Perri,
We sit the woods alot. Actually, you can blend the both of them, field and woods sitting. What I've read and heard over the years, as well as watching predator video's, is that you can't readily call coyotes across open area's very easily. This was based primarily on western coyotes, but I believe it still has some merit up here in the NE.
It isn't a definite, as I've called them out into open fields from woodlines before. But I believe, as a general rule, it is true. Along the same lines, I've read/heard many professional hunter's claim that they had never called coyotes in during moderate to heavy rains.
Windy days is a distant second.
A coyote is more apt to come within range of you if you're following their rules, meaning, leaving a brush line, or woodline for them to gain access to your location, and also, if your scent line is in such a direction that they can't readily cross it.
I mostly sit the woods, but I'm within shooting distance of an open field, and I make sure (as long as the wind cooperates and doesn't change) that my scent travels towards an open area that I believe a coyote wouldn't cross to access that scent.
If they do go so far as to try and get directly below my scent line, it would go against their reclusive nature and they'd have to get out into the open to do so, affording me a very clear shot.
Sitting in the woods, mainly, allows them to get in to me, but because of my strategic location, not get my scent unless they "tip their hand" so to speak.
Sometimes the wind changes and screws things all up, but not usually.
Sitting on the edge of brushy, or corn stalk fields, seems like a middle ground for them, and they'll come out into the open more readily than a bare plowed, or cut afalfa field.
During very foggy days, I've had them come out into the open and stay there, walking around all over. One reason why Dennis was able to shoot the one he did last year. I called for several minutes, then quit, and within 20 mins. or so, he just appeared.
I think they realize full well when they are concealed, and they're very concious of it. At first, I thought it was just instinct, but over the last couple of years I've realized that it is a learned & concious effort on their part.
They don't deviate from it much at all, except for times during mating.
Right about now, until late Feb. or early March. They're monogomous animals, at least on a per season basis, and once they pair up with another, they stay that way, unless one of them is killed. So, once a coyote is hooked up, if you see them at all, they'll usually be together or closeby.
Once the female has the pups, the male will hunt for her, and stay around her den site. She won't let him in to the den after the pups are born, but after they've grown a bit, things change and he's more acceptible by the female around them.
Fox are very similar in the way they react to each other.
Back to "deep woods" hunting......
When we hunt the hardwoods with no surrounding fields nearby, we're more apt to watch that downwind side for the majority of it all. I pick naturally clear area's in the woods so that I can get off a decent shot, as well as afford myself the ability to see them sneaking in. Real thick woods tip the scales towards the coyote's side, and allow him not only to get closer to you without seeing him, but also it allows him to confirm the scent of the suspected quarry.
Their movement in such a case, is far less restrictive, and they are usually in and gone before you realize it.
By positioning yourself in such a way that restricts his freedom of movement through the use of terrain and wind conditions, but not to the extent that it discourages him greatly, in my opinion, is the way to go.
In plain language, for the most part, they'll work to get to you, but not to the extent where they get overly nervous about their safety.
The exception I guess, would be the "half starved" dog that really doesn't care. I guess a great hunger would make them take more chances that way.
Take care & good luck,
Bob