When we returned from vacation last week, we found a plant that had grown roughly three feet in a week and a half (pic attached). Does anyone have a clue what this beast is? There are no flowers, fruit, or thorns as of yet, and no others in the yard like it. The leaves are linear, and about 3-4" long. We've been surprised by flowers and ground cover that were planted by previous home owners, and wondered if this were another surprise (lily?), or if we should dig it out before the giant climbs down or it creates seedlings.

Does anyone have a clue what it is? Thanks in advance!

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