what would you do with this neighbor? advice please (Arborist needed)

[John@Outfront]

The stuff running down the wall could easily be sap dripped from a branch that is above that spot....if there is a branch above that spot.

not sap. no branch above, to me it looks like the stain they used for the fence  i have a friend that can do soil samples for me cheap but the time it happened (probably 6 months ago) means lots of the VOC's have escaped

 

[zilla68]

cut the tree, his way, let it fall on his Crap, then walk away lol.

 

[FIREMAN]

Leave the tree up as long as you can make them look at what they did contact the home owner and express your feelings and let him know you will pursue further actions against the home owner if he does not remove the renters. 

 

[Snappy]

Send them some of these....

Ship Your Friends an Embarrassing Box Prank: BigAssDildos. – Witty Yeti

Also... Flowers and cards to him from a " Special Friend" generally get his wife pissed off. Little things like this will get his attention.. Ask me how I know!!! lol

 

[NIKAL]

John, 

First I would get a police report started. Then I’d reach out to the owner/father telling him what you suspect happen. Let him know that at this time you have no intention on removing the tree as your hoping it will heal itself, and you now have cameras on the property facing the tree in case of more retaliation. Let him know that “IF” the tree was to now fall on his house that he could be libel as you have on record him requesting the tree removed, and after denying his request you found the tree poisoned, and this is all documented with a police report of the vandalism. 
 

Also tell him at the time “If” or when the tree will have to be removed you will be expecting him to cover the costs, or possibly face legal recourse to cover your costs and damages. 
 

This might get his attention or he my not care!  Either way he will know you know and that while your being respectful about it your not going to get pushed around.