A tree may be on your land including your back garden, and you may think that it is your property, therefore you can do with it whatever you wish. However, if that tree is subject to a Tree Preservation Order (TPO), this limits what you can do, because the tree has been protected by the local planning authority (LPA). You are legally prevented from cutting down the tree, topping it, lopping it, uprooting it, damaging, or destroying it without permission. You may not be aware that the tree is protected but that does not reduce your liability which is strict.
The LPA is under a duty to inform those concerned that a TPO has been made as soon as it is practicable by serving them with a copy of the TPO, and a Regulation 5 notice stating the reason for making the order. Those affected can make objections and representations, usually within 28 days of receiving the notice. This seems a very straight forward process, sufficient to prevent liability.
However, the nature of property is that it changes hands, and a purchaser may find himself in a position of falling in love with a property but finding out that the seller or even someone who owned the property previously has cut a tree in the garden, and it was subject to a TPO. Regardless of how much you may like a property, you do not want to take the risk of enforcement action for something you did not do. Property owners remain responsible for trees covered by a TPO and must ask the LPA for permission to work on such trees, except, for instance, if the tree represents an urgent security risk, if it is dead, or it is directly in the way of development under a planning permission.
If you find yourself under such circumstances, you might have to show the LPA that you did not breach the TPO should they threaten enforcement action. You may also have to reassure a future buyer that he will not be liable for the breach. It is unlikely that the criminal liability for cutting down the tree passes to you as the new owner, but the liability to replace the tree with one of the same type does. The LPA could serve you, as the owner of the property with an enforcement notice, asking you to do so.
In conclusion, it becomes essential when you are buying a property to find out if there are any trees subject to a TPO, and to ascertain if the order has been complied with. If not, you may have to resolve an issue caused by a previous owner.