Tree of the Week

Thuja occidentalis.

Some common names are Arborvitae, Eastern Arborvitae, Northern White Cedar.

The above picture is a Thuja I pruned over on Laguna Honda.

They come in many shades of green, yellow, or blue green with differing shapes and sizes. Sometimes the leaves can hang horizontal, vertical, or in waves. They are quite popular in San Francisco, especially in formal gardens. They are often hedged, sculpted, or sheared.

The name Arborvitae means tree of life. Rich in vitamin C, early European settlers and native Americans used it to fight scurvy.
Naturally occurring in Canada and the northern U.S., these shrubs are food for deer, hares, and porcupines. They are preferred building material for log cabins because they are good insulators and resist rot. They are also used as fence posts and siding for boats since they withstand water damage.
Since they naturally occur in both highlands and lowlands. You can find them growing out of rocky cliffs, on a mountain clearing, or in the ecotone (transition space) between a bog and a forest. They like calcium rich soil.
If you want them to thrive in your garden, plant Thuja where they can get full sun. Also keep the soil somewhat moist. Still, don’t over water. Just don’t let the soil get too dry for too long.
These are very hardy trees with few pests.
Thuja are very slow growing. They can get up to 50 feet tall given the right environment, but it may take 50 years. They can live for up to 1000 years.
Here is a photo of a famous, 300 year old Arborvitae in Minnesota, growing on the shore of lake superior. It is sacred to the Ojibwa Indian tribe who named it Manidoo-giizhikens, or Little Cedar Spirit Tree.

Here’s a link to where I got much of my information on the Arborvitae.