David Letterman gives Explod-O-Pop® popcorn to members of The Late Show audience on occasion. That's fun. But not nearly as much fun as I'm having with the seeds I collected from the garden. Most of the seed pods are perfectly harmless. Just open them and scrape out the seeds. But there are some that should come with a warning label:

WARNING: May cause eye injury. It is advisable to wear eye protection while handling these seed pods. It is also not recommended to handle these seed pods if you have a heart condition. They are unstable and may spontaneously explode, causing sudden startling to the handler. Proceed with caution and at your own risk.

• Balsam, also known as Touch-Me-Nots (Impatiens balsamina)
  
  Guess how they got that name? They're pretty cool, actually. Pick a pod, hold the ends between your thumb and index finger and squeeze. Whoa! It's like a little grenade went off in your hand. They're designed this way for a reason, of course. Let your plants go to seed and they'll spread far and wide in your garden - as far as their little launchers will toss them. They're annuals, but don't count on it. Unless you pull the plants or seeds before they start exploding, you'll have them again next year. I promise.
  
  
  
  
  
  
  

• Snow-On-the-Mountain (Euphorbia marginata). It's a beautiful plant and nothing in the name suggests what I'm about to reveal. The seed pods are a tripod, meaning they have three lobes, each one containing a round brown seed. (I just made that tripod thing up. They aren't really called that.)

When you pick the seed pods off the plant and take them into the house, unless you want them all over the house, you must put a piece of paper or paper towel over them as they dry. Last fall, when I gathered these pods for the first time, I laid them out on a plate and went to bed. They were brown already, but I wanted to make sure they were good and dry before putting them in their bag for storage.

When I woke up the next morning, there were seeds all over the kitchen! I blamed the cats. They just stared at me as if to say, "I have no idea what you're talking about." Yeah, that's what they always want me to believe. It turns out they really didn't have a clue and neither did I.

I stood there, pondering the possibilities of how those seeds managed to get from here to there and then it happened, right before my eyes. SNAP! Oh, there goes another one. CRACKLE! Hey, that one hit me in the cheek! POP! Run for cover!

As the pods dry, they shrink. When they shrink, they crack open and propel the seed AND the pod parts all over the place. These are annuals too, but don't try to tell them that. They're perennial wannabes and I've had them come up a good 20 feet away from where they were the year before.
 

There are other plants that also throw their seeds, but that's not the only way seeds get from one place to another for propagation by self-seeding. Some act as parachutes (milkweed and dandelions), others as helicopters (maple seeds). There are hitchhikers of two sorts: some are sticky on the outside and grab onto things (Chinese Forget-me-nots) and others travel inside birds after they eat them and they get 'deposited' elsewhere (several kinds of berried fruit).

Fascinating stuff, these seeds.