[floatboth]

"introduce HORS with trees (HORST)"

Would be much better if the data structure was not trees but something whose name started with the letter E...

[pbsd]

Although not stated anywhere, the name could be an homage to Horst Feistel, one of the most influential cryptographers of the 20th century.

[glibgil]

HORS with ents, HORSE