We moved into our home 41 years ago and enjoyed but never did much to sustain a wonderful green arborvitae hedge going the length of our driveway against the backyard of our next door neighbor’s yard.
For the first 5 years or so we did not do much to it, but we heard from the next door neighbor how the Blizzard of 78 had smashed it about and required some lifting and wiring. When new neighbors moved in they suggested we go in together on a landscape crew to keep it in check annually on both sides. We did that with them for the next 20 or so years. The crew would use gas hedge trimmers on the sides and sometimes trim the tops. Like this:
So for these 24 years we kept it pruned and under control. Then new neighbors arrived; the landscapers familiar with this arborvitae retired. The distractions of 4 children growing up played their role and we just let the pruning lapse…. for more than 10 years. This resulted in an over-tall, over-wide and overgrown arborvitae. We saw this most as the cars hit branches driving down the driveway. It evolved from this full width view in September, 1979:
Here we see views from 1981 and 2020 that show the widening girth:
This video shows the original edge of the arborvitae, marked by a gate post from 1986, and its width today – 3 to 4 feet into the driveway.
And these Satellite views from Google Earth demonstrate the change effect: (interactive: slide the bar.)
It turns out that this arborvitae, literally from the Latin “Tree of Life”, is a Thuja plicata. ‘Thuja’ comes from Medieval Latin thuia, ultimately from Greek thua, the name of an African tree; ‘plicata’ comes from the Latin word plicāre and means “folded in plaits” or “braided,” a reference to the pattern of its small leaves. According to Wikipedia it is also called a giant arborvitae and “is a particular species of Thuja, an evergreen coniferous tree in the cypress family Cupressaceae native to western North America. ” These trees are amazing in that, left on their own can range up over 200 feet tall and over 20 feet in trunk diameter. According to Cooperative Extension — University staff from Land-Grant institutions from across the United State — the hedge version can grow up to 60 feet tall, depending on the cultivar. It is long-lived; some individuals can live well over a thousand years! Here’s one left to its own devices in British Columbia,
One would think that to fix the overgrowth we could simply cut it back, way back, and let it restart from the stumps. But Arbor Vitae are not like other hedges. Only the last foot or so of each lateral branch offers green growth and if you cut it back to beyond that green growth part it will not grow back at all. It will look like these:
According to Larry Hodgson, one of Canada’s best-known garden communicators, “If your cedar hedge has become far too wide or far too tall (and that happens quickly if you fail to trim it annually, remembering that cedars will grow from 1 to 3 feet/30-90 cm a year!), pruning it back to a more acceptable size will probably not be possible. Unlike a non-conifer hedge that you can cut back almost to the ground if necessary and that will then grow back fairly, if you prune into the old wood of a cedar hedge, any regrowth will be irregular, leaving it with a[n] open top and sides full of dead patches that will take years to recuperate, if indeed they ever do. You’ll find it is better tear the hedge out and start all over.” Hard words from Larry!
This clip shows the growth in girth and height over the last 20 years (roughly doubling in width and height) along with a depiction of the interior of the hedge, which is branches devoid of green growth.
We loved the hedge, its privacy, the way the birds flocked to it and could not, despite Larry’s advice, cut it down to “start anew”. We needed to find a way to somehow regenerate inner growth and allow thinning of the outer edges. We searched for someone to show us how or do it.
To the rescue came Wes Ford, a local arborist. He said he could prune it and proceeded to, essentially, give it a crew cut at about the 15 foot mark. Topping the peaks of the hedge. He claimed that this sunny opening into the dead wood middle of the over-wide hedge would result in new growth in the middle of the hedge that will make it into a veritable “green block”.
Would that it were so. Two years later the hedge had not returned to life in the center. The inner section remained “dead and bare” as depicted here:
It turned out that squirrels added to the problem. They tore strips of bark off the trunks with their mouths to use for their nests. This left the trees unable to grow.
This panel discussion in Houzz has arborvitae maintainers from Michigan, Wisconsin, Washington and Oregon all complaining about the same thing. One sent in a picture of his destroying squirrel.
Our current hope is that applying this red fox urine to the bases of every tree stalk will keep them at bay.
A few years after Wes we asked Bogan Tree for an opinion and John ____ an arborist from Bogan, confidently explained that the center would grow if we pruned away enough of the tops and sides to let light into the center. When I told him that Wes Ford had expected a “Green Block”, John concurred saying his only question was why it had not! He had worked on the trees at Harvard University and said that he would try assiduously to get the ground crew to avoid just surface cut trimming the outside of bushes and instead occasionally trim out larger branches to allow shafts of light into the center getting them to regenerate the centers and avoid this hollow heart syndrome.
I asked him for a quote on the pruning. He explained that the pruning would involve long duration, arduous and continually repeated work that would cost prohibitive amounts if done by a tree firm. This cost would become especially high if they needed to do it with a “Cherry Picker” / “Bucket Truck” which, he said, they would need in our case.
So we decided to try and do it ourselves ! We would move forward, following the guidance of John and the words of Larry Hodgson, “… you can’t realistically make a fat hedge much thinner, you can shorten a tall hedge considerably, as long as you don’t expect perfect results in the near future. To try this, prune the hedge at least a foot (30 cm) lower than you really want it to be. At first this will leave a hedge with green sides and a dead top. However if you prune carefully every year, allowing the hedge to grow about 2 inches (5 cm) taller each season, you will gradually be able to encourage the side branches to grow inward and start to fill in the dead center. The gaping hole at the top will then eventually fill in, leaving you with an acceptable hedge. Remember though that this can take years.” So years it will take!
John went further and explained how we should do it and what tools we’d need. Beyond the standard lopper and clipper (left) …
…we’d need a pole pruner / lopperpruning ladder. We purchased the Jameson Big Mouth Pruner/Saw Package with pole extension, and a saw. He explained where to get high quality versions of these products at very fair prices, Forestry Suppliers.
We quickly ordered the Jameson pieces and spent some time to hone in on the Hasegawa Tripod Ansi Orchard Ladder – 3 legs, wide base, no wobble and remarkably light! from Shelter Tree in North Attleboro MA. The combination of the two gave us what we needed:
We found out that squirrels caused part of the problem of “no inner growth”. The had been stripping the bark off trunks to then make their nests in the trees! Very upsetting.
But we got into the pruning earnestly only this year. At the beginning we focused on trimming W driveway side as far back as we could and topping the sides. Experts advise that before you can widen the car height path, you need to trim back the top. From Larry again, “..For a hedge to remain green from the bottom up, it has to be broader at base than at the top. That way, its bottom leaves won’t be shaded by the growth above and will therefore receive their share of sunlight rather than thinning out over time and losing their foliage. Also the top should be rounded or pyramidal so it will shed snow and ice more readily and therefore not split open on those tough winter days.”
We were in the poor shape group.. the bottom left of the chart. So…. we needed to start at the top and trim in more there than at foot level.
So it involved a long process of top down trimming starting at the street end and continuing down this whole length of arborvitae:
But when we finished trimming the sides it did not look finished. First we could not trim back from the driveway that far because there was no green growth in the interior and second the top center and neighbor’s side were thick with over grown peaks. We’d need to find a way to get up into the top center and trim both there and over to the neighbor’s top sides.
And we came up with a way of weaving in a regular ladder through the side openings, setting it up in the center and from there reaching out with the pole to either side at the top, like this:
This we repeated step by step, trunk by trunk down the whole line. And by the way, each week we added immense amounts of cuttings which required multiple carloads of thrip to the landfill, where they chipped and processed cuttings. Each trip looked like this:
And so the work continues. And as the motto most often associated with Benedictine vow of “conversion of life” , rursus incipiemus nunc et semper or, in simpler terms, “always we begin again.”