Everybody knows at least the first line of Longfellow’s poem about the village blacksmith: “Under the spreading chestnut tree, the village smithy stands.” But many may not be aware that the chestnut tree has gone the way of the elm, wiped out by blight.

The mighty chestnut trees, close to 100 feet tall, once flourished from Maine down to Alabama. They shaded the streets of cities and towns. They produced more lumber than any other species in the Appalachian forest. Their nuts provided food for deer and other animals and, toasted, offered a treat for humans.

No more. Starting in the early 1900s, a fungus brought in from the Far East and first noticed in New York City in 1904, spread gradually through the country. Within 50 years, most chestnut trees in the country had been killed by cankers or sores that blocked the flow of water and nutrients up the trunks.

But cheer up. After years of trial and error scientists have hit upon a cross-breeding method that will eventually produce trees that combine the blight resistance of Chinese chestnut trees, which resist the fungus but are short and less attractive, with the strength and beauty of the American variety.

A second approach also shows some promise. Italian and French scientists have developed a new class of viruses, called “hypoviruses,” which attack the fungus, in a case of one disease killing another disease. Still another method being tried employs a bacterium that can attack the fungus.

A few old-growth chestnut trees, including about 200 in Maine, remain standing, in isolated areas where they have escaped the blight.

The breeding effort is being led by the American Chestnut Foundation, a privately funded nonprofit organization devoted to restoration of the American chestnut. It is growing and cross breeding chestnut trees on a 130-acre tract in southwestern Virginia.

Here in Maine, Glen Rae, a forester turned stockbroker, heads a chapter of the foundation. It operates 10 orchards in the Camden-Augusta area, where 2,000 trees are in the fourth generation of cross breeding, as well as a forest in Veazie. It takes six generations to achieve successful resistance. The University of Maine and the U.S. Forest Service have just permitted the foundation to grow chestnut trees on a plot in the Penobscot Experimental Forest at Bradley.

Authorities agree that it will be 10 to 15 years before enough blight-resistant chestnut trees are produced to permit widespread replanting.

When that happy time arrives, cities, towns and individuals can start bringing back the beautiful towering trees that Longfellow made so famous in an earlier day.