The initial phrase can be dissected into its constituent parts. “Murderous” functions as an adjective, adding a dramatic or hyperbolic descriptor. “Maple tree” constitutes a compound noun, denoting a specific type of deciduous tree. “Home Depot” is a proper noun, identifying a large home improvement retail company. In this context, the modifying adjective is key to understanding the potential implied meaning.
Attributing malicious intent to a natural object, like a maple tree, is often used figuratively. This descriptive approach can draw attention to potential dangers or problems associated with these trees, ranging from structural issues that might pose a hazard to property or individuals, to invasive root systems causing damage to surrounding infrastructure. The association with a retailer like Home Depot may suggest the source for solutions to these issues.