In their classic textbook “Understanding Poetry,” Cleanth Brooks and Robert Penn Warren begin their discussion of Joyce Kilmer’s “Trees” by writing: “This poem has been very greatly admired by a large number of people. The fact that it has been popular does not necessarily condemn it as a bad poem. But it is a bad poem.” It is so, they conclude, because, “[T]he tree, as opposed to the poem, is lacking in meaning and expressiveness; it has those things only insofar as man can give them to it.” Lee Friedlander (b. 1934) knows trees, and he knows art, and in the 36 black-and-white photographs included in “A Ramble in Olmsted Parks” at the Metropolitan Museum of Art, he grapples with the high task of imposing meaning and expressiveness on nature.

Mr. Friedlander’s work is totally without the sappy sentimentalism that inflicted that phrase, “I think that I shall never see / A poem lovely as a tree,” on generations of innocent schoolchildren. But whereas Kilmer’s tree is vague, the mere notion in his head of a generic tree, Mr. Friedlander confronts real trees in the settings prepared for them by the great 19th-century landscape architect, Frederick Law Olmsted. These include Central Park, in which the Metropolitan Museum itself is located, Morningside Park, Prospect Park in Brooklyn, several more sites in New York State, and others in Arkansas, Kentucky, Wisconsin, and Massachusetts. This body of work, produced in the 1990s, relates as well to Mr. Friedlander’s series of photographs shot in apple orchards and in the scrub of the Western deserts.

Mr. Friedlander is one of our most prolific and protean photographers, an artist of great sophistication, whose “ramble” is as concerned with the nature of photography as it is with appreciating the trees Olmstead set out for him and for other park-goers. Since the parks themselves are works of art, there is a complex interplay of artifact and nature involved in shooting these trees. And he does not have the resources that were available to the photographers represented in the Metropolitan’s exhibition last year of mid-19th century British photography; they drew on the attenuated medieval notion of a chain of being, in which there is a hierarchy of trees in order of their nobility, and in which each species is emblematic of some abstract concept. The meaning and expressiveness Mr. Friedlander seeks to impose is not derived from cultural significance, but from the visual possibilities presented to him by the actual trees.

The exhibition concludes with “Lake Park, Milwaukee, Wisconsin” (1992), an exquisite picture of a tree growing from a crack in an outcropping of rock. The tree is backlit and therefore first seen as a silhouette, but Mr. Friedlander set his exposure so that on closer inspection the texture of the tree’s bark and of the rock are clearly visible. The tree does not rise straight up but tilts slightly to the left, and there is an appealing, balletic arc to the trunk as it holds up the filigree of its leaves and branches. The solid mass of the rock at the bottom of the picture is dramatically contrasted with the delicate tracery of the organic matter it supports. The formal perfection of “Lake Park” is like the tonic chord that ends a musical composition by resolving all its prior dissonance.

I start at the end because Jeff Rosenheim, who curated the show, set many more problematic works before it. The park lamp in “Prospect Park, Brooklyn, New York” (1989) has had its glass globe broken and, worse, the ground alongside the path has heaved up to set the pole at an angle; nature, too, is a vandal. In “Shawnee Park, Louisville, Kentucky” (1990), all we see of an apparently stout tree is its shadow splayed on a hillside; we have to imagine the tree. (This is like the famous street photograph in which the shadow of Mr. Friedlander’s head is cast onto the blond hair of the woman he is photographing.) In “Morningside Park, New York City” (1992), Mr. Friedlander plays havoc with a mélange of leaves by putting his lens so close to some in the lower left corner that our sense of perspective is thrown off.

More difficult yet is “Central Park, New York City” (1993) in which one of the park’s ornate bridges is barely seen through a scrim of reeds and branches. When I complained to Mr. Rosenheim that I didn’t understand the principle that was supposed to organize the chaotic growth in the foreground of the picture, he hauled me off through the Met and sat me down on a bench in front of Jackson Pollock’s massive “Autumn Rhythm (Number 30)” (1950). This was a skillful gambit, but Pollock’s paint drippings, though hasty, were controlled and rhythmic; nature’s patterns are controlled genetically, but may appear disordered. Still, it was easier to appreciate the Friedlander after the Pollock.

Mr. Friedlander’s intentions are challenging, and his method in this project, as in most of his career, is analytic. He is like J.S. Bach working his way through the “Goldberg Variations,” or Wallace Stevens setting out to discover “Thirteen Ways of Looking at a Blackbird,” or a jazz musician playing riffs on a tune. If not every picture is fully resolved, it may be because there is meaning in discord, and because a picture gains in expressiveness when the viewer must participate in the effort to locate it. Mr. Friedlander’s companion on his ramble is hardly Kilmer; more likely it is the magnificent W.B. Yeats, who wrote:

O chestnut-tree, great-rooted blossomer,
Are you the leaf, the blossom or the bole?
O body swayed to music, O brightening glance,
How can we know the dancer from the dance?

wmeyers@nysun.com

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