The rolling farmland in the south-eastern end of Pennsylvania is widely regarded as some of the finest pheasant habitat in the land.

But like just about everything else on the East Coast these days, it's planted almost exclusively in corn, and frankly it doesn't look much different from the Maryland countryside 30 miles south.

I was thinking the whole pheasant phenomenon was an overstated myth as I drove up Rte. 15 north of Gettysburg last week. It looked like plain old corn fields to me. I reached for a smoke and pulled into the passing lane to get be a truck.

Wooosh. From the field edge to my left a handsome ringnecked rooster pheasant leaped into the air, flashed its wide wings and flapped across my path 15 yards from the windshield.

It was the first of many ringnecks I'd see that opening day of small game hunting season in the Keystone State. I came home a believer.

I was chatting with John Hoffman, a fish commission official, in his farmhouse in Dillsburg an hour later when a knock came at the door.

pickup "a red-hatted . . . "

A red-hatted hunter peered in. "Mind if we hunt your bramble patch?" he asked.

Hoffman, who has hunted these fields all his life, had no objection. The hunter bobbed off and 15 munutes later we heard shotgun pops from the brush.

There were more shots, then before an hour was up the red hat reappeared to say thanks. "Do any good?" Hoffman asked. "Sure did," said the hat. "Two roosters and two bunnies. Can't complain about that."

Pennsylvania's pheasant season began Oct. 28 and closes for deer seaon Nov. 25. It reopens for two weeks the day after Christmas.

If this season is anything like the last seven or eight, close to 1.2 million pheasants will be harvested by hunters in that time, and the vast majority will be taken in the 18 south-central and southeastern counties that make up the primary pheasant range.

According to Dale Sheffer, the state's chief of game management, that marks a substantial drop from 1970 and 1971, when about 1 1/2 million pheasant were bagged each year.

It is not a decline that has him terribly worried. "Most small animals are subject to fluctuations in population like that," he said.

"We assume it's normal because it's happened in other decades and they've rebounded."

In order to keep the population high, the state pen-raises about 200,000 pheasants a year and sets them free in the fields, some just before opening day and some at intervals during the season.

One of the pleasant factors of pheasant hunting in southeastern Pennsylvania is that folks like Hoffman, who wouldn't dream of refusing respectable-looking hunters access ot his land, seem to be he rule rather than the exception.

This territory still has a good number of small farm holdings, and a lot of these small farmers keep good portions of their fields fallow. The weed fields that result make ideal pheasant habitat.

In addition, there are state game lands in every county. A tour of two near Hoffman's place indicated that they are hunted hard, but not so hard that the game is wiped out after the first week.

He showed me through state land No. 243 off Rte. 15. It's 1058 acres planted in corn and grain with three man-made ponds.

We saw perhaps 50 hunters, many of them with pheasants in their game pouches.

No one knows exactly why pheasants thrive in the lower edge of the Keystone State. "We know that good pheasant land is associated with areas that are planted about 60 percent in small grain," Sheffer said.

"But we've never been able to determine why they don't survive well in areas of Maryland and Virginia that fill that requirement. They can't seem to establish reproducing populations, though they've tried."

Pheasant hunting is a sport best pursued by two or more hunters. The birds favor dense cover and will run great distances before they flush. The idea is to tramp through the brush until a ringnecked male comes up.

Sheffer said pheasants will feed and hide instanding corn fields until the stalks are cut down, and there's a great deal of corn still standing in lower Pennsylvania.

That makes for tough slogging. Hunters often will send two men through the field and post the remainder of the party at the field end in hopes the birds will flush their way.

Later in the year, when the corn is cut, the birds move and weed fields produce the best results.

An out-of-state license for Pennsylvania costs $40.35, and it may be one of the best bargains around for Washington-area shooters willing to travel. There is top pheasant shooting, the best deer hunting in the nation and superb wild turkey populations.