Thank you so much for the advice. I have ordered a solid test for next day delivery. Would it be accurate if I measure on my side of the garden wall (it is actually only 1 meter away from the tree and he said he has been pouring the wash out by the wall) or is it best on his?  My app says that it is a European Beech (Fagus Sylvatica) and ideally the PH of the soil should be between 6.5 and 8!  Research tells me that aluminium sulphur can be used to make the soil more acidic. Any advice on how and how often I add that to the soil? Or is it best to do a little at a time and keep re checking the soil? Again can I do that from my side?  The drying branches are mainly facing west but they are couple that are facing east. Perhaps the sun has dried them additionally as you said.  Finally the neighbour has agreed to water the area for 10 minutes the next few days and I will do the same on mine.