The poem's title, "Issue," works in two ways: something that flows out of a source, and a child, as in "to die without issue." The three short stanzas play on both meanings. A river gives rise to a cold body, which might be a drowned person or simply a chill current. Each flower produces a fruit, which the speaker calls "a perfect stranger," as if even natural offspring arrive as something unknown.
Then the pattern breaks. "From me no one" is the shortest line, and it lands like a door closing. The speaker seems to be reflecting on having no children, or perhaps on leaving nothing behind. The poem doesn't say how this feels, and that restraint is what makes it work. The mood is quiet, cool, and a little stark. There is acceptance in it, but also a faint ache, because the world is so full of things producing other things while the speaker stands outside that cycle.