(Ugo no takenoko; “Bamboo shoots after the rain”)
The same thing, or similar things, popping up one after another. Repetition. Recurrence. Like a profusion of bamboo shoots sprouting after the rain. Like mushrooms after the rain, in Western parlance.
This simple idiom is a noun phrase. It begins the adverbial noun 雨後 (ugo), “after the rain.” The associative particle の (no) marks it as connected to and modifying the noun 筍 (takenoko), “bamboo shoot.”
Apparently some people interpret this phrase as referring to speedy growth, but this is considered an error.
Takenoko may also be written using better-known characters, as 竹の子.
(“Saikin, oshoku sukyandaru ga ugo no takenoko mitai ni hinpan ni arawareteiru you na ki ga suru.”)
[“I feel like recently, corruption scandals have been cropping up nonstop, like mushrooms after the rain.”]