City Trees

January/February 2011

City Trees is a premier publication focused on urban + community forestry. In each issue, you’ll learn how to best manage the trees in your community and more!

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leaving as full a crown as possible.” In order to accomplish this objective, she could write specifications like the fol- lowing {with author notes}: “All pruning shall be performed in compliance with A300 Standards and the following specifications {specifications may vary by species}: • Clean the crown; remove dead branches 3⁄4 inch diameter and larger {if we simply say “remove decayed branches,” any branch with a cavity can be removed}; remove diseased infested branches 1 inch diameter and larger {be specific about the disease(s) or do not use this phrase – e.g., powdery mildew is a disease but we wouldn’t want all branches removed}; remove weakly attached branches 1 inch diameter or larger; and remove the weakest or most damaged branch of a pair or group of rubbing branches 1 inch diameter or larger {Most of the branches in a tree are crossing, so specify “rubbing” to target injured branches}. • Thin by removing branch clusters in the outer third of the crown that either grow downward or cause the growth habit of the branches to grow below the horizontal. • Raise by removing any low branches that will obstruct vehicle or pedestrian traffic— specifically, provide 7 feet 6 inches over the sidewalk, 10 feet 6 inches over the parking lane or driveways, and 12 feet 6 inches over the travel lane, except truck routes which will require 14 feet 6 inches. • Remove 15% of the total live foliage or buds from each tree.” {Note that if we say “Do not remove greater than 15%,” the tree worker can remove 5% and be in compli- ance with the specifications. If we say, “Remove between 10% and 20% of the live foliage,” the tree worker can remove 10% and be in compliance. If we want a spe- cific target, we should state that percentage. Whatever the desired outcome, the language of the specification should be unambiguous.} If the agency has specific limits on work or a specific tree needs special attention, we can include an addendum— for example: • Do not remove any branches greater than 4 inches in diameter without first receiving approval from the proj- ect arborist. • The pruning cuts on live foliage will be made in the outer third of the crown and typically on branches 2 inches in diameter and less. Retain all interior branch sprouts. • The tree closest to the parking garage must have the west side of the crown pruned to clear the building and security camera. The typical cut will be 3 inches in diam- eter and will be made at the nearest live lateral to the trunk on the building side. This tree will have 20% of the live foliage and buds removed to accomplish this task.” Using “Before” photos of the trees, you will be able to tell 20 if these specifications are being followed. By checking the location and size of cuts, you can inspect if the pruning is being performed to the specifications. In some situations, such as a declining oak, you may not want to remove any live foliage. In other trees, the foliage density may be a challenge to calculate. However, with a full crown, if you are within 5% to 10% of the estimate, you are probably getting as close as reasonably possible. I have both received and performed contracts with oral specifications made while walking and discussing the subject trees. There needs to be high trust and confi- dence when using oral specifications. When performing the work, I prefer written specifications. When contracting out work, I use written specifications for bid proposals and consistency in bid evaluation. The cleaner and tighter our bid specifications are, the easier it is for the contrac- tors to bid and the inspectors to evaluate the work. I am willing to review bid specifications and provide com- ments for SMA members following A300. Please allow reasonable turn-around time. You may forward copies to Set standards high! Remembering SMA Founding Member Earl Blankenship Remembering SMA Founding Member Earl Blankenship On November 24, 2010 Earl A. “Pat” Blankenship of Springfield, Missouri, passed away at St. John’s Hospital in Springfield. He was 86 years old. Earl Blankenship was a founding member of the SMA and a member of the International Shade Tree Conference. He served as the SMA’s second President (1967-1968). Earl was City Forester for the City of Pittsburgh from 1955 to 1975. After retirement from the City of Pittsburgh, he ran his own business, Earl Blankenship Tree Service, in Pittsburgh. Son Damon says, “He really enjoyed the company of those who were dedicated to the profession of caring for trees—friends like Ed Scanlon, Paul Heintzman, and many SMA members, especially his fellow founding members.” We wish to acknowledge Earl for his service to SMA and to our industry, and we send our condo- lences to Earl’s family. For additional information please contact Earl’s son Damon Blankenship at: City Trees

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