Sheffield City Councillors have fallen victim to a collective case of this phenomenon, particularly known to muddy the colours red and green.
Terry Fox was one of the first to be observed displaying symptoms with Roy Munn, Julie Dore and many others following suit.
With the insistence by the council and Amey that the replacement saplings will compensate for the loss of our leaf cover, flood protection and wildlife parallels have been drawn with a triffid attack.
After the brutal removal of numerous cherries, limes and London planes, the suburb formerly known as Greenhill is now called Bluehill.
Going down the hill from Meadowhead Avenue to The Greenway and elsewhere across the city the pavements are now slanting dramatically to the right.
The trees which were once a significant signature of this city, oft cited as the greenest in the country and currently up for the title of The Outdoor City, have gone.
The only solace for those still possessing their sense of colour is that the lettering on the council’s promotional slogan is itself green.
For this we are grateful.