1 of these cards is super-awesome, 1 is good, 2 are "meh" and 1 is baaaaad. I'll give you a minute to guess which is which.
*insert Jeopardy theme*
If you guessed Noxious Field is super-awesome, Sunken Field is good, Flowering and Verdant Field are "meh", and Barbed Field is bad, go get yourself a cookie! You earned it with all that hard thinkin' you just did.
Yeah, it's Geistflame on a stick, and no matter what anyone tells me, they will never convince me that Geistflame is better than Lightning Bolt. If it didn't cost 4 to put on a land, it'd be a bit better (like an Arcane Teachings, but for land) but as it stands it's too expensive.
Pros: Geistflame on a stick
Cons: Geistflame on a stick, really expensive
It's protection against Geistflame! There are very few situations where the prevention of 1 damage is going to save something (unless they use a weak spell like Geistflame (okay, I'm going to stop ragging on that card now)), but it's cheap and there could be a situation that 1 damage could save a creature, so it does fare batter than Barbed Field.
Pros: Weaker Ivory Charm on a stick, cheap
Cons: Only prevents 1 damage
Easily the best out of the bunch. Who doesn't love Pestilence on a stick that doesn't have a sack trigger? Although, it can only be used once a turn, whereas Pestilence can be used multiple times a turn. Still, this is 1 mana cheaper than Pestilence, so it gains a little something there.
Pros: Pestilence without the sack trigger, cheaper than Pestilence
Cons: Can only be used once a turn
Now, I'm tempted to give this card a 6/5 rating because Wizards thinks that Force Spike is ridiculously overpowered and scares away new players (no, seriously, read it in this article). However, as a blue player, I can say with certainty that the 1 extra mana is usually not enough to stop someone in casual. It'll annoy them, but it probably won't stop them outright. However, you could get this out fairly early since it's cheap and you might be able to stop one or two spells.
Pros: Force Spike on a stick, cheap
Cons: Force Spike usually doesn't do anything in casual
Eh, this could work sometimes. It's very much like Flowering Field; there are only a few times where 1 power or 1 toughness is going to make a difference (unless someone's using a certain card, which I promised not to name anymore), but that one time where it comes in handy, you'll be glad you had it. However, unlike Flowering Field, this card isn't that cheap, so it's usefulness is downgraded slightly.
Pros: Weaker Feral Instinct on a stick
Cons: Only gives +1/+1, not that cheap