City Trees

The 2018 SMA Urban Tree of the Year is native to much of the Eastern United States. It's cold hardy to Zone 4 and heat hardy to Zone 8b or 9. It is the majestic tulip tree (Liriodendron tulipifera), reaching 60 to 90 feet (18 to 27 m) in height and 30 to 50 feet (9 to 15 m) in width at maturity. It's named tulip tree because of the shape of its leaves, which emerge first, and its showy flowers, which follow and can be borne higher up in the canopy and partially hidden from view by the leaves. Liriodendron is Greek for "lily tree" (leirion is Greek for "lily" and is Latinized to "lirio," and dendron means "tree") and tulipifera is Latin for "tulip-bearing." So one could say it's a "tulip-bearing lily tree," although the reference to lilies is not well understood—the tree is in the magnolia, not lily, family. In the plus column, tulip tree is fast-growing and beautiful; offers great wildlife value; tolerates acid soils, somewhat alkaline soils, and soils that are occa- sionally wet; can grow in partial sun; and has very good disease and insect resistance. It is readily available in the trade, and there are more compact cultivars available, like 'Emerald City' from J. Frank Schmidt & Son Co. ( Here's a delightful video with Frank Warren and Michael Dirr as they discuss 'Emerald City' and tulip tree generally). In the minus column, tulip tree is not tolerant of salt spray or soil salt; it can be sensitive to both drought and chronically poor soil drainage; the straight species needs a large soil volume to meet its needs as a large-maturing shade tree; and it can be weak-wooded and drop a lot of branches, especially after ice storms. If used in urban environments, the most successful planting sites for the straight species will be places like parks, parkways, rights-of-way, or extra-wide medians with shared soil volume. Compact and fastigiate cultivars will need less soil volume. Dublin, Ohio Assistant Forester Jocelyn Knerr is a fan. "I nominated the tulip tree primarily because it's a native tree to Ohio, which makes it suited to our climate as well as being good for our wildlife. We started planting the tulip tree ten years ago in Dublin, mostly in rights-of-way. Their present diameter at breast height (DBH) is Michelle Sutton has been Editor of City Trees since 2005. 10 inches (25 cm) and they are a good 35 to 40 feet (11 to 12 m) tall. We just recently started planting the upright cultivar 'Fastigiatum' in parking lots; we will see how they do there. The tulip tree has become a resident favorite because of its attractive leaf shape and flowers as well as its bright yellow fall color." The SMA recognizes the underutilized, attractive, and useful tulip tree for its service to urban forests and encourag- es its use when matched appropriately to site and as part of a diverse urban tree inventory. You can see the full list of past Tree of the Year winners on the SMA website, www.urban-forestry.com Announcing the 2018 SMA Urban Tree of the Year by Michelle Sutton, Editor, City Trees 26 CityTREES

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