Science project calculates weight of tree

Warren County Middle School student Bliss Zechman tackled a weighty problem when she decided to scientifically determine the weight of a large oak tree on Hill Street, which, amid some controversy, had to be cut down several months ago when it threatened some critical Ben Lomand Telephone lines.

It all began, however, when Bliss expressed curiosity about the huge felled hardwood when she passed it in the company of her grandfather, County Commissioner Bill Zechman.

?It was a really big tree,? Bliss said, ?and there was a lot of history in it, so I just wanted to know about the size and mass of it.?

Like other local residents, Bliss wasn?t all that happy the great hardwood had to be cut down, but understood the reasons behind it.

?It?s kind of sad to see so much history go down,? Bliss said. ?But it was for a good reason. If you?re going to see a tree that big with that much history go down, it?s got to be for a good reason.?

It was after the tree had been cut down that Bliss talked with her grandfather about doing some research on it, since it offered a unique opportunity to examine a hardwood of that size right here in the city close to her own home.

Bliss decided to measure a large section of the tree, treating it as a cylinder for the purpose of measuring it and obtaining its mass and weight.

?We had to assume a certain shape,? Bill said. ?So we assumed the shape of a cylinder.

Bliss was aided in the measuring process by her willing grandfather, who devised a method to determine the density of the wood.

?He took a big piece of the original tree and had it cut into a precise square,? Bliss said.

The pair knew that there were technical sources where the specific density of oak could be obtained, like most any other material. But it was at this point the two ran into a bit of a problem.

?That?s where Charlie Bostick came in,? Bill said. ?He?s an expert wood-crafter, and I asked him to cut it into a 1,000 cubic centimeter cube, in other words, 10 centimeters on edge. A perfect cube. And he did a masterful job. It?s just exactly 1,000 cubic centimeters.?

Bliss and Bill then took the sample to Yorozu-America?s Morrison plant where its quality assurance department was gracious enough to provide a precise weight for the cube.

?The figures for oak are a broad average, and it is apparently for dry oak,? Bill said. ?Well, this was very green, so that?s why we got a piece of the actual tree, and literally calculated the specific density of this particular tree.?

Then the pair measured the tree itself, and though most of the limbs had been removed, they did get to measure a good portion of the trunk.

?The part we took the measurements from was a pretty large piece,? Bliss said. ?But it wasn?t the entire tree.?

?And it wasn?t a perfect cylinder,? Bill said. ?But it was close enough.?

Once the measurements were done, the pair calculated the mass of the huge oak cylinder in cubic centimeters, and multiplied that by the weight of the sample cube, coming up with the following estimates:

? Mass of log (pin oak, green): 15,393 kilograms, or 33,937 pounds

Though she was encouraged by her grandfather, Bliss undertook the task as a class project for science teacher Jeff Watson.

?He likes for us to do experiments and projects,? Bliss said. ?So I could do this for extra credit. My pop was willing to help, and I wanted to know about it, so it was a good thing for me to do.?

?She will be making a report to her class on how she did it,? Bill said. ?And she?s learning that this is what?s called the peer review process. In other words, you have your colleagues, who are knowledgeable about the same things, examine your methods.?

But grandfather admitted some of those methods were a bit unorthodox, since he and Bliss visited a local restaurant after having the sample cube weighed.

?We did some of the math on paper napkins at Taco Bell,? Bill said with a big grin. ?But we did the rest on a calculator.

All in all, Bliss was happy to come up with some information not everybody would know.

?I think my class will be pretty interested in how much it weighed,? she said.