Michael J. (Mike) DeMarco is a City of Watertown Planner through the Office of Planning & Community Development. Mike is also a Council Board Member, an ISA Certified Arborist, and a 2017 Municipal Forestry Institute (MFI) graduate. These stunning winter scenes from his Instagram page prompted us to ask him about Watertown’s Washington Street Arboretum, soon to be renamed the Downtown Arboretum.
The pictures were taken in front of the Roswell P. Flower Memorial Library, along Washington Street within the City’s Downtown Arboretum. In the foreground of these two night-time photos are ‘Glenleven’ littleleaf lindens (Tilia cordata), a sugar maple (Acer saccharum), a ‘Summit’ green ash (Fraxinus pensylvanica), a ‘Red Sunset’ red maple (A. rubrum ‘Red Sunset’) and a saucer magnolia (Magnolia x soulangeana). In the background of the pics are some of the more unique and historic trees found within the arboretum (read on!)
Each year, members
of the Society of Municipal Arborists (SMA) vote for the SMA Urban Tree of the
Year. Praise for this year’s winner, American hophornbeam (Ostrya virginiana),
came from fans in states as far-flung as Wisconsin, New York, Virginia, and Texas.
Here, we hear from
the Council’s Dr. Nina Bassuk at Cornell and from her colleague, Dr. Eric
Wiseman at Virginia Tech. You can see the full list of SMA Urban Trees of the
Year going back to the program’s inception in 1996 here.
Tree of Merit: Overcup Oak (Quercus lyrata) Story by Cene Ketcham, Extension Arborist, Casey Trees
Overcup oak (Quercus lyrata)—sometimes known as swamp post oak or water white oak—is a tough shade tree in the white oak group. Though it can sometimes be difficult to source, its popularity for use along streets and in the landscape has been increasing—a testament to the growing interest in this species. At first glance, overcup oak is sometimes confused with swamp white oak (Q. bicolor), post oak (Q. stellata), or with its close relative, bur oak (Q. macrocarpa). Although it shares some attributes with these species, closer inspection reveals a tree with a character all its own.
Story and photos by Cene Ketcham, Extension Arborist, Casey Trees
Hophornbeam (Ostrya virginiana) is an attractive small to medium tree with big urban credentials. However, compared to other urban-tough trees like red maple, ginkgo, and honeylocust, hophornbeam has been regrettably underutilized.
Sometimes called “ironwood” like its bottomland cousin, Carpinus caroliniana, hophornbeam’s hard, dense wood makes it highly resistant to damage from wind, snow, and ice. Largely insensitive to site conditions, it takes indignities like air pollution, compacted soils, and droughty conditions in stride. Hophornbeam grows well in full sun to part shade, needs little pruning, and is generally free of insect pests and diseases. An excellent street tree in warmer climates, hophornbeam is intolerant of salt so should be avoided where road salting is common.
Regal Prince is the trademark name for Quercus x warei ‘Long’, a narrow, upright hybrid of fastigiate English oak (Quercus robur f. fastigiata) and swamp white oak (Quercus bicolor). Its leaves are clearly intermediate in shape and are glossy and leathery like those of swamp white oak. In Ithaca, Nina Bassuk and Andy Hillman first planted Regal Prince in 2005, and the oaks have performed well there ever since.
“It’s a good tree for tight spaces—not a shade tree as such,” says Cornell Urban Horticulture Institute Director Bassuk. “It has the shape of the fastigiate English oak but is more tolerant of poor drainage and is mildew resistant, unlike Q. robur. It also tolerates a higher pH than does straight Q. bicolor. During last summer’s drought its foliage stayed green throughout so it appears both wet and dry tolerant (after establishment of course).”
Some blog posts resonate long past their original publication date date. Transplanting and a Deeper Look at “Fall Hazards” was one of the top five posts in 2015 and was the second most viewed post in 2016. Former NYC Director of Street Tree Planting Matt Stephens and Taking Root Editor Michelle Sutton coauthored this story questioning commonly held beliefs about “fall hazards,” mostly as it applies to B&B trees, but they also discuss the interaction of the fall season with other production methods, like bare root. Nina Bassuk helped craft the section called “The Five Branches of Transplanting Success,” which should be of interest to anyone planting trees.
Kristy King and NYC Forest Restoration: Dreaming Big for the City’s Natural Areas Many readers wanted to learn about the work of the NYC Natural Resources Group, which manages 5,000 acres of forested natural areas across the five boroughs of NYC, and about Director of Forest Restoration Kristy King. Her dream for NYC: “… that all forested areas are dominated by native species and that invasive species have been managed to the point that natural forest regeneration is occurring and that the public holistically values the natural resources in their area.”
NYSDEC Urban Forestry Intern Jennifer Kotary: Get to Know Her! Many blog readers were keen to know about this dynamic up-and-comer. “My internship research involved in-depth exploration of what communities are doing to protect and build green infrastructure across the state. Via Mary’s [Kramarchyk] assigned projects, I was able to produce tangible evidence that there is quite the statewide collective will to plant and nurture an expanding canopy as well as many career and volunteer opportunities to do so.”
SMA’s 2016 Urban Tree of the Year: Musashino Zelkova generated a lot of buzz. ‘Musashino’ has been a successful and popular street tree for many more years in Japan, proving itself useful as a narrow, upright form of zelkova. It can tolerate drought and heat and is pH adaptable and pollution tolerant. See a list of all the past SMA Urban Trees of the Year here.
Gary Raffel: Get to Know Him! Gary has served the Council in a variety of capacities, including as a board member. “I started Dynamic Tree Systems in 2002, offering general tree care service as well as Plant Health Care and Integrated Pest Management programs. I later wanted to find a niche in the industry and purchased a Tree Radar Unit at a time when there were only three of us in the U.S. and eleven people in the world using the equipment. A few years later I became the company’s international trainer, such that when a new unit was sold I would fly to the particular client and spend a week training them on their new equipment (I still do that, in addition to Dynamic Tree Systems).”
The 2017 Society of Municipal Arborists Urban Tree of the Year is native to much of the Eastern United States. Hikers from New York to Tennessee who ascend to dry ridges will often see the deeply furrowed, blocky barked trunks of chestnut oak (Quercus montana) (syn. Q. prinus). The bark is so distinctive, it may be the only ID feature one needs.
There’s growing interest in using chestnut oak in the urban environment because it is pH-adaptable, handles dry soils and periods of drought, has a beautiful mature form, requires minimal pruning, and tends to be free of major pests and diseases.
The common name “chestnut oak” owes to the leaves looking like those of American chestnut (Castanea dentata) and indeed both are members of the beech family, Fagaceae. Other common names for chestnut oak include rock oak, rock chestnut oak, or mountain oak—referring to its customary sighting in dry, rocky soils on ridgetops, where it has a competitive advantage. However, if chestnut oak is open-grown in the moist, well-drained soil that all trees dream about, it will be significantly bigger than its scrappy ridgetop cousins. Typically it reaches 50 to 70 feet (15 to 21 m) tall and almost as wide. It’s hardy in USDA Zones 4 to 8 and prefers full sun.
The Society of Municipal Arborists (SMA) has voted Zelkova serrata ‘Musashino’ the 2016 Urban Tree of the Year. The yearly selection must be adaptable to a variety of harsh urban growing conditions and have strong ornamental traits. It is often a species or cultivar considered underutilized by urban foresters. The SMA Urban Tree of the Year program has been running for 20 years, and recent honorees include yellowwood (2015), ‘Vanessa’ parrotia (2014), and live oak (2013). You can see the full list of past winners on the SMA website, www.urban-forestry.com.
Zelkovas are native to Japan, Korea, and Taiwan. J. Frank Schmidt & Son Co. introduced Zelkova serrata ‘Musashino’ to the North American nursery trade in 2000. Named after a city in Tokyo (which itself is a city but also a prefecture containing multiple other cities), ‘Musashino’ has been a successful and popular street tree for many more years in Japan, proving itself useful as a narrow, upright form of zelkova. It has the genetic potential to reach 45 feet (14 m) in height and 15 feet (4.6 m) in width at maturity. It is hardy in USDA Zones 5 to 9.
… and it’s one that’s close to our hearts, in the sense that the Tree of the Year (TOY) is none other than the one featured in bloom in our blog’s banner up top, yellowwood (Cladrastis kentukea). What serendipity!
Surrey, BC Urban Forester Emily Hamilton, who attended NY ReLeaf last summer at Hofstra before she relocated to Canada, wrote a column earlier this year in City Trees about yellowwood. Hamilton wrote:
Like me, you may have a dog-eared, well-worn copy of the Urban Horticulture Institute’s (UHI) Recommended Urban Trees: Site Assessment and Tree Selection for Stress Tolerance. Another fantastic resource for urban foresters and UF volunteers that has just been updated is the Cornell Woody Plants Database.
Nina Bassuk says, “What makes the site unique is its focus on matching woody plants to site conditions, a feature sometimes lacking on other plant selection sites and a consideration that is sometimes lost in the design and plant selection process.” With its extensive image collection and cultural information, the site is also very useful for woody plant ID and study.
Each entry includes ultimate size and shape, USDA Hardiness Zone, light requirement, salt tolerance, moisture tolerance range, insect and disease considerations, and key ornamental features. Impressively, each entry has Nina voicing a short audio lesson that reinforces ornamental and ID features. Nina says this is a work in progress, as she is re-recording some of the entries for better audio quality.
There is a Course Plant Walk section, which you can use to find a series of plant walks through the beautiful Cornell campus based on different criteria like species (e.g., oaks, maples, and rosaceous and flowering trees) or tolerances (e.g., dry site and wet site trees); click on Maps to see the walk route.
The database was originally the outgrowth of the year-long joint Horticulture/Landscape Architecture (LA) course, “Creating the Urban Eden,” taught by UHI Director Nina Bassuk and Dept of LA Chair Peter Trowbridge.
The site had modest beginnings as an “online textbook” circa 2000. The first version consisted of a FileMaker Pro database running on the Cornell network from a Mac under a desk in the main offices of the Department of Landscape Architecture. Since then, the site has grown significantly more sophisticated with three major revisions that added additional features and functionality. The most recent upgrade was supported by a SUNY Innovative Instruction Technology Grant in 2013.