LACEBARK PINE (Pinus Bungeana)

LACEBARK PINE (Pinus bungeana) By Kris R. Bachtell As those of us who enjoy working with plants settle in for another undoubtedly cold and long midwestern winter, we are more appreciative of plants like lacebark pine that offer their best ornamental features dur ing this time of year. Most of us turn to evergreens, both needled and broad-leaved types, when considering plants for winter interest. In addi tion to foliage, attractive bark should be one of the first features consid ered in the selection of useful "winter landscape" plants. Unlike many other ornamental features, bark becomes more prominent and visibile as trees become larger. Trees can be particularly attractive during the winter months when the low sun illuminates their bark. This, coupled with the contrast of snow and ice that frequently cling to the bark and limbs, can The bark of lacebark pine (Pinus create quite striking results. bungeana) is its most attractive fea ture. Specimens are usually multi stemmed. Ornamental Features Lacebark pine has perhaps the most attractive bark of any evergreen tree hardy in the Chicago area. Irregular whitish and cinnamon-brown patches develop all along the young, olive-green stems. On the trunk and larger limbs, these plates, approximately one- to four-inches in size, cre ate an affect that is somewhat similar to that of planetree (Platanus X aceri folia), a deciduous tree planted frequently in the eastern United States and Europe. However, the bark affect is even more striking on lacebark pine because specimens are usually multi-stemmed, with numerous branches originating from near the base of the plant. The two- to four-inch long needles of lacebark pine are medium to dark green and quite glossy. They are rather stiff to the touch and differ from those of most other pines. They are borne strictly in groups of three, rather than in groups of two, as with Austrian and Scots pines, or in groups of five, as with eastern white pine. The branchlets are reportedly somewhat brittle, although the Arboretum's specimens have not been particularly prone to breakage during ice storms. The cones are approxi mately two to three inches long, slightly less in width. 54 Observations in China Of all the plants we observed during the Arboretum-sponsored trip to northern China during the fall of 1990, the lacebark pine was one of the most impressive. It was the first plant we observed when we arrived at the Beijing International Airport. While surveying the airport grounds as we waited for our Chinese hosts to pick us up, we examined a group of these trees along the median between the terminal and the main parking lot. As we drove away from the airport, we observed numerous mass plantings of lacebark pine along our way. Throughout the Beijing area, lacebark pine is a popular landscape tree, and the mass plantings may have been nurseries to provide plants for other areas of the city. At several of the historic temples we visited, lace bark pine was planted in prominent locations, often bordering busy pedestrian walkways. It is so popular in Beijing that we even found it planted in small sidewalk containers in front of major department stores. Due to extensive deforestation, it is not nearly as common as a wild plant as it once was. We observed remnant native populations in pre This early rendition of lacebark pine serves, temple grounds, and in locations where the terrain was too depicts the unique, stiff needles that treacherous to harvest trees for lumber or to cultivate the land for crops. distinguish it from most other pines. Lacebark pine persists in remnant native populations in China. This is an early photo by E. H. Wilson, who col lected plants in western China for the Arnold Arboretum in 1907-1910. 55 We observed plants and collected seed from a large population of lacebark pines in Shanxi province, a few hundred miles southwest of Beijing, on the Mountain of the Heavenly Dragon. It occurs at an elevation of 5,000- 5,500 feet, on the southwest-facing flank of the mountain, co-dominant with Oriental arborvitae (Thuja orientalis) and Chinese hard pine (Pinus tabulaeformis), both on gentle slopes and around the cliffs. Landscape Use Lacebark pine has proven fully hardy in the Chicago area and in Madison, Wisconsin. As with most pines, this species grows best in well drained soils and full sunlight. Siting it in poorly drained soil or flood prone sites can be lethal. Flooding during 1987, in the Woody Plants of China collection on the Arboretum's east side, killed one of the two oldest specimens at the Arboretum. The other specimen is declining and may die. With the valuable insight into its native habitat that we gained in China, we recently planted new specimens in locations that should prove more favorable for healthy growth. Despite becoming a large tree when mature, lacebark pine grows slowly enough, usually less than a half a foot each year, for it to be consid ered for residential use. The ailing, flood-damaged, 39-year-old speci men at the Arboretum is just 17 feet tall. Because of this slow growth, one must wait patiently for the attractive bark character to develop. This fea ture does not usually develop until the plant surpasses six feet in height. The uniform oval habit of young and middle-aged specimens further justifies the use of this tree in residential landscapes. The ascending branch structure limits the spread of the plant and makes it useful at the corner of a residence, as a specimen in a shrub border, or as a patio tree. When used as a patio plant, the lacy bark can be observed closely throughout the year. The form remains oval until the tree exceeds 25 feet in height. Older, maturing specimens tend to become more rounded, as the weight of branches causes a more horizontal orientation to the limbs. Several specimens observed in China that our guides said were several hundred years old were over 40 feet in height, with an even wider spread. In the United States, lacebark pine is still quite rare. Most large speci mens are located in arboreta, botanical gardens, and on university cam puses. Both the Morris Arboretum in Philadelphia and the Ohio State University campus in Columbus have magnificent old specimens. The Chicago Botanic Garden has a young specimen well-sited in the Krasberg Rose Garden that is beginning to develop the showy bark character. Locating locally grown trees for purchase in the Chicago area is some what difficult. Only a few nurseries in northern Illinois offer lacebark 56 pine, although a number of specialty conifer growers on the west coast grow this plant. Your local garden center could special order a plant for you. With careful, proper siting of young lacebark pines in the Arboretum, their outstanding bark character will develop for all interested visitors to view and enjoy. This magnificent specimen of lacebark pine is growing at the Morris Arbore tum in Philadelphia. 57 .

Load more