Beetle Guide
Beetles are one of the most diverse and widespread groups of insects, with many species found throughout the UK. While some beetles play a beneficial role in the ecosystem, others can become pests when they invade homes or businesses, causing damage to property and food supplies.
This guide will cover everything you need to know about beetles, the risks they pose, and how to manage infestations.
THE DANGERS
Why we control Beetles
Beetles can become pests when they infest homes, businesses, or stored food supplies.
Certain species, such as carpet beetles and wood-boring beetles, can cause extensive damage to fabrics, furniture, and structural timber. In commercial settings, beetle infestations can also lead to contamination of food products, posing health and safety risks.
Beetles around businesses
In commercial environments, especially in the food production and storage industries, beetles can be a major problem. Infestations in food warehouses, restaurants, or processing facilities can lead to contamination, wasted stock, and potential health violations. Beetle infestations in timber or construction industries can also result in structural damage, halting work and requiring expensive treatments.
Property Manager
Some beetles are known for causing significant property damage:
Wood-boring beetles (such as woodworm) can weaken structural timbers, leading to costly repairs. Carpet beetles feed on natural fibres like wool, silk, and fur, damaging carpets, clothing, and upholstered furniture. Larder beetles can infest stored foods and dry goods, spoiling them for consumption.
Did you know:
The UK is home to over 4,000 species of beetles! This diverse group includes ground beetles, ladybirds, and stag beetles, found in a wide range of habitats.
beetle BIOLOGY
TYPES OF BEETLE IN THE UK
The UK is home to various beetle species, some of which can become serious pests when they infest homes, businesses, or stored products. Below are the most common types of pest beetles in the UK, along with descriptions of their appearance and the damage they can cause.
Common Black Ground Beetle (Carabus nemoralis)
Size: 10-20 mm in length
Shape: Elongated, oval body
Colour: Shiny black with a smooth texture, often with faintly patterned elytra (wing covers).
Damage: While not typically harmful to humans or structures, these beetles can be beneficial as they feed on pests like slugs and caterpillars in gardens. However, in large numbers, they may become a nuisance and occasionally invade homes in search of food.
Carpet Beetles (Anthrenus verbasci)
Size: 2-4 mm in length
Shape: Oval body
Colour: Mottled black, white, and brown; larvae (known as "woolly bears") are brownish and covered in tiny bristles.
Damage: Carpet beetles are notorious for damaging natural fibres like wool, silk, and fur. Their larvae feed on carpets, clothing, upholstery, and other materials made from animal products. You may notice bald patches on carpets or holes in fabrics. They often thrive in areas with little foot traffic, such as under furniture or in loft spaces.
Larder Beetles (Dermestes lardarius)
Size: 7-9 mm in length
Shape: Oval body
Colour: Dark brown to black with a distinctive pale yellow band across the body, marked with dark spots. Larvae are dark brown with spiny bristles.
Damage: Larder beetles are primarily food pests, infesting stored foods such as dried meats, pet food, and cheeses. They can also be found in pantries or cupboards, feeding on high-protein substances. In severe infestations, they can spoil large amounts of stored food.
Flour Beetles (Tribolium castaneum and Tribolium confusum)
Size: 3-4 mm in length
Shape: Long, flat body
Colour: Reddish-brown
Species: The red flour beetle (Tribolium castaneum) and confused flour beetle (Tribolium confusum) are similar in appearance.
Damage: These beetles are common in stored grain and flour products, contaminating food supplies in pantries, shops, and warehouses. Infested products may develop a foul odour or discolouration due to beetle droppings and dead beetles. They can render large amounts of stored goods unfit for consumption.
Deathwatch Beetle (Xestobium rufovillosum)
Size: 5-7 mm in length
Shape: Oval, with a rounded back and flattened head
Colour: Brown with fine patches of yellowish hair on the body.
Damage: Deathwatch beetles are wood-borers and are particularly damaging to old or decayed wood. They often infest timber in historic buildings or older furniture. The larvae bore into wood, leaving holes and frass similar to woodworm, weakening wooden beams and supports over time. The adults make a distinctive tapping or ticking sound, which can often be heard at night.
Grain Weevils (Sitophilus granarius)
Size: 2-4 mm in length
Shape: Elongated body with a pronounced snout
Colour: Dark brown or black
Damage: Grain weevils are a common pest in stored grain, wheat, rice, and corn. They lay eggs inside kernels, where the larvae develop by eating the grain from the inside. A large infestation can ruin products in granaries, food warehouses, and even home pantries.
WHEN ARE BEETLES MOST ACTIVE
Beetle activity tends to increase during warmer months, particularly spring and summer. This is when beetles are most likely to breed, and their larvae develop. Wood-boring beetles, in particular, are more active during the summer, while food storage beetles can be a problem year-round, especially in warm, indoor environments.
SIGNS BEETLES ARE AROUND
Common signs of a beetle infestation include:
- Shed skins or larvae: Many beetles leave behind shed skins or empty shells during their lifecycle.
- Holes in wood or furniture: Tiny holes and fine dust may indicate wood-boring beetles.
- Damaged carpets or fabrics: Holes, worn areas, or disintegrating fabrics could point to carpet beetles.
- Infested food: Small beetles or larvae in dry goods like flour, grains, or cereal boxes.
Did you know:
Stag beetles (Lucanus cervus) are the UK’s largest beetle species, with males sporting large, antler-like jaws. These beetles can grow up to 7.5 cm long and are mainly found in southern England.
MANAGING BEETLES
PREVENTING BEETLES
To prevent beetle infestations, it’s important to:
Store food properly: Keep dry goods in airtight containers to prevent access for stored product beetles.
Inspect second-hand furniture: When buying second-hand items, check for signs of wood-boring beetles or carpet beetle damage.
Seal cracks and crevices: Prevent wood-boring beetles by sealing entry points and treating timber with protective coatings.
WASTE MANAGEMENT
Small infestations can often be managed with DIY solutions like insecticide sprays or traps, but larger infestations, especially of wood-boring or carpet beetles, may require professional treatment.
In severe cases, fumigation or heat treatment may be necessary to eradicate beetles from homes or commercial properties.
ARE BEETLES PROTECTED?
Most beetle species in the UK are not protected and can be controlled when they become pests. However, beetles play an important role in ecosystems as decomposers, so it's crucial to use ethical methods to manage infestations, focusing on prevention and responsible control measures.
DIY BEETLE CONTROL
DIY beetle control can be effective in minor cases. Regular vacuuming and cleaning can help remove carpet beetle larvae, while woodworm infestations can be treated with specialised sprays. Ensure that food storage areas are regularly cleaned and dried goods are stored in airtight containers.
PROFESSIONAL BEETLE CONTROL
For more serious infestations, professional pest control is recommended. Pest control experts will assess the situation and use the most effective and humane methods to remove beetles from your property. Woodworm infestations, in particular, may require structural treatments, so it’s essential to seek professional help to avoid long-term damage.
