Blue Hunt....White Hunt???

[howaboutthisone]

I have just read on the board at the yard about some local hunts. After the location and time, some of them have the word "blue" in brackets, and others have "white" in brackets. Please could someone enlighten me as to the meaning of blue and white in this respect?

Thanks

 

[Happy Hunter]

Snow or ice??
I think that might be a yard specific thing!