Trees are going to drop leaves or needles or berries or nuts from time to time, and they’re going to cast shade depending on where the sun is. The general legal principle is that neighbors can’t sue the tree owner just because these natural events happen.
Reasoning: It’s useful here to ask what would happen if neighbors could sue for leaves, needles, berries, or nuts falling into their yard. We might predict that there would be a lot of extra lawsuits where the neighbor would win only a tiny sum of money – probably the amount it would take to hire someone to clean up his/her yard. Also, neighbors who sued for fallen leaves (berries, etc.) in their yard would be able to sue the tree owner every year when the leaves (berries, etc.) fell again. Anyone who owned a tree might find himself being perpetually sued by all of his neighbors over the natural consequences of the seasons.
The only way a homeowner could thoroughly protect himself from constant lawsuits would be to cut down all of his/her trees. But as a matter of public policy, Americans generally like trees around their homes. They increase the natural beauty of an area, are good for the environment, and provide shade that lowers a homeowner’s utility bills. If the law balances the social cost of leaf litter against the social cost of discouraging trees, it will probably decide that the leaf litter is the lesser evil.
There is also a legal maxim sometimes expressed in Latin as “De minimis non curat lex.” In English, this means “The law doesn’t care about trifles.” Fallen leaves in the autumn, or berries in the summer, generally count as trifles.
Example: If a pinecone from Jane’s tree falls in John’s yard, John doesn’t get to sue Jane for trespass. If Jane’s pine tree casts shadow on John’s garden so his tomatoes don’t grow, John is probably just out of luck. He can’t sue Jane for the tomato crop he thinks he would have gotten if not for her tree.
Eddie owns a huge mulberry tree with branches that extend over his neighbor Fanny’s yard. Every summer, mulberries from Eddie’s tree fall onto Fanny’s grass. Fanny is a very neat person who doesn’t like mulberries on her grass. She asks Eddie to clean up the messy mulberries, and also to cut off his mulberry tree branches where they overhang her yard. He refuses. Fanny sues Eddie to get the court to force him to clean up her yard and cut off the offending tree branches. Which person is the court more likely to decide for —
Eddie is the probable winner here. (But see subsection 5 below for what may happen if Fanny takes matters into her own hands.