Roger Swain says he'd rather write about rotten apples and woodchucks than about gene-splitting or nuclear accidents. This science-trained (at Harvard) science editor for Horticulture magazine, where the 21 essays in "Earthy Pleasures" first appeared, grows fruit and vegetables on his New Hampshire farm. He's acquainted with 50 kinds of apple rot. As for woodchucks, sometimes called groundhogs or whistle pigs, he charges after them in him pajamas, bellowing. What stays his hand from violence is admiring the job they do of earthmoving and aerating. These overgrown earthworms, as he refers to them, move 400 pounds of dirt per burrow, tunneling out their passageways. In the tradition of farmyard observer E. B. White and biology-watcher Lewis Thomas ("The Medusa and the Snail") Swain Muses over the familiar, finding in it much that is puzzling and wonderous. "It is not surprising that many wildflowers are rare," he writes. "What is surprising is that they are not extinct." The book is a nice mix of observation, glimpses into current research and snippets of history.

Is he New England born or a convert? Either way, he sounds properly crotchety -- about supermarket tomatoes, or about salt on the streets which ruins sledding, corrodes cars, contaminates water, stains water lines onto shoes. Plumes of spray off the highway drift hundreds of feet, stunting plants and damaging trees.

Swain praises the parsnip, and is entirely convincing. Without giving the formula by which the English made from it a wine resembling malmsey, he passes on counsel, from the National Vegetable Research Station in Warwickshire, to plant it in a hexagonal grid and to let nippings by frost increase the sweetness. Plunging a hand into icy muck to retrieve the prized roots is a springtime rite for the farmer, he says -- an earthly pleasure.

This book can't be counted on as a how-to manual. It's too quirky, flits too quickly (diagrams from the magazine have been replaced with drawings -- attractive ones). Yet it contains a number of tips: how to collect maple sap without overtapping the tree or resorting to "the pill," a chemical sometimes used to increase the flow of sap; how to build a bait hive for attracting wild bees; or how to install homemade lightning rods in oak trees. For cabbage growers overwhelmed by tonnage there's advice on the "gracious art" of fermenting it. Fine tunings for flavor led to sauerkraut "cuttings" similar to winetasting. If the British navy hadn't switched from this dish to limes as a source of Vitamin C, its sailors, Swain likes to think, might have been called krauts instead of limeys.

One essay on cows and cowslips demonstrates that distinguishing plants from animals is not always easy. To fungi, protozoa and blue-green algae, some taxonomists think we may need three more kingdoms than the two -- plant and animal -- we know. There's another chapter I liked on the dependence of some plants on ants. Trillium, for example, distributes its seeds by "travels with an ant."

How did Swain know that your split-leaf philodendron and mine languish on a windowsill, pale, "photo-synthesizing feebly"? In a tropical forest the plant is a "dark, shiny green," and produces 8- to 10-inch cucumber-shaped fruit tasting of pineapple and strawberry. Swain goes on to inform us that philodendron is a skototropic plant, that is, a plant that, as a seedling, grows toward the dark, toward the trunk of a tree, say, only then turning into a sun-seeker. This characteristic was only recently discovered.

A chapter on manure, inspired by the scramble of gardeners to locate a source, touches on the World Champion Buffalo Chip (throwing) Contest in Nebraska and considers how dung beetles tidy the African turf -- flattening a heap of football-size elephants droppings in minutes. Australia, which has, by Swain's count, 6 million cow-dung pads falling on it every half-hour, imported these beetles. The only complaint about their work came from a cattleman who could no longer find cow chips with which to level his irrigation pipes and had to search about for wood.

As someone who ponders the intelligent use of resources, Swain thinks that duckweed, which coats ponds with scum, might better be harvested as a cattle feed if the alternative is using chemicals to get rid of it. He marvels at this tiny, free-floating plant which multiplies so fast that a single square inch of it can cover five acres of water in two months.

It has all been news to me. Now I will think of snow, as Swain does, as the poor man's fertilizer, alive with snow fleas, snow worms, snow algae. Swain finds the first heavy snowfall a sort of liberation for the gardener from tasks undone, an amnesty for procrastinators. I'm glad if it sends him indoors to the typewriter.