Which sentence accurately describes lyctid infestation characteristics?

Lyctid beetles, often referred to as "powderpost beetles," are known for their tendency to infest certain types of wood, particularly hardwoods that are used in furniture, cabinetry, and flooring. The key characteristic of lyctid infestations is their preference for wood with higher starch content, as they can only develop in wood that has a moisture content above a certain level, typically found in freshly cut lumber or certain untreated hardwoods.

The assertion that they are rarely found in wood floors does not accurately represent the behavior of these pests, as lyctid beetles are indeed commonly encountered in hardwood flooring due to the nature of the wood used in such installations. They can cause significant damage to the structural integrity of hardwood products if left untreated.

While it is true that they commonly infest structural wood, they specifically target untreated wood and do not usually attack wood that has been treated with preservatives. This further clarifies that options indicating their presence primarily in outdoor structures or treated wood do not align with their behavioral patterns. Hence, the correct interpretation is that lyctid beetle infestations frequently occur in untreated hardwood materials found in various indoor settings, including wood floors.