As a side note, falling leaves is one of the most dreaded problem in rail transportation. Not only does it obstruct things very efficiently, including the passa

As a side note, falling leaves is one of the most dreaded problem in rail transportation. Not only does it obstruct things very efficiently, including the passage of light, but it also makes the rail surface very slippery, making it sometimes impossible for trains to actually brake using mechanical means. Much much worse than snow or rain. One sympathizes.