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The Wreck of the 3230
Photos By Rich McManus
At about 2:33 p.m. on May 4, the second largest tree on the NIH campus was felled by workmen after it had been determined that the 100-foot specimen already the subject of various modes of tree-doctoring was in danger of collapse. The massive tulip poplar, located in a valley between Bldg. 15K and the on-campus houses of various NIH officials, could have been expected to shake the ground when it fell, but it did not; the tree was rotted to the core, and essentially hollow.
Lynn Mueller, who directs grounds maintenance for the Office of Research Facilities, chronicled the tree's decline: "During our yearly winter inspections of the campus trees, William Scofield discovered that the core wood in tulip poplar #3230 had severely declined with extensive rot (see NIH Record, June 10, 2003, for a story on Scofield's diagnostic expertise). The tree was in danger of collapsing, especially once it had leafed out, adding weight and wind resistance. Removal was also timed to be before birds nested and after squirrel babies were able to fend for themselves. No bird nests were found, but a squirrel nest was discovered. The climbers allowed five juvenile squirrels to escape before the upper limbs were removed.
"Since the rot of the trunk was extensive with the center totally void, we were unable to count the rings to determine its age," Mueller continued. "The tree trunk was 63 inches in diameter and 15' 8" (188 inches) in circumference and approximately 100 feet tall, making it the second largest tree on campus. A tree that size may be between 100 and 125 years old.
"Tulip poplars (Liriodendron tulipifera) grow exceedingly fast compared to oaks and that makes them generally more vulnerable to rot and storm damage," said Mueller. "It was not a Montgomery County champion, as that tree is 293 inches in circumference. The Grounds Maintenance and Landscaping Team, ORF, had performed numerous prunings and preventive maintenance work on the tree over the years, including installing steel cables between large branches to help share the stresses of weight and wind."
Workers some four decades ago had also tried cavity-filling in the belief that filling trunk cavities would stop further decay and strengthen the trunk or limbs, said Mueller. "Today's knowledge says to prune away or leave such injury or cavities alone as a healthy tree may compartmentalize the injury or disease and go on with living or, if not, fall into further decline," he noted.
During the 1950's and 1960's, various materials were used as hole-fillers including concrete, concrete blocks and a hardening liquid foam, Mueller explained. But all eventually failed as they tended to hold moisture, he said. "This tree had the hardening foam. Such fillers then present a disposal problem when the tree is taken down."
Mueller added, "Our largest tree on campus by circumference and spread is a red maple, tree #2315, located along Rockville Pike where the small stream goes under the highway. That tree is 210 inches in circumference, 117 inches in diameter with an approximate crown spread of 65 feet. It may well be over 100 years old too."
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