Collage is inextricably linked in historic consciousness with poetry, in no small part because of the intimacy of its artistic inventors with poets. Pablo Picasso and Georges Braque, the inventors of the medium, were championed and inspired by poets such as Blaise Cendrars, Pierre Reverdy, and Guillaume Apollinaire, the last of whose verbal experiments invariably entailed play with typography — arrangement of words on the page could be as much a visual as a verbal gambit. Among the Dadaists and Surrealists, there were no union demarcation lines between painter and poet preventing wordsmiths from picking up their scissors: The poets of those supremely literary movements made collages and “found” objects, just as many of the visual artists wrote — in the 1930s, during his close association with Surrealism, Picasso devoted much energy to verse.

Is there something intrinsic to the appeal of collage to writers — to moving bits of paper around in startling, revelatory juxtapositions? The coincidence of two shows of collages by writers of markedly different ilk — a sometime poet laureate and a member of the third estate — raises the question. John Ashbery is the subject of a display of collages, from those made during his undergraduate days at Harvard in the late 1940s, to a series of pieces from 2008 that use Chutes and Ladders boards as their support. Mario Naves, who is perhaps better known as an art critic for the New York Observer, has his fourth solo exhibition at Elizabeth Harris Gallery since 2001.

The coincidence, and the connection with writing, intensifies when you consider both men’s attachment to the postcard. Mr. Ashbery is a consummate collector of postcards, and a receiver and sender of them, too. Many of the collages in this show use a postcard as their foundation: They are framed to allow sight of the recto text — an appropriate strategy for objects as likely to be collected for their literary as much as their artistic interest. With Mr. Ashbery, as we are dealing with images and impulses, the distinction between the two is refreshingly fuzzy. Friendship plays a profound role in his collage activities: The 2008 Chutes and Ladders collages use source materials gifted to him by the late Joe Brainard, and are unquestionably an homage to that poetry-world artist.

Mr. Naves, who in this show returns to a welcome intimacy of scale, calls his collages “Postcards from Florida,” as they date from his brief tenure as a professor of drawing at the Ringling College of Art and Design in Sarasota.

The types of collage Messrs. Ashbery and Naves favor occupy different ends of the spectrum in relation to the key issue with this medium: the legibility and relevance of the source material. In Mr. Ashbery’s images, the sources are virtually pristine. There are figures and objects cut from historic engravings or old magazine advertisements, and then placed in equally intact though incongruous scenes and settings. In “Diffusion of Knowledge” (1972), for instance, a pair of comic strip action heroes flex their muscles on a postcard of the Smithsonian Institution. There is a strange misregistering of the buildings in the background, as the familiar tower seems shadowed by a stenciled doppelganger in bright orange. But there is no confusion about the sources; only the encounter.

In Mr. Naves, by contrast, the imagery is entirely abstract, and the source material, which consists of painted tears of crumpled papers, is fabricated for collage purposes by the artist himself. Where Mr. Ashbery comes from the collage tradition of Max Ernst and Braque, Mr. Naves looks more to Henri Matisse’s late great cutouts, and Jean Arp. The emphasis is on shapes created rather than figures isolated; it is more an aesthetic of unity than incongruity, and is less subversive.

Paradoxically, it could be argued, each writer tends to the opposite extreme in their visual and verbal work. Complicating this idea is the fact that besides his poetry, Mr. Ashbery writes clear, precise, accessible prose commentary on art and literature, but the work for which he is best known and admired is deeply, notoriously difficult. His collages, on the other hand, are formally bright and transparent, tending toward immediately accessible story lines and inherently attractive source materials.

Mr. Naves, by contrast, a journalist whose opinions are as bright and punchy as any editor could wish for, makes jolie-laide abstract art that is rough at the edges, scruffy, almost nonchalant in its casual disregard for any sense of a central organizing principle. The historic collagist he most closely resembles is the German Dadaist Kurt Schwitters (whose example also enthused Mr. Ashbery), in drawing upon detritus whose desuetude survives the alchemy of its artistic transmogrification.

True, Mr. Naves’s “crap” consists of studio stuff, as opposed to bus tickets and candy wrappings from metropolitan streets, and it was originated by the artist for intended transformation. But the result constantly stresses distress and arbitrariness — papers are crumpled as if underfoot; there is never “pure” color but, instead, the contingency of splodges and brushstrokes are always manifest. The initial impression of the scarred, battered surfaces of Mr. Naves’s collages is of a segment of billboard where layers of old posters have been stripped and scraped away — a form already made into art by the Italian pop artist Mimmo Rotella.

So, two highly accomplished visual artists who just happen also to be writers? That seems too easy a conclusion. Mr. Naves — in contrast to public perception of him — is an artist who also writes, whereas with Mr. Ashbery, self and public perception coincide around the fact that he is a poet who makes collages, in the Clausewitzian sense as poetry pursued by other means. Mr. Ashbery’s collages, in contrast to his verse, are eminently likable and legible. Even his coy hints at pederasty are sweetly whimsical. Mr. Naves makes tough, itchy, irksome collages that are strictly for aficionados of abstraction.

It could be said that these are “difficult” writers in very different senses. Mr. Naves is a maverick dissenter as reviled by the art world establishment as Mr. Ashbery is beloved of the poetry world’s. The one is difficult in the sense of being a nuisance, the other in the sense of being brilliantly obscure and impenetrable. Collage presents a means of intensifying his efforts to the one, and of providing gentle relief from them for the other.

Ashbery until October 4 (724 Fifth Ave., between 56th and 57th streets, 212-262-5050)

Naves until October 4 (529 W. 20th St., between 10th and 11th avenues, (212-463-9666)