[big green bloke]

hi every one just a quick question when can i prune my walnut tree to stop it becoming to tall yours big green bloke  

[Aunt Sally]

I've no idea BGB.  But these people might  

http://www.rhs.org.uk/advice/profiles0805/walnut_pruning.asp

[Annie]

All I know is don`t prune spring/summer when the sap is rising as they tend to ooze badley. and branches can die.

[penance]

Spring or summer is the time, trees dont die from bleeding.
It will stop of its own accord.

[vegging out]

The sap rises very early in walnuts,summer is fine for walnut pruning or once the leaves are fully open,this leaves plenty of the growing season for pruning wounds to callus over lessening the chances of fungal/bacterial deceases entering.Make sure you don't cut branches flush to the stem as this will/can cause serious problems.
  This may be helpful..
 http://www.na.fs.fed.us/Spfo/pubs/howtos/ht_prune/cuts.htm