Sylvan Cherubsprout

The monster effect "When this card is Special Summoned: You can excavate up to 2 cards from the top of your Deck. If there is a Plant-Type monster among the excavated cards, send all those monsters to the Graveyard. Place the remaining cards on the bottom of the Deck in any order" is a Trigger Effect. (This effect does not target. You choose to excavate either 1 or 2 cards from the top of your Deck when resolving the effect.)

The monster effect "You can excavate up to 2 cards from the top of your Deck" is an optional effect that can be activated when "Sylvan Sprout" itself is successfully Special Summoned in face-up position. (It can also be activated during the Damage Step.)

The process of "If there is a Plant-Type monster among the excavated cards, send all those monsters to the Graveyard" and the process of "Place the remaining cards on the bottom of the Deck in any order" are treated as occurring simultaneously.

The monster effect "If this card is excavated from the Deck and sent to the Graveyard by a card effect: You can Special Summon 1 Level 1 Plant-Type monster from your Deck" is a Trigger Effect that activates in the Graveyard. (This effect does not target. It can also be activated during the Damage Step.)