In Vermont, white cedars have adapted to both swamps and dry cliffs
Where cedars grow determines how they reproduce
Northern white cedar is among the easiest evergreens to identify, with stringy bark and flat, scaly leaves. It’s commonly planted as ornamental. And, while it can be found in old fields, it won’t survive there in the long-term. It’s in swamps and on dry cliffs that cedar is most successful. In one environment cedar can reproduce through their roots and in the other, primarily through wind.
Cedar swamps and “layering”
The state’s northern white cedar swamps are found occasionally in the Champlain Valley and south into Rutland County, but they are more common in northeastern Vermont.
As the name suggests, these swamps are wet and may have deep peat or muck. These natural communities—or neighborhoods—might also include balsam firs and white pines; alder-leaved buckthorns and dwarf raspberries; and fine-leaved sedges, mosses, and liverworts. Due to the calcium-rich waters often found in these swamps, there also tend to be many rare plants species, including ram’s head lady’s slipper and small yellow lady’s slipper.
Swamps are one of white cedar’s favorite places.
In these swamps, cedars can reproduce from a branch in a process called layering. This means if you lay a branch down on moist ground and moss grows over it, each branch node can produce a new tree. Each new branch is called a “layer.”
Cedars don’t typically reproduce by layering. It only happens naturally in the swamps, where it doesn’t dry out. The layering technique is used often in horticulture; while moss helps hold moisture around the branch in the wild, horticulturists must keep the soil around the branch moist to encourage growth.
Cedar root showing layering. Photo by: Laura Kenefic, PhD, U.S. Forest Service
Dry cliffs and wind
Cedars can also be found in upland forests, which are drier. However, they don’t usually survive in uplands except on extremely dry cliff-tops. In these areas, the northern white cedars depend on wind pollination to create seeds. You can find the seeds in the brown, oblong cones. The seeds are also dispersed by wind, which typically happens in early fall.
With luck, a seed will land on a rotten log or stump, where it has a better chance of survival due to the warmth and moisture of these mossy seedbeds. Growth is slow; the average cedar will grow about three inches in its first several years.
Swamp cedars grow slowly but can live over 1,000 years
While northern white cedar grows relatively slowly in swamps and lowland sites, it can grow to be very old. Northern white cedars can easily reach 400 years old if undisturbed; a northern white cedar in Ontario dated more than 1650 years old.
Want to learn more about this fascinating tree?
Join Liz Thompson for a talk she gave on northern white cedars at one of our online events.