Colourful bacteria film
On September 14, 2007, Reinhard Nitze saw intensely iridescent colours in some puddles on a lane near Barsinghausen/Egestorf (Lower Saxony, Germany). These were probably caused by bacteria of putrefaction coming from decomposing grains of wheat in the water, just as the colours showed up only in those puddles containing larger amounts of grains. The grains originated from the fields along the lane and had probably fallen from a trailer when the harvest was brought in.As some of the grains were already covered with green algae, they must have been lying in the water for some time already. Also remarkable was the rusty colour of those puddles which had already fallen dry.