Pihla is the Finnish word for the rowan tree (Sorbus aucuparia) — also called the mountain ash. The rowan is sacred in Finnish-Karelian folklore, the tree of the thunder god Ukko, believed to protect against evil and lightning.
Used widely in modern Finland.
Pihla does not currently appear in the US Social Security Administration's top 1,000 girls' names, so we don't publish a US rank or birth count for it. That says nothing about the name's standing elsewhere in the world — only that it sits outside the ranked US data we rely on.
In Pythagorean numerology the letters of Pihla reduce to 1, The Leader. This is a traditional interpretive system, not a factual claim about the name.