Harming plants, animals, birds, insects or any other living organism is a sin. Do not commit it. All problems (personal and interpersonal) in this world are cascading effect there after which originates from our acceptance or justification to harming.
It is simple to understand how harming results into problems. When I say it is OK harming… automatically I would adopt that in my life. Once it is existent in my life… I am likely to talk rude to someone. Once I talk rude to someone and because he is hurt he will either talk rude back to me or because there is an existing hurt in him he will likely reciprocate it to someone else… if everyone else is OK with hurting then this and this goes on and on and on to reach the situation we are here living with.
On the other hand if no one hurts… there is no question of anyone else getting hurt as well. So, then there is no cascading effect of hurt feeling transmitting ahead. So, removing the habit of harming from our roots itself is important. Only then it will truly stop.