Amish are like everyone else. There are good and bad. Some of them are real nice folks.
I would say it is illegal unless it is an area designated for horse-riding or it is an area where a motor-vehicle is permitted.
Excerpted this from a link in Woodywooducks post (key in on what I put in bold):
"......the following activities are prohibited:
• Camp or use campsites.
• Contaminate, pollute or degrade groundwaters or surface waters
or any waterways.
• Graze or permit the grazing of domestic livestock; place or
maintain beehives or beekeeping apparatus.
• Solicit or place private advertisements, signs or posters.
• Plant, gather, cut, dig, remove or otherwise injure any plants or
parts thereof, including trees, shrubs, vines, flowering plants and
cultivated crops. (Mushrooms and fruits of berry-producing
plants may be picked.)
• Travel on lands by means of any vehicle or conveyance propelled
by motorized power. (Exemption for individuals with Disabled
Person Permit for battery-powered motorized wheelchair.)
• Ride a non-motorized vehicle, conveyance or animal, except on
roads normally open to public travel, or designated routes as
posted, or while lawfully engaged in hunting, trapping or fishing.
• Ride a non-motorized vehicle, conveyance or animal from the last
Saturday in September until the third Saturday in January, and
prior to one hour after close of lawful shooting hours for spring
turkey season from the second Saturday in April through the last
Saturday in May, inclusive, except on Sundays or while lawfully
engaged in hunting, trapping or fishing.
• Ride a non-motorized vehicle, conveyance or animal on roads open to foot travel only.
• Drive motor vehicles with or without attachments having a
registered gross vehicle weight in excess of 12,000 pounds.
• Use boats propelled by a motor. Battery-powered electric motors
may be used on waterways unless otherwise posted.
• Fish from dam breasts posted against fishing.
• Swim in any dam, pond, lake or stream.
• Injure, destroy or cause damage to property, real, personal or
mixed.
• Remove or attempt to remove any manmade or natural object,
except wildlife and fish lawfully taken. Objects that may not be
removed include animals, rocks, minerals, sand and historical or
archaeological artifacts.
• Participate in, become part of, contribute to or engage in
disorderly conduct.
• Travel on roads open to vehicular travel with vehicle or conveyance
propelled by motorized power that is not licensed or
authorized for operation on a public highway.
• Violate, fail or neglect to follow instructions posted on signs
authorized by the Director.
• Destroy, mutilate or remove any sign or placard.
• Travel by mechanical or motorized conveyance or ride animals on
newly constructed, seeded or planted roads, or other areas, when
posted against travel.
• Consume, possess or transport any alcohol, liquor, beer, malt or
brewed alcoholic beverage.
• Use or possess any controlled substance.
• Occupy, use or construct, place or maintain structures or other
tangible property, except that portable hunting blinds and stands
may be used, provided no damage is caused to trees......"
