Volunteers have joined the garden

... and threaten to take over.
The taller plant is a sunflower. But there are two three mystery squash plants -- the kin that get 20 to 30 ft. vines in this frame also. They have now blocked off access to the side garden over this wood plank walk. I can only wait and see what they are.
Learning experience: squash seeds planted in the late fall will germinate and sprout earlier than the seeds started indoors. I had assumed that squash seeds would be too tender to stay in the frozen soil over winter. But these winter squash plants have size, flowers, tiny fruits on the long vines whereas the little coddled ones from seed in the house and then transplanted when it seemed warm enough, are still establishing themselves. They just aren't as vigorous as these great mystery vines.
I wonder if they are gourds? I just can't figure out how any squash seeds got in this spot. I may have cleaned out a birdhouse gourd around there. Oh well...Time will tell.