On the edge of Marjorie’s garden grows a red oak. Twenty feet high and nearly as broad across its widest branches, I have watched it double in size since first meeting this garden seven years ago. And while it is still a young tree, the trunk’s bark smooth from top to bottom, this year there is a crop of acorns. We are watching them fill out, wondering how many will reach full size, and provide winter mast for the squirrels. No doubt, it was a squirrel that started it all.

The red oak is transforming the garden. The nearby perennial bed, once considered suitable only for full-sun plants, gets shadier each year. Spruce and fir that crowd the oak from behind are removed. Everything that can be done to accommodate the future of this oak, we do.

In November 2004, Congress passed legislation that designated “The Oak” as our national tree. This act reflected a four-monthlong vote hosted by the National Arbor Day Foundation on its Web site. The oak was the people’s clear choice from the start, finishing with more than 101,000 votes, compared to almost 81,000 for the runner-up, the redwood. Other popular trees were the dogwood, maple and pine.

My question, as I reflect on the red oak in Marjorie’s garden, is just what plant did Congress have in mind? With more than 60 species of oaks in the United States, how is it possible to designate the entire genus, i.e. “The Oak,” as our national tree? Citizens in different regions of the country will have entirely different trees in mind when thinking about “The Oak.” Should not our national tree be a distinct species known to every citizen, like the bald eagle, our national bird?

Being specific was an easier task at the state level. The white oak (Quercus alba) got the nod in three states, Connecticut, Maryland and Illinois. Georgia chose the live oak (Q. virginiana), while the District of Columbia elected the scarlet oak (Q. coccinea). And New Jersey picked the red oak (Q. rubra). Only one state, Iowa, opted to designate oaks in general as the state tree. However, in the National Grove of State Trees (Washington, D.C.), it is the bur oak (Q. macrocarpa) that grows for Iowa.

There is no oak species native to all regions of the country. Is there then a common thread, a single characteristic that comes to all minds when thinking about “The Oak”?

The strength and durability of most oak species must be that common thread. Connecticut’s choice was inspired by the Charter Oak, already an old and hollow white oak when Connecticut struggled for its rights as a new colony. Maryland’s Wye Oak had lived for 460 years, longer than Maryland had been a state, when it fell during a thunderstorm in 2002.

I recall live oaks from my Georgia boyhood, their long horizontal branches thicker than the main trunks of most trees, long gray beards of Spanish moss flowing from every limb. The wood of this evergreen oak is heavier than any other North American tree.

If the National Arbor Day Foundation decides to hold a run-off election to decide which species of oak should represent the nation, I suspect Mainers will cast their votes for the red oak, like the one in Marjorie’s garden. We are planning to retire under the shade of this tree, to be a part of its history, a story that we hope will continue long after we are gone.

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