The Techny Arborvitae is a clone of its parent plant the White Cedar or American
Arborvitae. This special cultivar was found growing in Mission Gardens in
Techny, Illinois and due to its strong characteristics has been cloned ever
since and is sometimes called the Mission arborvitae. It is a medium growing
(1-2ft per year) evergreen that has a dark green soft foliage. In September of
each year it “sheds “ all the growth that grew out the previous year and it
drops to the ground creating a very nice mulch around the tree. Its parent plant
is a native to the northern US where it grows extensively and some fine, large
specimens can be found on Mackinac Island on Lake Heron in Michigan.
They can grow 30+ ft tall and 15+ft wide and the spreading root system is very
wind firm but the wood is not quite so strong and can be damaged by high winds,
snow and ice. This tree can live100 years or longer, its parent plant can live
over 500 years in the north. Age limiting factor is usually how close they are
planted together as close planting and dry weather will shorten life. This tree
has multiple leaders, so some damage to the top of the tree in ice and snow just
lets one of the other “leaders” take over so the effect is minor in a windbreak.
The foliage extends down to the ground, excellent for blocking winds. Deer will
eat this foliage in the winter and severe damage and death can result with
smaller plants, with larger plants all the foliage can be eaten off within 6 ft
of the ground. Deer reduction or fencing may have to be used in some areas.
The Techny Arborvitae grows well in a hardiness zone from 3-7 and likes over 25"
of rain per year in areas with adequate soil to hold moisture during the dry
months. Does not do well in sandy soil as has a shallow root system and in
droughty conditions, losses can result. Will grow well in high ph soils such as along gravel roads, in clay soils and soils with extra moisture. Should not be planted in states where hot dry summers usually occur (Nebraska, Montana, Wyoming, ect.) unless extra moisture can be provided.
Disease problem are few with no fungal disease problems and few insect problems
such as bag worms or spider mites in a dry hot summer. The Techny
Arborvitae has shown to be a better plant for use in windbreaks than any other
arborvitaes and is more drought resistant. We have tested then against the American, Nigra, Dark Green,
Emerald Green and Green Giant arborvitaes, and the Techny always comes out on
top. As with any arborvitae if you have less than 1 inch of rain in a 30
day period from May through September with hot conditions, you should consider
watering your trees no matter how big they are. A soaker hose, water tank,
or maybe letting the water dribble out of a hose can do the job and save your
A 2 ft potted tree should be over 8 ft tall in 5 years in good soil, adequate moisture, and total weed and grass control.
Many places on the internet say the Techny grows slow and does not get very big
(10ft)--this is untrue. Spacing--Is very important for this species, due to its shallow root system and most times are planted way to close
together. When planted too close and a major drought hits, the shallow root system cannot get enough moisture for this moisture loving plant and the weakest ones die or the bottom of the plants die back causing a decrease in windbreak efficiency. Single Row--
10-Ft apart, Double row-- 16 ft between rows and 12 ft apart between plants in row, Multiple rows--18 ft between rows and 14 ft between plants.
We highly recommend the Techny Arborvitae with certain restrictions: Proper
spacing and soil conditions should be followed. They are wind resistant and we set them 12 feet apart on the outside of our 3 or more rows of trees, and at least 16 feet from any larger evergreens.
Left Picture above:
Hedge-row of Techny Arborvitaes, 25 years old. Trimmed
back from the driveway, great one row windbreak.
Right picture above: eleven year old Techny and was started as a 2 1/2 ft potted
size and is now 16 ft tall, this tree has never been watered, fertilized or trimmed.
A field of our Technys in the spring, ready to be dug and put in the cooler, we
have thousands of these for sale.
Our potted trees
ready for sale.
Bagworm can be a problem with arborvitae, and other evergreens.
Here is a bagworm house hanging on a branch. The fat black
worm live in
the bag during the day and then in the evening they come out and chew
off the foliage. If you have arborvitae or any evergreens you
should walk threw your trees every year in mid June and July and check to see if you have any of these bags hanging
on your trees. If they can be caught early they are easily eliminated by
hand picking them off or spraying. To learn more about bagworms just do a
search on the internet as there is much information.
Update: In the winter of 08'-09' we got down to -38 degrees
here on the farm and most of Iowa received similar temperatures.
This extreme cold killed most of the bagworms in the state of
Iowa, we have a few reports of them still down near the Missouri border
and parts south and it looks like there back to there natural levels .
Keep a careful eye on your trees, and you should have no problems with
To the right is a row of arborvitae that has been hit by an infestation of
bagworms, this happened in just a couple of weeks. They have eaten all the
foliage off the trees and these trees are not going to survive. If they
were caught early when they first appeared they could have been easily
controlled and the trees would have survived with little damage. It
usually takes several years for the population to get this large to do this kind
of damage. Early detection is the secret to controlling bagworms, walk
threw your arborvitae and all evergreens during the summer, June and July,
looking for the bags as shown above. Take action if needed and one
insecticide I know works is called Onyx.