The arbol tronador is, perhaps, one of my new favorite trees. The direct translation of that is 'thunder tree.' The botanical name is Hura crepitans.
I don't have a photo of the tree itself, but if you click on the link you can find some photos of it. What I do have are photos of the incredibly cool seed pods.
This plant is called thunder tree in Spanish because when the seed pod dries out enough and the seeds themselves are ready to be dispersed into the Central American forests, the pod literally explodes, sending the seeds flying. The noise it makes is loud enough that thunder tree is a fairly accurate description.
I was dubious when I was introduced to this fully intact seed pod. (Naturally, I was in Central America at the time, as bringing plants into the US is a no-no.) Dubious, but extremely hopeful that the plant would live up to its common name. I carried the seed pod with me everywhere. And then, one day while I was deep in concentration reading something, the thing went off. It made a popping noise that was so loud I yelped (okay it was more of a shriek). A seed hit my hand with surprising force. Not enough to leave a red mark or anything, but there was a shocking amount of impact.
Seeds and seed casings were everywhere. The biggest distance a seed traveled was 17' away from the seed pod, with a suspected arc of about 7' high. Absolutely amazing.
Here's a shot of the seed and the stem of the seed pod -- the pumpkin looking pod exploded into dozens of pieces, but the stem barely left its original spot.
Below are some shots of the frisbee-like discs that made the chambers for individual seeds. It's yet another amazing example of incredible plant structure.
The English common name is much less evocative than arbol tronador. It's called sandbox tree instead. This apellation is due to the fact that immature fruits were often hollowed out and filled with sand for blotting ink.
We were careful with all these seeds, as Hura crepitans is highly poisonous. If ingested, the seeds can cause 'severe gastric distress' or even death. The oils from the seeds can temporarily or even permanently blind someone.