The project showcased in the last post continued this week, with the bare-root transplanting of five London Plane trees (Platanus x acerifolia) and a mature crabapple. Again, Matthew R. Foti Landscape and Tree Service was the prime arborist on this site in a Boston suburb — but this week the Foti crew was joined by Mike Furgal, who was the first arborist to use the air tool for bare-rooting trees in this way.
Mike has been doing this work a bit over five years, and his expertise was the basis for the bare-root workshop sponsored by the Massachusetts Arborists Association and hosted by Matt last August. Neither arborist had moved this many trees of this size — the London Planes ranged from 11 inches dbh to 13″ dbh — and in teaming up they brought all their knowledge to bear to the challenges of this particular project. (The homeowner figured she had hired the A team, given the pair’s depth of knowledge and breadth of experience.)
I took a lot of photos during the first day, and returned today to shoot more. My colleague Bruce Jones and I also shot extensive videotape of the process, which is currently in editing, and will explain the sequence of bare-root transplanting using compressed air (watch this blog for word that it’s done and available).
To avoid computer-use burnout (mine), I’m posting one batch of photos today, and will add another post with more in a few days. I promise, this first batch of images will be plenty to digest for a while….
The site before the five London Planes get moved. The first tree to be excavated and moved is the one furthest from the camera, just to the right of the white trailer. These trees flanked a driveway; in this photo the driveway asphalt has been taken up and the gravel base has been partially removed. Trees are located 3-4 feet from the drive edge.
The mini excavator has dug a partial trench; the trench must be dug in sections, or it would be too difficult to reach in and haul out the blown soil. A climber is in the tree, tying in lines to be used later during transport.
Bare-rooting has begun, and one pigtail of roots is already tied to the tree's trunk. The tree did not extend any roots into the gravel driveway base, so it only has 3-4 feet of root mass on that side. It did extend its roots out parallel to the driveway, and radially out into the lawn. A good depth of soil also let it sink its roots quite deep -- 2-3 feet -- into the ground. Mike Furgal is in the green jumpsuit and facemask.
Pigtailed roots, and short roots along the driveway edge.
Good deep soil, good deep roots -- everywhere but at the gravel.
Lots of activity at the tree: two air-tool excavators, an mini excavator digging the trench, a Bobcat taking soil away, and Matt Foti assessing progress.
Blowing out soil, getting closer to the move.
Padding the trunk with layers of burlap for the move.
Giant forks have been run under the tree, and the loader is getting ready to lift it. Four taglines are visible in this shot; they won't prevent the tree from falling, but help indicate how it is balanced during the move.
Lifting and backing, slowly and very carefully.
A pause for the forks to be positioned more firmly.
Big machine, bigger tree. The root plate on this tree extended about 18 feet across at its maximum width. Transporting a large, upright live tree is a slow-speed operation.
Compare this root plate to that of a B&B tree, or a tree-spaded one (though this tree is too large for a tree spade), and it's clear what an advance this technology promises to be in benefiting the health of trees to be transplanted. The tree's energy reserves are largely stored in the roots; save the roots, reduce stress on the tree, and speed re-establishment after planting.
The tree, post-planting. The arborists assessed how deep the root mass was and how it was formed, and dug the planting hole to accommodate, roughly, its form. Once the tree is placed in the hole, the roots are spread out radially by hand, and loam shovelled in around, under, and over them. Watering starts during the digging process, once the tree has been levelled, so that a loam slurry anchors the root plate and tree to its new site. A well is formed to retain moisture and more water is added.
Two to four inches of mulch is added around the tree, and kept away from the trunk.
Minor pruning to fix a lamppost-branch conflict.
The transplanted tree seven hours later, in its new home.
Matthew R. Foti Landscape and Tree Service, Lexington, MA – lead arborist
Furgal Tree and Landscape, Northborough, MA – consulting arborist
Robert Hanss Inc. Landscape Construction — landscape contractor
Reed Hilderbrand — landscape architects (Chris Moyles, project manager)
Deborah Howe
Taking Place 
Training crews to this method should be essential. And as the technique is refined, the work should go faster. How does the cost of moving a tree this way compare with other conventional transplanting routines?
This is astonishing. What is the mortality rate, over the 5 years that M.F. has been doing it? Did he need to obtain special vehicles for the move? Water source? Should one try this when hurricanes are likely to happen?
Cost depends on the size of the tree and conditions under which it needs to be moved — that is, how much machinery and how much labor will be required. Trees as large as these London planes would be unmovable with a tree spade; a B&B move would involve machine-digging, root pruning for clean cuts on damaged roots (which the air-tool excavation required as well), burlapping and drum-lacing, and then the move and transplanting. It’s very labor-intensive, and requires heavy machinery, because you’re moving a lot of soil as well as the tree itself.
My Lawn and Landscape article describes a cost comparison in which any kind of method is usable:
“Hand-digging to get a B&B tree usually requires a backhoe, a fork and a crew of two or three to dig, burlap, tie and move each tree. With the care and machinery needed to transplant this way, hand-digging tends to be the slowest and most expensive method of transplanting a specimen ornamental tree.
A tree spade takes less time than either hand digging or air spade bare-rooting, but it does require a tree spade, which is an expensive piece of equipment. Air spade transplanting takes longer than tree spading, but equipment costs for a compressor and an air spade tend to be much lower.
Furgal, who has done most of his transplanting from one location on a site to another, believes that an on-site bare-root move might cost half as much as a move using a tree spade, because more heavy equipment is needed with the tree spade. However, the need to move a tree from one job site to another may change the equation somewhat.”
Matt Foti had all the machinery he needed — a Bobcat, a mini-excavator, a large front-end loader with oversized forks, and air compressors — a smaller operation would likely rent some or all of the equipment necessary. Water would come either from an arborist’s watering truck or from the client’s property.
As for hurricanes: that depends on the site conditions also, and the type of tree and its root system, but the better part of valor — discretion, that is — might suggest that this kind of transplanting be done not during hurricane season in a hurricane-prone and unsheltered area. That’s a question that would best look at conditions specific to a particular tree, client, and acceptable threshold of risk. (The anchoring provided by a tree’s own root system and the thoroughly watered backfill usually is sufficient to hold the tree upright in ordinary conditions; should the tree have been growing crooked or with a lean, or on a slope, then guying may be necessary.)
Lots of good information here Deb, I will be citing this work in my “work by others” section for my talk. I will make sure all the proper credits and sources are cited.
Cheers,
Stan
Thanks, Stan — happy to be of help!