Hee-haw! Scores of farms across the country are opening up to overnight guests. _  Sure, you and your kids plan to conquer the theme parks. In the meanwhile, why not make a little hay? Farm stays are fast becoming the great American alternative to the pre-packaged vacation. LIBERTY HILL FARM Rochester, Vt.; 802/767-3926; www.libertyhillfarm.com. Adults$75, teens $50,kids 12 and under $35, including breakfast and dinner; shared baths. Beth and Bob Kennett run a farm straight out of a storybook. You'll find Beth in the kitchen, rolling out dough  for a pie. Bob's busy with other work. Guests sleep in seven sunny bedrooms right in the farmhouse and can participate in any of the farm jobs. Maybe you and your kids won't be up at 6 a.m. to meet the milk truck, but you can help with the milking twice a day, collect eggs, and pick sweet corn and wild blackberries in season. HULL-O FARM Durham, N.Y.; 518/239-6950; www.hull-o.com; Adults $110, kids 10--14 $60, 5--9 $50, 2--4 $35, under 2 free, including breakfast and dinner; private baths. It started in 1993 as a way to bring in some extra money at a time of falling milk prices. But soon after Frank and Sherry Hull opened their Catskill Mountains dairy farm to overnight visitors, they discovered they loved it. As you drive up, Sherry greets you on the porch of the 1825 farmhouse with a cow-shaped cookie jar. Before long your kids are playing around with the cows, sheep, ducks, goats and getting ready for a hayride . MERAMEC FARM CABINS Bourbon, Mo.; 573/732-4765; http://www.wine-mo.com Doubles with private bath $75, $10 per additional person. Trail and riding fees extra. Climb onto the back of the Ford pickup and catch up with the herd. One gentle cow named Cricket will even let the kids sit on her back. At the barn , Carol will introduce you to the horses ---15 Missouri Fox Trotters --- and lead you on a trail ride over the hills and down along the spring-fed Meramec River, where everyone swims. Grab a fishing pole and head back to the river. When you have your fill of the wild, try Carol and Dave's favorite restaurants or wineries , within 20 miles of the farm. We can learn from the three ads that   _  .
Hull-O Farm was not built for overnight visitors Frank and Sherry Hull run a farm out of a storybook kids can sit on a gentle cow's back on Hull-O Farm you can't milk a cow if you get up late on Liberty Hill Farm