Preventing Bow Bugs and Cleaning Your Violin Case | Useful Tips | Callier-Scollard Violin Shop

If you have opened your case after not playing for a while and the hairs are breaking it might be the work of the "Carpet Beetle Larvae". They like to eat horsehair when it's in a dark case. They tend to eat in one place straight across the hair, but I have seen violin cases that haven't been opened in decades and there isn't any hair that's longer than one inch.

If you look closely at the spot where the hair has broken most likely you will notice a slight divot out of the hair. Also, I think they must like the taste of rosin.

How to prevent bow bugs. If you are playing every day they don't seem to have time to eat the hair, so play daily. Keep unused bows out of a dark place and have them stored in a sealed plastic bow bag. If you don't have a bow bag, then wrapping the bow with cellophane plastic wrap should help protect the hair.

To clean your case I recommend using the following steps.

1. Completely empty your case.
2. Brush out the case with a good brush getting into all the little crevices.
3. Vacuum out the case
4. Spray lightly with a flying insect spray and then close the case and place it inside a large sealed trash bag. Allow it to fumigate for at least several hours.
   • A flying insect spray puts out an Aerosol spray without leaving any residue, it is not a liquid stream.
   • You only mist the inside of the case a little bit. Do not make the case wet.
   • If you are unsure about what type of spray to use or how to spray the case, then just skip this step #4.
5. The next day leave the case "without the bag" open in the sun for a little while so that it warms up a little. Note: don't let your case get too hot.

Varied Carpet Beetle Larva	Furniture Carpet Beetle Larva
Anthrenus species variant (transitional pattern)	Black Carpet Beetle Larva

Common Types of Carpet Beetles That Damage Bow Hair

Carpet beetles are small but highly destructive pests, especially to natural materials like horsehair, wool, and felt linings. While adult beetles are often harmless, the larvae are responsible for most of the damage found in bow cases and string instrument storage.

Below are the most common species encountered in violin and bow shops:

1. Varied Carpet Beetle (Anthrenus verbasci)

   • Larva Appearance: Short, oval-shaped, and covered in dark reddish-brown bristles. Often has light and dark horizontal banding.
   • Adult Beetle: Tiny (2–3 mm), dome-shaped, with a mottled pattern of white, brown, and yellow scales.
   • Behavior: Hides in undisturbed places like violin cases, wool padding, or bow holders. Larvae feed on keratin-rich materials, including bow hair.
   • Signs of Infestation: Broken or loose bow hair; papery reddish skins left in the case corners or fabric folds.

2. Furniture Carpet Beetle (Anthrenus flavipes)

   • Larva Appearance: Similar in shape to A. verbasci, but with a more uniform golden or reddish-brown color.
   • Adult Beetle: Slightly larger, with yellowish scales on a darker background.
   • Behavior: Prefers enclosed areas like old furniture, insulation, or case linings. Known to chew through fabrics, horsehair, and leather.
   • Signs of Infestation: Smooth broken hairs and reddish casing skins. Sometimes mistaken for dirt until examined closely.

3. Black Carpet Beetle (Attagenus unicolor)

   • Larva Appearance:Elongated and carrot-shaped, with a distinct tail of bristles. Reddish to dark brown, can grow up to 8 mm.
   • Adult Beetle: Sleek and black or dark brown, about 3–5 mm long.
   • Behavior: One of the most damaging species — can survive long periods without food and often burrow deeply into padding or bow cases.
   • Signs of Infestation: Long, fuzzy larval skins and severe hair breakage. May leave dust-like debris from shredded organic material.

Why This Matters in Bow and Instrument Care

All three species target keratin (the protein in horsehair), and their larvae thrive in dark, enclosed spaces like instrument cases — especially when left unused for long periods. Detecting and cleaning out even the shed skins (called exuviae) is important, as these indicate active or past infestations.

Tip:

If you find small, reddish-brown shells in your case — especially around the frog, tip, or bow ribbon — you're likely dealing with larval molts. This is your warning to act immediately.