Mystery Tall Perennial in Maine: Gooseneck Loosestrife or Giant Veronica?

Candidate Species for 8-10 Foot Spikes

Plants this tall with spiky blooms in coastal Maine are likely Lysimachia clethroides (Gooseneck Loosestrife) or Veronicastrum virginicum (Culver's Root).

Lysimachia clethroides (Gooseneck Loosestrife)

Arching white spikes, spreads aggressively. Image reference.

Veronicastrum virginicum (Culver's Root)

Straight, candelabra-like white spikes. Native, clump-forming.

Need for Additional Photos

Close-ups of leaves and flower structure would confirm ID.