Purslane, an annual weed in South Dakota, grows in cultivated areas. It’s known for its drought resistance and grow best in hot weather, storing water in its succulent stems. Seeds from tiny flowers where leaves meet the stem, insure more purslane for next year. This plant is 28 inches across, can stay days uprooted without withering, and can then re-establish itself and grow. Can you top this?
Plant Exchange Blog 
I fight it constantly. I wouldn’t even want to top that! What is the best way to eliminate it? I spray it, but it often takes 2 times to kill it. Mostly I pull, pull, pull.
this proves weeds help hold moisture