Despite all the benefits that trees are able to bring to the landscape, they are also able to cause harm, and as such, sometimes require control or removal, in order for that harm to be abated. Most reported problems arise where trees are growing on or close to boundaries between properties and are accused of causing damage to the property of a third party (although trees owned by the person suffering the damage can also be implicated). This damage actually or perceived to be caused by trees can either be as a consequence of the tree growing normally, or less likely, due to some structural or physiological defect. In cases of the former, leaf fall, fruit drop, honeydew, bird droppings, slippery surfaces caused by shady conditions have all been cited as problems associated with trips, slips and falls, when people are passing under trees. Another cause of tripping can be uneven and deflected surfaces, caused by root growth. This can be a problem when it occurs on public footways and footpaths and is of particular concern for the elderly, infirm and partially sighted.