It’s enviro vs. enviro in Washington’s most “progressive” suburb, Takoma Park. Indeed, the Washington Post reports, “a potentially bough-breaking debate between sun-worshipers and tree-huggers.” That is, which is more environmentally desirable, solar power or tree cover?

The modest gray house in Takoma Park was nearly perfect, from Patrick Earle’s staunchly environmentalist point of view. It was small enough for wood-stove heating, faced the right way for good solar exposure and, most important, was in a liberal suburb that embraces all things ecological.

Or almost all. When Earle and his wife, Shannon, recently sought to add solar panels to the house, which they have been turning into a sustainability showplace, the couple discovered that Takoma Park values something even more than new energy technologies: big, old trees.

When they applied to cut down a partially rotten 50-foot silver maple that overshadowed their roof, the Earles ran into one of the nation’s strictest tree-protection ordinances. Under the law, the town arborist would approve removing the maple only if the couple agreed to pay $4,000 into a city tree-replacement fund or plant 23 saplings on their own.

So now the rival environmentalists are squaring off in front of the city council:

Takoma Park City Council members, who are considering revising the 1983 tree-protection law, listened Monday night as otherwise like-minded activists vied to claim the green high ground.

Tree partisans hailed the benefits of the leafy canopy that shades 59 percent of the town: Trees absorb carbon, take up stormwater, control erosion and provide natural cooling….

Solar advocates at the hearing said that they are tree lovers, too, but that scientific studies support the idea of poking select holes in the tree cover to let a little sun power through.

Being an environmentalist homeowner can become a full-time job:

But even some veteran solar users don’t like the idea of trading trees for panels. Mike Tidwell, founder of the Chesapeake Climate Action Network, installed solar panels on his Takoma Park house 10 years ago. As the trees have grown, the panels’ effectiveness has diminished, and Tidwell now buys wind power credits to supplement them.

Still, he said, “I don’t believe you should cut down trees for solar.” Rather, he thinks neighbors should work together to place shared panels on the sunniest roofs.

The city’s “official arborist” turned down Earle’s application to tear down one rotting tree to accommodate his solar panels. Now the council is debating the issue.

The Earles’ council member, Josh Wright, said he was sympathetic to their plight. He said it should remain hard to cut down a tree, but he’d like to see a break for people installing solar power. Wright also wants all homeowners to get credit for trees they may have planted in the years before they remove a tree.

It all sounds very complicated. And who knows what the right answer is? Or if there is a right answer? Or if the right answer might change next year?

And that’s where property rights come in.  They allocate both jurisdiction and liability over scarce resources, like roofs, trees, and access to sunlight.  A little “law and economics” can help to understand the Takoma Park Tree Tussle.  Nobel Laureate in Economics Ronald Coase, who just turned 100, brought law and economics together to study the way that people externalize costs (make others pay for them) or internalize them (take them into account when making decisions).  When property rights are well defined and legally secure, and rights can be exchanged at low cost, resources will be directed to their most highly valued use.  In fact, the initial allocation of property rights doesn’t affect the allocation of resources, if the transfers are freely and easily negotiable.

That, unfortunately, is no longer the case in Takoma Park, where instead of a fairly straightforward transaction (facilitated by a purchase), there is a tussle over ill-defined rights and obligations that have little or no legal security, in a very expensive and costly process of negotiation that will almost certainly consume more wood pulp for memos than is contained in the tree in question.  Well-defined and legally secure property rights save us the rather substantial trouble of sitting down like the Takoma Park City Council and trying to judge the advisability of every proposed purchase, all the while consuming large amounts of paper and exuding large amount of hot air.