Who is responsible when a tree or limb falls on a neighbor's property, causing damage or personal injury? These issues are raised in two letters to the Mailbag.

Larry N. Thompson of Silver Spring recently put new fencing around his 60 acres. Due to gypsy moth infestation several years ago, many dead trees are on both sides of the fence. Two dead trees on neighbors' property fell and tore down a portion of Thompson's new fencing. Repairs cost about $1,900. Both neighbors said their insurance would not cover the damage and refused to pay.

Thompson asks, "Are my neighbors liable?"

Robert W. O'Reilly of Fallston wants to know who is responsible for removing debris from a healthy tree that fell on adjoining property during a windstorm. O'Reilly asks, "[If] there was no prior recognition or warning that it would fall over, is the person on whose property the tree stood liable for removal of all the debris?"

The legal rights and obligations of the adjoining owners depend on the particular facts. Let's look at each case separately.

In Thompson's case, the neighbors' trees had been dead for several years due to gypsy moth infestation, which was common in the rural area where Thompson has his 60-acre farm.

Courts in a number of states have held that a landowner who knows that a tree on his property is dead or decayed and may fall and damage the property of an adjoining landowner has a duty to eliminate the damage by removing the dead or decayed tree.

The rule is most often applied in urban areas, where a landowner is said to have a duty to exercise reasonable care to prevent harm to adjoining property arising from defective or unsound trees on the premises.

On the other hand, in rural areas, where it is more common for naturally growing trees to decay or die, courts have been reluctant to impose liability when a dead tree falls without warning.

These cases rely on a legal principle that a landowner has no affirmative duty to remedy conditions of a purely natural origin on his land, though they are dangerous to his neighbors.

Maryland's appellate courts have not ruled directly on a case with facts similar to Thompson's. If the trees were obviously dead and the landowner knew that they were likely to fall and damage Thompson's fencing, his claims against his neighbors may have merit.

Thompson's claims probably would fail if he erected fencing adjacent to trees that he knew were dead and dangerous, or if the trees fell during an unusual windstorm.

In O'Reilly's case, a perfectly healthy tree fell without warning on adjoining property during a windstorm. Since the landowner had no reason to expect that his naturally growing tree might fall, and it fell due to an "act of God," the landowner has no liability to his neighbor, either for damage to the neighbor's property or even to remove the tree from the neighbor's land.

O'Reilly's case falls under the legal rule that a landowner is not liable to people outside the land for damages resulting solely from naturally growing trees and other natural conditions of the land.

NEXT WEEK: Readers ask, "What are the rights and obligations of adjoining property owners when trees or limbs encroach across a boundary line?"