The speaker describes themselves as a tree wearing a mask, someone who was once admired. People bowed when they first saw it, and the way ahead seemed open. But that good time burned out quickly, like a lit match. When the tree falls, the crowd turns on it and calls it a "pitiful lying blossom," suggesting the speaker was seen as fake, small and weak, pretending to be something grander.
The poem seems to be about losing an image you built for yourself and being judged for it. The speaker admits to once being a blossom, and says that people now think they are "what I tried to overcome," so the mask was perhaps an effort to become stronger, not to deceive. The mood is tired and hurt. The speaker tries to regrow but feels the forest has taken everything left. Ending with the same insult, now spoken by the speaker, suggests they are close to believing it, or are stuck carrying it.