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Cockroach Smear Marks: How to Identify?

Sometimes the only sign of cockroach infestation is finding their poop. The roach poop is not easily visible to the eyes unless there is a heavy infestation. The poop is extremely disgusting with a musty odour. Not only does it spreads diseases like enteric fever, but it also triggers allergies, including asthma.

Cockroach smear marks are the black or reddish-brown streaks of liquified roach poop. Due to heavy humidity and dampness, the roach poop turns into a liquid with greasy consistency that leaves marks on the surfaces. Therefore, a surface with multiple cockroach smear marks points towards heavy roach infestation and an underlying roach colony.

An image showing a Cockroach Smear Marks
An image showing a Cockroach Smear Marks
An image showing Cockroach Smear Marks and Cockroach Poop
An image showing Cockroach Smear Marks and Cockroach Poop

Cockroach smear marks can be easily confused with food stains or rust. But, unfortunately, it is probably the worst thing to encounter. Not only does it leave stains on the surfaces, but the smell also attracts a colony of roaches towards itself.

But before you start a grand operation against roaches, first know if the stains are cockroach smear marks or not. I will try to explain each and everything about smear marks in the blog below.

Before you read further, just a quick question. Tired of cockroaches and looking for a permanent solution?

Stop wasting your time, invest in these products and follow this guide: How to get rid of roaches? You will be roach-free in 10-20 days.

1. Max Force Glue Traps
2. Advion Gel Baits
3. Harris Powder Bait
4. Gentrol Insect Growth Regulator
5. Loctite Foam Sealent


Optional Items
1. Gel Bait Professional Gun
2. Torch
3. Powder Bait Puffer
4. Insecticide Spray to kill a reveled colony in a single shot

What are Cockroach Smear Marks, and How it looks like?

Roaches, including palmetto bugs, feed on filth and garbage. They live most of their life hiding in shady, dark, and humid environments. The humidity of the environment has a profound effect on the state of cockroach poop.

In a humid environment, cockroaches usually excrete liquified poop. When viewed from above, the liquified roach poop looks like brown or black curly stains or streaks on the surface. These curly stains or markings are called cockroach smear marks.

The smear marks are usually present where cockroaches nest, usually in damp basements and wet kitchens. However, the smear marks can be found on your bedsheets, curtains and even utensils.

One thing is for sure that seeing cockroach smear marks indicate a heavy roach infestation. The roaches are happily thriving, breeding, hiding and freely pooping around the house. It is time to take action or else things will soon get out of control.

An image showing roach poop marks under sink in kitchen
An image showing roach poop marks under sink in kitchen

Cockroach Smear Marks Can be Dangerous

The cockroach poop carries some dangerous bacterias, including Enterobacteriaceae, Staphylococcus and Mycobacterium species (Source).

These bacterias can cause some dangerous diseases, including Typhoid and Paratyphoid disease.

Therefore, signs of cockroach smear marks or simply liquified roach poop should not be taken lightly.

Katsaridaphobia, An Extreme Fear of Roaches! can be disturbing for some individuals. Read the article to keep yourself aware.

Roach smear mark on a cupboard hinge
Roach smear mark on a cupboard hinge

Cockroach Smear Marks Attracts Other Roaches

Cockroaches, like other insects, communicate with one another through pheromones. Pheromones are chemicals secreted by insects that attract other family members towards themselves.

Cockroach smear marks have a foul musty stench. The smell from smear marks contain pheromones capable of attracting other roaches towards themselves.

Therefore, cleaning smear marks is crucial, or otherwise, a plethora of roaches will start appearing inside your living space.

Do you know that you can repel roaches using Natural Palmetto Bug Repellents? These natural repellent uses the same principle as discussed above to keep roaches at bay.

Cleaning the Roach Smear Marks

Cleaning the roach smear marks is not difficult but rather a disgusting job. Use a mask and gloves before embarking on the procedure.

To clean the roach smear marks,

Step 1: Use insecticide spray, roach baits or traps to kill the roaches.

Step 2: Identify the Surface with Roach Smear Markings.

Step 3: Use hot water and soap to flush the surface or wall.

Step 4: Scrub the surface with a brush or cloth.

Step 5: Leave the surface for 30 minutes and wash again with hot water.

Step 6: Once the surface is dry, use a disinfectant spray to kill the germs.

If the surface is sensitive to water, I recommend using a steam gun instead.

Smear marks on fabrics need nothing special. Just wash it with washing powder in a washing machine. The washing powder contains the necessary ingredients and disinfectants.