This time of year the cottonwood trees are sowing their seeds aloft with that white fluffy snow-like fuzz. I have 2 very large cottonwood trees in the lot next to mine and they have been working overtime to spread their spawn throughout the neighborhood. I took my P2V+ out yesterday evening to get some shots of the moon rising over Detroit. near the end of my flight, I flew back to my driveway and hovered approximately 5' high, pushing a whirlwind of cottonwood fuzz. I thought "Wow, this looks cool!" Then my Phantom started losing altitude quickly. Not VRS as I was in ground effect and it was still coming down at near full throttle. I managed to get it on the ground softly and shut it down. The leading edge of the prop blades were layered in nappy cottonwood fuzz and were unable to create enough lift to keep the Phantom airborne even at full throttle.