I've been digging in the deep mud with my feet for the past 5 days, lifting chunks of silt and Variable Leaf Milfoil to the surface. Pulling them out from the top, leafy bit just causes them to break off, and stimulates re-growth. No wonder this invasive weed is so successful. Boating and other mechanical disturbance helps it thrive!
I found this tiny 'fragment' on my beach, looking like it had been freshly washed up. I slowly pulled it out, to reveal an established plant, well rooted!
Look at how long the thin white roots can be, spreading down from the coil of viney-looking stem at the top of the next picture:
It's amazing how tall these plants can grow. I placed this dried piece next to my rake for comparison. It begins at the acorn cap in the bottom of the pic, all the way up to the plastic attachment. They can create an impenetrable jungle in deeper water.
I also shudder when I see them dried out afterwards - they remind me of shed snakeskin!