ROYALTON (AP).- For $275, you can bid to adopt a purebred ram from Fat Rooster Farm and help its owners for a day during lambing season. For $1,375, you can bid on helping create habitat for the chestnut-sided warbler and spend a day birdwatching with an expert at Fred Pond. If quaint New England is your thing, how about ponying up $13,750 to help preserve the Howe Covered Bridge, a 19th-century structure in Tunbridge? They’ll put up a plaque with your name on it if you do. This is no ordinary sale: A Vermont conservation group is holding a “landscape auction” this weekend in which private landowners sell working landscape elements from the White River watershed in hopes of raising money, promoting sustainability and giving city folks a dose of country living. The auction is a way of promoting conservation by putting donors in the habitat they’re being asked to help preserve. Conservation advocates call it a welcome new fundraising tack at a time when many donors have curtailed