It's really interesting to me to see this thread because wild turkeys were something of a photographic challenge for me a few weeks ago while they were in their mating season. My Aunt has a country property a few kilometres north of me and has been feeding a flock of wild turkeys for several years. She has also been feeding woodpeckers, cardinals, blue jays, doves, pigeons along with a variety of other birds I can't even think of at the moment.
The turkeys (about 30 of them) feed twice each day on one side of her house....nearest where they can scuttle off into the hills to hide out between feedings. There are a number of feeders on the adjacent side of the house to attract other species and the birds all seem to be used to one another now. At last count there were about 14 'resident' bluejays who dash about her veranda and pick up peanuts off the railing even while she's only sitting a few feet away. The woodpeckers aren't quite as bold but they will come within about ten feet of the veranda while she's on it. All the others do as well even while the turkeys are busy feeding, gobbling or dancing. (And isn't their 'turkey dance' a fascinating thing?)
She was feeding the turkeys grain but now buys cracked corn because it's less expensive and buys various types of feeds to attract other varieties of birds. As a side note, her garden has been specifically planted to attract butterflies and all in all, it's quite a fantastic place to visit!
However, the real point is that there doesn't seem to be any frightening off of the smaller birds because there's so much feed for all of them. A rather time-consuming and perhaps expensive solution but it certainly does make for a beautiful 'nature preserve' and a remarkable photographic resource. It doesn't hurt that she has one of the most beautiful gardens I've ever seen either.