ST. CROIX’S ‘DYNAMITE’ FRUIT: MEET THE TOXIC, EXPLODING SANDBOX TREE
SOMETHING WILD: A member of a local social media gardening group shared these images of a fruit found on St. Croix, sparking an urgent identification effort. The "innocent" pumpkin-like pod is actually the fruit of the Sandbox Tree (Hura crepitans), a toxic species famous for its exploding seed pods. (Photo: Courtesy of Shalym Lugo / St. Croix Plant Identification and Gardening Support)
By JOHN McCARTHY / St. Croix Sun Staff Writer
THE RAINFOREST — If you’ve been hiking the Northside or exploring the bush and spotted a small, green, pumpkin-like fruit on the ground, you might think you’ve found a unique island "gem".
Think again.
What you’ve actually found is the fruit of the Sandbox Tree (Hura crepitans), also known locally as the "Dynamite Tree." And it is one of the most "shiesty," toxic, and downright dangerous plants in the Caribbean.
The "Something Wild" Nature of the Sandbox Tree
The Sandbox tree doesn't just grow; it prepares for battle. Everything about this tree is designed for defense and aggressive seed dispersal.
The Spiky Armor: The tree’s trunk is not smooth. It is covered in formidable, conical spikes that make it nearly impossible to climb and dangerous to lean against.
The Exploding Fruit: The innocent-looking fruit seen in a recent St. Croix Plant Identification group is a botanical bomb. When the fruit dries out, it doesn't just fall—it explodes with a sharp crack that sounds exactly like a pistol shot.
160 MPH Seeds: This "poppy show" isn't just for show. The explosion launches the sharp, flat seeds at an incredible speed of 160 mph (70 meters per second), sending them up to 100 feet (30 meters) away. It is the ultimate social distancing plant.
A Toxic Threat: If the spikes and explosions weren't enough, the entire tree is "shiesty" with a milky, caustic sap that is highly toxic to humans and animals. Historically, the sap was used by indigenous peoples to create poison-tipped arrows. Ingestion of the seeds is known to cause severe, violent vomiting and diarrhea.
The "Sandbox" Name
So why is such a deadly tree called something as playful as a "Sandbox"?
According to botanical history, the name comes from a time before blotting paper and ballpoint pens. When the pods were carefully gathered before they exploded, they could be dried and used as containers to hold fine sand. This sand was then used to dry the ink on handwritten letters.
Today, the Sandbox tree remains a fascinating—if alarming—part of the St. Croix ecosystem. While it makes for a great story, the official advisory is clear: Look, but do not touch.
