Beetles make up the largest order in the animal kingdom, so it is best to focus on identifying only the most common species. This fact means that one in four of every animal on earth is a beetle. Identifying beetles can help you determine which ones are a harmless annoyance, and which ones are harming your home or garden.
Asparagus Beetle
This beetle is about a 1/4 inch in length, with a black and blue head and body, red thorax and yellow/red wing covers. The adult beetle is a danger to asparagus. The larvae are harmless, so in order to control infestations, it's important to remove the eggs before the larvae can make a home in your garden and grow to adut size.
Common Click Beetle
Known worldwide, click beetles are usually no larger than 3/4 of an inch long. The are flattened elongated beetles, with a mechanism to produce a loud clicking sound after being turned upside down. The adults are harmless but the larvae are particularly dangerous to vegetation, and in large numbers can destroy a garden. You can control their numbers by reducing the number of lit outside lights at night since the adults are attracted to lights.
Common Pine Shoot Beetle
These beetles are cylindrical and up to 5mm long. Their heads and thorax are black, and they have reddish brown wings. Native to Europe and Asia, they now inhabit six US states. These beetles are most damaging to pine trees, particularly Scotch pine, especially when they feed on the shoots. The best way to manage infestations is to remove dead and dying pine trees, thereby removing breeding sites.
Common Furniture Beetle (House Borer)
This beetle is a woodboring beetle. The adult is roughly a 1/4" in size, with a flattened dark body. Found mostly in the eastern half of the US, the adults are generally harmless, but the larvae can reduce wood to powder. They do not attack live wood, only sapwood timber, which is why they're usually found in buildings and homes. These beetles generally have to be removed with pesticides.
Ladybugs/Ladybirds
The ladybug (ladybird in Europe), star of many a children's book, is probably one of the most recognized beetles due to its small round red shell coated with black dots. The ladybug is generally considered a gardener's friend due to its pest control capabilities.
Black Ground Beetle
This beetle is mostly black with some red/brown markings on its antennae and legs. The worst thing about this beetle is that it tends to seek shelter in your home during the cold winter months. Other than that, this is actually a very helpful beetle to humans. It does not pray on vegetation or wood, and tends to prey on insects that are harmful. Since they are helpful to the ecosystem, it is advised that you don't use pesticides in an attempt to get rid of these beetles. It's recommended that you use a vacuum to suck them up and then release them outside.