Weights of various lures

Question
Chris, I see that many of the smaller kinds of lures come in weights starting at 1/6 oz and up. What is the determining factor when selecting a lure. I generally use ultra light spinning equipment.
Thanks,
Billy

Answer
First, let me say that I'm incredibly sorry for taking so long to get to this question.  I've been painfully ill, and away from the computer.

Now, to your question.  Lure size is important for several reasons.  The size of a lure is important when matching it to appropriate tackle.  If you attempt to cast a light 1/32 or 1/16oz lure with heavy tackle, it's not going anywhere, and if you try to cast a heavy 1oz lure with ultra light tackle, despite the ability to heave it a mile the tackle doesn't respond well to the size of the lure, and the action and feel of the lure is often seriously flawed.  Also, when using baitcasting tackle, it is vital to adjust the resistance on the reel to correspond with the weight of the lure being cast.  If you don't make it a point to adjust the resistance for each lure you'll inevitably end up with a terrible backlash, or tangled line.

The most important reason, though, has more to do with effectively enticing fish to strike. (why else would you be fishing?)  Smaller lures are significantly more effective than larger ones during cold fronts and other times of general inactivity.  Active periods, such as summer mornings and evenings and fall afternoons typically call for larger lures and faster presentations.  Also, if you're fishing in current, lure weight plays a major role in your ability to catch fish.  As the water level gets lower, you should (typically) use lighter weights to correspond to the change.  This will allow you to better mimick whatever your lure is attempting to and also remain snag free.  

If you have any other questios about this, or if you need a follow up, please feel free to ask and don't be deterred by the amount of time it took me to answer this.  Any further questions I assure you will be answered promptly, as this one would have had it not been for some medical issues.  

Thanks for asking,
Chris