 2 2021 in Columbia, MD

* photo taken on Sep 4 2021 in Columbia, MD

* photos taken on Feb 17 2022 in Columbia, MD

* photo taken on July 3 2022 in Columbia, MD

* photos taken on Dec 21 2022 in Columbia, MD

* photos taken on Aug 6 2023 in Columbia, MD


'Little Gem'
Dense and rounded with deep green foliage. It can reach 2 x 2 feet in 10 years and a maximum eventual size of 6.6 x 8 feet.
Plants may be damaged by heavy snowfalls so it may be worth it to go outside with a broom or shovel to free your shrub.

'Little Giant'
A dense, globular dwarf form, reaching up to 2.5 x 3 feet in 10 years and an eventual maximum size of 6 x 10 feet though usually about half that.
The foliage is rich deep green.
It is exceptionally hardy, even thriving on much of the northern Great Plains including Alberta.

* photo taken on Aug 20 2011 @ Brookside Gardens, Wheaton, MD

* photo of unknown internet source

* photos taken on Sep 22 2020 in Columbia, MD

* photo taken on Aug 12 2021 in Columbia, MD

* photo taken on Mar 16 2022 in Columbia, MD

* photo taken on July 10 2023 @ Collingwood Arboretum, Collingwood, ON


'Lutea'
Dense and narrow, with golden foliage all year. It can reach up to 27 x 10 feet in 20 years and the largest tree known is 66 x 20 feet with a trunk diameter of 2 feet.
It is very important to make sure this tree is kept pruned to a single leader to prevent splitting during heavy snowfall.

* photo taken on July 25 2015 @ Niagara-on-the-Lake, Ontario


'Malonyana'
Fast growing, Very columnar in habit, preferrably with a single leader. Looks like an Italian Cypress. Some records include: fastest recorded growth rate - 1 foot; 10 years - 10 x 2 ( rarely over 8 ) feet; largest on record - 35 x 8 feet with a trunk diameter of 1 foot. Foliage is deep green all year long.
It is very important to make sure this tree is kept pruned to a single leader to prevent splitting during heavy snowfall.
Hardy zones 2 to 8

* photo taken on Aug 4 2021 @ U.S. National Arboretum, Washington, DC


'Malonyana Aurea'
Very similar to 'Malonyana' except with bright yellow foliage.

'Nigra'
Fast growing, dense and narrowly-conical, reaching up to 50 x 15 feet. Some records include: fastest growth rate - 3 feet x 0.7 inches; 20 years - 25 x 8 feet.
The foliage is very deep green all year, even in winter.
It is very important to make sure this tree is kept pruned to a single leader to prevent splitting during heavy snowfall.

* photo taken on Nov 28 2018 in Columbia, MD

* photo taken on July 8 2022 @ Woodlands Arboretum, Clinton, ON

* photos taken on May 19 2022 in Columbia, MD

* photo taken on Oct 14 2020 in Columbia, MD


'North Pole'
Moderate growing, narrow, upright and columnar in habit, reaching up to 5 x 1.2 feet in 3 years, eventually up to 15 x 5 feet. It originated as a selection of Wintergreen' made by Art Boe in Faribault, Minnesota.
The deep green foliage is highly resistant to wind burn.
Hardy zones 3 to 7

* photo taken on Oct 10 2020 in Howard Co., MD


'Ohlendorffii'
A globular dwarf shrub, reaching a maximum size of 5 x 3 feet in 10 years, that retains its juvenile foliage. Eventually it develops a broad-conical habit, reaching up to 12 x 8 feet in height.
The foliage is rich mid-green.

'Pendula'
Weeping in habit, it must be staked when young to encourage height growth.
Some records include: fastest growth rate - 1 foot; 10 years - 6 x 6 feet; 15 years - 10 feet; largest on record - 15 x 18 feet with a trunk diameter of 10 inches.
The foliage is luxuriant green all year.
It makes a most spectacular specimen plant once mature.

'Polar Gold'
An exceptionally hardy form used for screening, that can grow vigorously to 6.5 x 4 feet in 4 years, 15 x 5 feet in 10 years, eventually to 30 feet. It is fast growing, dense, narrow-columnar in habit. This form is similar to 'Brandon' except with golden-yellow foliage. It is faster growing and more cold and wind tolerant than 'Sunkist'.
Hardy north to zone 3a ( -40 F ), it is hardy on much of the Canadian Prairies though in Edmonton only thrives within the city. It is very important to make sure this tree is kept pruned to a single leader to prevent splitting during heavy snowfall.

* patent photos


'Pyramidalis'
A moderate to fast growing, dense, compact, columnar tree reaching up to 20 x 4 feet in 10 years, eventually up to 30 x 10 feet. It forms an excellent screen.
The soft-textured foliage is bright green.
It is very important to make sure this tree is kept pruned to a single leader to prevent splitting during heavy snowfall.

* photos taken on June 1 2014 @ Maryland Horticultural Society Garden Tour, Ellicott City



'Rheingold'
Dense and rounded with juvenile foliage that is pinkish when very young turning to golden-yellow then to golden-bronze during fall and winter. Some records include: fastest growth rate - 6 inches; 10 years - 4 x 4.3 feet; 15 years - 6 x 7 feet; 20 years - 10 x 8 feet; 50 years - 16 x 21 feet with a trunk diameter of 10.5 inches; largest on record - 30 x 25 feet. Very old plants develop a more upright habit.
Plants may be damaged by heavy snowfalls so it may be worth it to go outside with a broom or shovel to free your shrub.

* photo taken @ U.S. Botanical Garden, Wash., DC on Aug 25 2014

* photo taken on July 5 2016 in Columbia, MD

* photo taken on Dec 12 2016 in Columbia, MD

* photo taken on June 25 2017 in Columbia, MD

* photo taken on Oct 3 2017 in Columbia, MD

* photos taken on May 7 2019 in Columbia, MD




* photos taken on Aug 9 2020 in Columbia, MD


* photo taken on Aug 4 2021 @ U.S. National Arboretum, Washington, DC

* photos taken on Aug 20 2022 in Columbia, MD


'Sherwood Frost'
Fast growing, dense and upright conical in habit, reaching a maximum size of 12 x 7 feet. Some records include: 10 years - 6 x 4 feet.
The foliage is deep green and heavily speckled white. The foliage turns to bronze during autumn.
Plants may be damaged by heavy snowfalls so it may be worth it to go outside with a broom or shovel to free your shrub.

'Skybound'
An exceptionally hardy form used for screening, that can grow vigorously to 15 x 4 feet in 10 years, eventually to 30 feet. It is densely columnar in habit. It is nearly identical to 'Brandon' other than having deeper green foliage and superior hardiness.
The luxuriant deep green foliage bronzes in the winter in colder regions.
Hardy zones 2 to 7, it is hardy on much of the Canadian Prairies. It is very important to make sure this tree is kept pruned to a single leader to prevent splitting during heavy snowfall.

* photo taken on Apr 1 2020 in Columbia, MD

* photo taken on July 20 2021 in Columbia, MD


'Smaragd' ( Emerald Green Arborvitae )
A columnar tree often HORRIBLY misused. It should be trained to a single leader when young to avoid later splitting in heavy snows and it should not be placed too close to walls where it will grow towards the light and eventually fall over ( again after heavy snow ). It is often sold as spirals and buying one guarantees a lifetime of shearing as it can reach a growth rate of over 2 feet. Typically reaching 15 x 4 feet at maturity, some records include: 5 years - 7 feet; 10 years - 15 x 4 feet; 20 years - 27 x 4 feet; largest on record - 35 x 6.5 feet.
Foliage is verdant bright green and remains that color all winter as well.
Even if overused, it is still a very beautiful plant when used as a screen.

* photos taken on Aug 1 2012 in Windsor, Ontario


* photo taken on May 13 2015 in Pikesville, MD

* photo taken on July 27 2015 in Bayfield, ON

* photo taken on July 25 2015 @ Niagara-on-the-Lake, Ontario


* photo taken on July 14 2016 in Tobermory, ON

* photo taken on Mar 14 2017 in Pikesville, MD

* emerald green arborvitae in Detroit, MI



'Spiralis'
Moderately growing, narrow-columnar in habit with naturally spiraled branchlets bearing sprays of deep blue-green foliage. Some records include: 20 years - 23 x 3.3 feet; largest on record - 50 x 10 feet with a trunk diameter of 16 inches with great age.
It is very important to make sure this tree is kept pruned to a single leader to prevent splitting during heavy snowfall.

'Sunkist'
Fast growing, dense, compact and broadly-pyramidal in habit with golden-yellow foliage all year. The inner foliage becomes bright green. Some records include: fastest growth rate - 2 feet; 10 years - 10 x 5 feet; largest on record - 26 x 13 feet with a trunk diameter of 1 foot.
It is very important to make sure this tree is kept pruned to a single leader to prevent splitting during heavy snowfall.

* photo taken on August 3 2010 @ University of Guelph Arboretum, Ontario

* photos taken on July 5 2016 in Elkridge, MD


* photo taken on July 16 2018 in Midland, ON


'Techny'
Fast growing and broadly-pyramidal. Some records include: 10 years - 25 x 7 ( rarely over 15 ) feet; 35 years - 25 x 10 feet. Plants over 100 years of age may reach up to 70 x 15 feet. It makes an excellent tall hedge, screen or windbreak.
The foliage remains luxuriant very deep green, even in winter.
Hardy zones 2 to 8. Tolerates as low as -40 F, possibly lower on protected sites. The tough foliage is very resistant to wind burn. It is very important to make sure this tree is kept pruned to a single leader to prevent splitting during heavy snowfall.

* Techny Arborvitae on Manitoulin Island, ON

* Techny Arborvitae on Ottawa, ON

* photo taken on Sep 23 2022 in Columbia, MD

* photos taken on Nov 8 2022 in Columbia, MD

* photos taken on Apr 5 2023 in Columbia, MD


'Techny Gold'
Dense broad and pyramidal in shape reaching up to 15 x 10 feet in 8 years. It is the gold foliage form of 'Mission' and its hardy burn resistant vibrant gold foliage intensifies in color in the winter. Great as a specimum or screen. Hardy zones 3 to 8. Plants may be damaged by very heavy snowfalls so it may be worth it to go outside with a broom or shovel to free your shrub.

'Teddy'
A dwarf rounded form, with feathery juvenile foliage that is grayish-green.
Some records include: 10 years - 1.5 x 1 foot; largest on record - 4 x 4 feet.
It makes an excellent substitute for Boxwood hedging in harsh climates where the Boxwood will not grow. It also looks great in the rock garden.
Plants may be damaged by heavy snowfalls so it may be worth it to go outside with a broom or shovel to free your shrub.

'Wareana' ( "Siberian" Arborvitae )
Not really native to Siberia and probably named that because of its extreme cold tolerance, it makes a moderate growing, excellent upright, broad-conical large shrub or small tree. Some records include: 10 years - 10 x 12 feet; 20 years - 20 x 15 feet; largest on record - 26 x 17 feet with a trunk diameter of 2 feet.
It has dark green foliage is thicker and more leathery than regular Thuja occidentalis.
It is also more drought tolerant than regular Thuja occidentalis. Plants may be damaged by heavy snowfalls so it may be worth it to go outside with a broom or shovel to free your shrub.



* photo taken on May 25 2022 in Columbia, MD

* USDA-NRCS PLANTS Database / Herman, D.E., et al. 1996. North Dakota tree handbook.



'Wansdyke Silver'
A dense, pyramidal, dwarf form, reaching up to 4.5 feet in 10 years, eventually up to 7 x 5 feet.
The very attractive, deep green foliage is tipped and splashed creamy-white.
Hardy zones 3 to 7.

* photo taken on July 17 2010 @ Morris Arboretum, Philly, PA


'Wareana Lutescens'
Upright and conical in habit with foliage that is golden yellow foliage eventually aging to deep green. The tree will often appear yellowish-green from a distance.
Some records include: 10 years - 6 x 5 feet; largest on record - 35 x 18 feet with a trunk diameter of 2 feet. Golden yellow foliage

'Wintergreen'
Also called 'Hetz Wintergreen'. A fast growing, columnar tree reaching a maximum size of 50 x 10 feet. Some records include: fastest recorded growth rate - 3 feet; 8 years - 12 x 4 feet; 20 years - 30 x 9 feet.
The foliage luxuriant deep green the entire year.
It is very important to make sure this tree is kept pruned to a single leader to prevent splitting during heavy snowfall. It often naturally forms a strong central leader unlike many other cultivars.
'Wintergreen' is also more drought tolerant than most Thuja occidentalis cultivars.

* photo taken on Oct 10 2020 in Columbia, MD


'Woodwardii'
A moderate growing, dense, rounded shrub reaching up to 7 x 15 feet after many decades. Some records include: 10 years - 5 x 8 ( averaging 4 x 4 ) feet; largest on record - 10 x 20 feet.
The vertical foliage sprays are rich medium green, turning to bronze during winter.
Plants may be damaged by heavy snowfalls so it may be worth it to go outside with a broom or shovel to free your shrub.

* photo taken on Sep 23 2021 in Columbia, MD

* photo taken on Oct 5 2022 in Columbia, MD


'Yellow Ribbon'
Moderate growing, compact and upright narrow-pyramidal in habit. Some records include: fastest growth rate - 1.5 feet; 10 years - 11 feet; 20 years - 15 x 6 feet; largest on record - 30+ x 10 feet ( est. - likely 80+ year size ). This tree makes a beautiful screen.
The very attractive foliage is glowing bright yellow.
It is very important to make sure this tree is kept pruned to a single leader to prevent splitting during heavy snowfall.

* photo taken on Jul 18 2017 @ Dominion Arboretum, Ottawa, ON

* photo taken on Sep 3 2017 @ U.S. National Arboretum, D.C.

* photos taken on Sep 3 2019 in Columbia, MD







* photos taken on Jan 15 2020 in Columbia, MD




* photos taken on Mar 22 2021 in Columbia, MD

* photo taken on June 1 2022 in Columbia, MD

* photo taken on Sep 16 2022 in Ellicott City, MD

* photo taken on June 26 2023 in Columbia, MD


Thuja orientalis ( Oriental Arborvitae )
Also called Platycladus or Biota orientalis. A moderate growing, dense, rounded tree, that is native from northeast Iran to China and Korea. Some records include: growth rate - 2 feet; 20 years - 37 x 13 feet; largest on record - 120 x 80 feet with a trunk diameter of 12 feet; longest lived - 2000 years. It is rarely seen in the U.S. in it's species form.
The foliage, carried in flattened vertical sprays, remains lush mid-green all year. The foliage isn't very aromatic.
The bark is red-brown.
Hardy zones 5 to 9 ( seed source is important with some clones only hardy zone 6 and milder ) in full sun to partial shade on fertile, well drained soil. Drought tolerant but it does appreciate an occasional deep watering. It requires 15 + inches of average yearly precipitation. Though not thoroughly tested in the Great Plains, the Oriental Arborvitae has been recorded to grow 15 x 6.6 feet in 10 years in Iowa.
It is very heat tolerant, it is even vigorous in Florida.
The species should be trained to a single leader for a tree that does not split in heavy snowfalls.
Insect and disease problems are rare other than occasional bagworm or spider mites on very dry sites.



* photo taken on June 17 2010 in Silver Spring, MD

* photo taken on August 5 2010 in Clinton, Ontario

* photos taken on Aug 3 2011 in Columbia, MD


* photo taken by W.D. Brush @ USDA-NRCS PLANTS Database

* historical archive photo



* excellent photo link found on internet
http://www.fotomontaro.com/flora/cupressa/platycladus_orientalis.shtml

'Aurea Nana'
Slow growing, dense, upright-oval in habit, reaching up to 20 x 14 feet. Some records include: 10 years - 5 x 5 ( averaging 3 x 2 ) feet; 25 years - 10 feet; 60 years - 17 x 13 feet.
The foliage is beautiful golden-yellow during spring and summer, later turning to rich green during fall and winter.


* photo taken on August 3 2010 @ University of Guelph Arboretum, Ontario

* photo taken on May 7 2012 in Columbia, MD


* photo taken on Feb 8 2015 @ U.S. National Arboretum, DC

* photo taken on May 2 2015 in Columbia, MD

* photo taken on Apr 11 2015 in Columbia, MD

* photos taken on July 17 2015 in Columbia, MD


* photos taken on May 14 2016 in Columbia, MD


* photos taken on July 1 2016 in Columbia, MD


* photo taken on Mar 1 2017 in Columbia, MD

* photo taken on Apr 4 2017 in Columbia, MD


* Thuja orientalis 'Aurea Nana' in Lowbanks, ON

* Thuja orientalis 'Aurea Nana' in Thedford, ON

* Thuja orientalis 'Aurea Nana' in Detroit, MI

* photo taken on Mar 27 2019 in Columbia, MD

* photos taken on Feb 3 2020 in Columbia, MD


* photo taken on Aug 4 2021 @ U.S. National Arboretum, Washington, DC

* photo taken on Sep 29 2021 in Columbia, MD


'Bakeri'
Dense conical, reaching up to 8 feet in 10 years, with an eventual height of 20 feet.
The foliage is bright green.

* photo taken on Apr 4 2017 in Columbia, MD

* photo taken on Sep 23 2021 in Columbia, MD

* photo taken on Mar 7 2022 in Columbia, MD

* photo taken on Oct 5 2022 in Columbia, MD


'Beverleyensis'
Forms an upright cone, reaching up to 6 feet in 10 years, eventually to as much as 33 x 20 feet.
The attractive yellow foliage turns deep golden-yellow during winter.


* photos taken on Feb 8 2015 @ U.S. National Arboretum, DC



* photo taken on Apr 6 2017 in Columbia, MD

* photo taken on Aug 4 2021 @ U.S. National Arboretum, Washington, DC

* photo taken on Oct 22 2023 in Columbia, MD


'Blue Cone'
Same as species except with deep green foliage.

* historic archive photo


'Conspicua'
Columnar in habit with golden yellow foliage all year. It can reach 6.6 feet x 40 inches in 10 years and an eventual size of 17 feet.

'Elegantissima'
Narrow conical when young and widening with age, it can reach a height of 6.6 feet in 10 years and eventually 25 x 20 feet after many decades.
The foliage is yellowish-green, turning to bronze during winter.

* photo taken on July 25 2015 @ Niagara-on-the-Lake, Ontario

* photo taken on Mar 27 2023 in Columbia, MD


'Frankie Boy'
An upright, rounded, medium-sized shrub, reaching up to 5 x 3.5 feet in 10 years, eventually likely to around 9 x 8 feet.
The thread-like foliage is bright yellow-green, turning to oranish-bronze during winter.
Hardy zones 6 to 9 ( possibly 5b on a protected site ). It is recommended to wrap with rope or shear back 1/3 of new growth each year to encourage a plant that is sturdier to resist heavy snowfall damage.

* photos taken on Feb 8 2015 @ U.S. National Arboretum, DC


* photo taken on Sep 3 2017 @ U.S. National Arboretum, D.C.

* photo taken on Apr 24 2021 in Columbia, MD

* photos taken on Aug 4 2021 @ U.S. National Arboretum, Washington, DC


'Juniperoides'
A dense, rounded shrub with gray-gray to blue-green juvenile foliage that turns purplish in winter. It only reaches 2 x 2 inches in 10 years and an eventual size of 3.3 x 6.6 feet.

'Rosedalis'
Dwarf and rounded with soft juvenile foliage that is yellow in spring, green in summer then turning purplish plum by winter. It reaches up to 2 x 2 feet in 10 years and an eventual size of 5 x 4 feet.

* photo taken on Feb 8 2015 @ U.S. National Arboretum, DC

* historical archive photo

* photo taken on Aug 4 2021 @ U.S. National Arboretum, Washington, DC


'Semperaurea'
Vigorous and upright, oval in habit, reaching around 10 x 10 feet in size, though sometimes much larger. The largest on record is 30 x 38 feet with a trunk diameter of 22 inches.
The foliage is golden yellow in vertical sprays.

* photo of unknown internet source

* photos taken on June 1 2014 in Ellicott City, MD



* photos taken on Feb 8 2015 @ U.S. National Arboretum, DC


* semperaurea oriental arborvitae in Indiana


'Sunshine Point'
Fast growing and very pyramidal in shape. It was selected especially for thriving in arid western Oklahoma by Sunshine Nursery of Clinton, OK.
The new growth is golden-yellow.

'Van Hoey Smith'
Upright in habit, reaching up to 8 x 3 feet in 10 years, eventually 15 feet or more.
The foliage is heavily variegated bright golden-yellow.
Hardy zones 6+

* photos taken on Aug 4 2021 @ U.S. National Arboretum, Washington, DC



Thuja plicata ( Western Red Cedar )
A very tall, handsome, dense columnar tree reaching up to 200 feet, that is native to western North America ( from Wrangell, Alaska to Kitsault, British Columbia to the Alberta Rockies; south to northern California & Idaho ). Some records include: 20 years - 66 x 24 feet; 30 years - 82 feet; largest on record - 277 x 70 feet with a trunk diameter of 29 ( 22.5 as the modern record ) feet. Longest lived - life expectancy up to 3000 years is possible and one northeast of Elk River Idaho with a trunk diameter of 18 feet is estimated to be exactly that. One tree of approx. 180 x 54 feet with a diameter of 20 feet grows in Olympic NP, Washington State. Despite being native to the Pacific Northwest, it also grows well in the east and has even reached a growth rate of 4 feet on hard clay in North Carolina. It also grows large in the east with 87 x 25 feet with a trunk diameter of 3 feet being recorded at Penn State Univ., Mont Alto, PA. One tree grew 18 feet in 14 years on pure sand at Cape Cod, Massachussets.
The aromatic, foliage appears of flattened, horizontal sprays and is very dark, glossy green above and varying from grayish white to bright green below.
The fruit is an oval, upright cone up to 0.5 inches in length. They are yellow-green ripening to brown.
The reddish-orange bark peels vertically.
The rot resistant wood is used for boats, siding, shingles and fenceposts. The tough, light wood splits easily.
Seed stock from the mountains of Montana generally grows the best in the northeast U.S.
Hardy zones 4 to 8 ( as much as zone 3 for seed source originating in the northern Rockies ). Prefers soil PH from 5 to 7 and is flood tolerant.

* photos of unknown internet source


* photos taken on Aug 25 2011 @ Scott Arboretum, Swarthmore College, PA


* photos taken on May 7 2014 @ London Town Gardens, Edgewater, MD



* photo taken @ U.S. Botanical Garden, Wash., DC on Aug 25 2014

* historical archive photos































* photos taken on July 14 2016 in Tobermory, ON


* video found on Youtube









* photo taken by K.D. Swan @ USDA-NRCS PLANTS Database


'Atrovirens'
Also called ' Virescens'. Very fast growing and upright-conical with graceful drooping branches. It will reach up to 60 x 18 feet in 25 years and an eventual maximum size of 100 x 25 feet.
The foliage is very glossy, bright green, later turning to rich deep green. The foliage may turn bronze during very cold winters.
It is deer tolerant making an excellent screen in areas that T. occidentalis would be devoured.

* photo taken on Aug 25 2011 @ Scott Arboretum, Swarthmore College, PA


'Aurea'
Narrow conical habit, reaching a maximum size of 50 x 15 feet.
The new shoots are gold tipped and later fading to yellowish green. The foliage often turns bright orange-bronze during winter.

'Can Can'
Extremely dense, broadly-conical and semi-dwarf in habit, it can reach up to 8 x 6.5 feet in 10 years, with an eventual size of 15 x 6 feet. It is great where a not so large screen is desired.
The very deep green foliage is tipped creamy-white.

'Cuprea'
A broadly-pyramidal shrub, reaching up to 3.3 x 3.3 feet in 10 years and eventually 5 x 7 ( rarely over 4 ) feet.
The deep green ( with yellow tips ) foliage turns to bronze during winter.

* photo taken on Feb 8 2015 @ U.S. National Arboretum, DC


'Ember Waves'
Moderate growing and pyramidal in habit, reaching up to 25 x 8 feet. It is an offspring of Thuja x 'Green Giant'.
The foliage is intense golden-yellow at first, eventually turning to lime-green. The tips of the foliage often turns to intense glowing orange-red during autumn.
Hardy zones 5 to 8.

* photos taken on Mar 15 2019 in Elkridge, MD


* photo taken on July 20 2021 in Columbia, MD

* photo taken on Feb 2020 in Columbia, MD


'Emerald Teardrop'
Moderate growing, compact, dense, upright and pyramidal in habit, reaching up to 6 x 2 feet in 4 years, eventually to 15 x 8 feet. It makes a great hedge or screen.
The healthy deep green foliage keeps its color well during the winter.
Hardy zones 5 to 8, it has excellent heat tolerance, tolerating as least as high as 113 F. It also has good wind tolerance.

'Excelsa'
Vigorous, dense, narrow, strongly-columnar in habit, reaching up to 13 x 10 feet in 10 years, eventually to 50 x 17 feet in size.
The foliage is glossy deep green even in winter.

* video found on Youtube


'Goldy'
A moderate growing, compact, pyramidal small tree, reaching up to 3.8 x 2 feet in 5 years, 6 x 4 feet in 10 years, eventually to 20 x 5 feet. Some records include: fastest growth rate - 1 foot.
The foliage is intense golden-yellow at first, turning to lime-green.
Hardy zones 4 to 8

* photo taken on Apr 6 2017 in Elkridge, MD

* photo taken on Sep 20 2023 in Howard Co., MD


'Green Sport'
Foliage does not brown in the winter, even in the midwest.

'Grune Kugel'
Slow growing, dense and rounded, reaching up to 2 x 2.5 feet in 10 years, eventually to 3 x 4 feet. It seems to be sturdier than many globe forms of Thuja occidentalis during heavy snowfalls.
The thick, coarse foliage is luxuriant bright green, turning to purplish-bronze during winter.
Hardy zones 5 to 8

* photo taken on June 19 2021 in Columbia, MD


'Hillieri'
A very dense, dwarf rounded shrub, reaching up to 20 x 12 feet in 40 years, and an eventual maximum size of 25 x 15 ( usually less than half ) feet.
The thick foliage is deep blue-green, turning bronze during winter.

'Hogan'
Also called 'Fastigiata'. Fast growing and broad-columnar in habit, reaching a maximum size of 150 feet. Some records include: fastest recorded growth rate - 4 feet; 4 years - 13 feet.
The foliage is verdant rich-green.

'Hoyt'
Generally similar to species, it is fast growing and columnar.
Very drought tolerant and disease resistant.

'Rogersii'
A very dense, upright, broad-conical, dwarf shrub with deep green foliage that is tipped golden bronze. It can reach 32 x 20 inches in 10 years, 6 feet in 20 years and eventually 7 x 8 feet.

'Semperaurescens'
Reaches up to 73 x 20 feet after many decades with yellowish-green foliage

'Spring Grove'
Also called 'Green Sport'. A fast growing, narrow-conical, large tree with foliage that is glossy deep green all year. It can reach up to 20 x 8 feet in 10 years, reaching an eventual average size of 70 x 20 feet.
Hardy zones 4b to 7 ( tolerating -25 F with no damage ). Both deer and bagworm resistant.

'Stoneham Gold'
A slow growing, broad-columnar, semi-dwarf with foliage that is bright orange-yellow at first, later turning to very deep green. Some records include: fastest growth rate - 2 feet ( usually much slower ); 15 years - 6 x 2 feet; 50 years - 16 x 10 feet; largest on record - 25 x 15 feet. It originated as a seedling of 'Aurea'.
Hardy zones 5 to 7

'Sugar and Spice'
A moderate growing, narrow, upright form, reaching up to 6 X 2 feet in 6 years, 12 x 4 feet in 10 years, eventually to 2o x 7 feet or slightly more.
The intensely bright green foliage typically retains its color well during the winter.
Hardy zones 5 to 8

* photos taken on June 17 2021 in Elkridge, MD


'Sunshine'
Fast growing, and upright, broad-conical in habit with horizontal branching.
It can reach up to 20 x 6 feet in 10 years, with an eventual size of 70 x 25 feet.
The foliage is bright yellow at first, later turning to yellow-green.
The foliage keeps its color very well in hot sun.
The pendulous foliage tips turn bronze during winter.
Very spectacular when used as a screen, it is a great replacement for Leyland Cypress.
Hardy zones 4 to 8

* photos taken on July 27 2019 in Columbia, MD




'Whipcord'
A slow growing, dwarf, compact form, reaching up to 6 x 3 feet in 10 years, with an eventual maximum size of 8 x 5 feet.
The glossy mid-green, long, weeping, whipcord foliage turns to bronze during winter.
Hardy zones 4b to 8.

* photo taken on July 11 2014 @ Smithsonian Inst., Wash., DC


'Zebrina'
A fast growing, dense, broad-conical, very large tree, with very attractive, feathery, deep green foliage that is heavily banded yellow giving it a variegated appearance.
Some records include: fastest recorded growth rate - 4 ( rarely over 2 ) feet; 10 years - 17 x 6 feet; 45 years - 70 x 50 feet; 100 years - 130 feet in height with a trunk diameter over 5 feet in 100 years in England; record size - 200 feet after a few hundred years ( estimated ).
Hardy zones 5 to 7 ( also 8 in west ). It is very heat tolerant.

* photo taken on July 26 2015 @ Niagara Parks Bot. Gardens, Niagara Falls, ON


'Zebrina Extra Gold'
Similar to 'Zebrina' but slower growing, only reaching about 30 x 10 feet in 20 years and 40 x 13 feet in 45 years. The foliage is also even more heavily banded yellow.

Thuja standishii ( Japanese Arborvitae )
A large, very beautiful, irregular, broad conical, large tree, reaching around 70 feet, that is native to mountain forests of central Japan at elevations around 5000 feet. Some records include: growth rate - 2 feet, 20 years - 40 x 16 x 1.7 feet; largest on record - 120 x 60 feet with a trunk diameter of 13 feet. Very long-lived, the Japanese Arborvitae can live up to 600 years. This elegant tree is very rare in the wild.
The foliage is flattened and deep green above and whitish beneath. Unlike Thuja occidentalis; the Japanese Arborvites foliage remains luxuriant green all winter long.
The rich red bark peels in plates and strips.
Hardy zones 5 to 8, it is quite likely hardy to zone 4b as it has grown well at Dominion Arboretum in Ottawa, Canada. An important timber tree in Japan.

* photos taken on August 3 2010 @ University of Guelph Arboretum, Ontario



* historic archive photos



Thuja 'Steeplechase'

* photos taken @ Howard Comm College on Aug 3 2023 in Columbia, MD

* photo taken on Aug 4 2021 @ U.S. National Arboretum, Washington, DC

* photo taken on Aug 7 2023 @ Howard Comm College, Columbia, MD


Thuja sutchuensis ( Sichuan Arborvitae )
A CRITICALLY ENDANGERED tree native to eastern Sichuan province China that can reach up to 66 x 30 feet with a trunk diameter of 4.5 feet and can live up to 600 years. It was considered to be extinct for over 100 years until rediscovered in 1999. This very attractive conifer is broadly-pyramidal in habit.
The flat sprays of foliage are glossy bright green above, whitish beneath. The attactive fibrous bark is cinnamon-red.
Hardy zones 6 to 8. Rediscovered in 1999 after being presumed extinct for 100 years. Not known in cultivation.

Thuja 'Titan'
A hybrid between Thuja standishii and T. plicata just like 'Green Giant' but is more upright and deeper green. It is rapid growing, reaching up to 23 x 10 feet in 10 years, eventually up to 45 x 12 feet.
The deep green foliage retains its color well during winter.
Hardy zones 5 to 8, it has excellent salt spray and urban tolerance.

Thujopsis dolobrata ( Hiba Arborvitae )
A moderately fast growing, broad-columnar to conical, large tree, reaching around 100 feet, that is native to Japan and neighboring parts of Korea. Some records include: growth rate - 2 feet ( average ); 5 years - 8 feet; 20 years - 40 x 13 ( averaging 25 x 11 ) feet; largest on record - 200 x 33 feet with a trunk diameter of 6.5 ft. Very long-lived, it can persist as long as 1000 years.
The scale-like leaves, up to 0.25 inches in length, are borne on flattened sprays. The beauriful foliage is glossy very deep green above, silvery beneath.
The foliage remains luxuriant green througout the year.
The fruit is a rounded cone, up to 0.5 inches long, that is green ripening to brown.
The red-brown bark peels in thin vertical strips.
Hardy zones 4 to 8 ( seed source from southern Japan may be less hardy ) in full sun to partial shade on acidic well drained soil; it loves hot humid summers but is not drought tolerant.
Generally very well adapted to the Mid Atlantic and northeast U.S. While preferring a site sheltered from winds, the Hiba Arborvitae can tolerate as low as -32 F. It is usually grown from seed as cuttings do not root easily.

* photos taken Feb 2009 @ U.S. National Arboretum, D.C.


* photo taken on March 28 2010 @ U.S. National Arboretum, D.C.


* photo taken on April 11 2010 @ U.S. National Arboretum

* photos taken on 4th of July @ U.S. National Arboretum, D.C.


* photo taken on July 17 2010 @ Morris Arboretum, Philly, PA

* photo taken on August 3 2010 @ University of Guelph Arboretum, Ontario

* photo taken on June 23 2013 @ U.S. National Arboretum, DC

* photos taken on Oct 21 2014 @ Smithsonian Inst., Washington, DC


* historical archive photos





* photo taken on Apr 24 2016 @ U.S. National Arboretum, DC

* photo taken on Apr 23 2017 @ Brookside Gardens, Wheaton, MD

* photo taken on Sep 3 2017 @ U.S. National Arboretum, D.C.

* photo taken on Aug 4 2021 @ U.S. National Arboretum, Washington, DC


'Aurea' ( Golden Elk Horn Arborvitae )
Upright, conical and semi-dwarf, reaching up to 6 x 4 feet in 10 years, eventually around 20 feet.
The flat sprays of foliage are golden-yellow.

'Hondai'
Clone from northern Japan that are fully hardy in zone 4.

* historic archive photos


* photo taken on Aug 4 2021 @ U.S. National Arboretum, Washington, DC


'Koreanum'
Clones from Korea that are fully hardy in zone 4.

'Nana'
Flat and spreading to 2 x 5 feet in 10 years, eventually to 8 x 6 feet.


* photo taken on annual Horticultural Society of Maryland Garden Tour

* photos taken on 4th of July @ U.S. National Arboretum, D.C.




* photo taken on June 23 2013 @ U.S. National Arboretum, DC

* photo taken on Feb 8 2014 @ U.S. National Arboretum, DC

* photos taken on Mar 26 2021 @ U.S. National Arboretum, Wash, D.C.


'Tom's Best'
* photo taken on Aug 4 2021 @ U.S. National Arboretum, Washington, DC


'Variegata'
Foliage is bright, shiny green with irregular cream splashing above, and marked silvery white below. Otherwise this tree is very similar to regular Thujopsis dolobrata.

* photo taken on Feb 8 2015 @ U.S. National Arboretum, DC

* photos taken on Mar 18 2017 @ Brookside Gardens, Wheaton, MD


* photo taken on Apr 23 2017 @ Brookside Gardens, Wheaton, MD

* photo taken on Sep 3 2017 @ U.S. National Arboretum, D.C.

* photo taken on Aug 4 2021 @ U.S. National Arboretum, Washington, DC


ADDITIONAL ARBORVITAES ( Text descriptions coming soon )
https://www.freepatentsonline.com/PP32048.html
https://www.freepatentsonline.com/PP31298.html
https://www.freepatentsonline.com/PP25363.html
https://www.freepatentsonline.com/PP16094.html

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