Rice Weevil: 5 Fun Facts & How to Get Rid of Them

Rice weevils are scientifically known as Sitophilus Oryzae. These are the tiny pest that mostly attacks the rice, wheat, grains and some other crops. We will discuss some of their main features about the weevils species and the methods to protect the rice from these insects.

Rice weevil facts

1. Appearance and size

Rice weevils are tiny creatures mostly found in rice. The adult weevils are 2-3mm in length whereas others are much smaller. The color of adult rice varies from reddish brown to black. They often have asymmetric and round shaped pits on the thorax and yellowish or light red four spots on their wing covers (elytra).  The rice weevil is much similar to other weevils, though they are easily distinguishable by the small orange-reddish patches present on their bodies.

The larvas have no legs, and they are white-creamy in color. They also have a unique head capsule that the adults lack. The chewing mouthparts are also present at the end of their heads to chew food. The other important fact about rice weevils is that they can fly and light attracts them as compared to the darkness.

2. Diet, behavior & habits

Weevil Insects eat rice grain.Since rice weevils live in the stored products like rice, wheat, and grains. Therefore, they consume these stored items as their diet. The adult insects chew the cereals and rice kernels. You will notice the small holes in the rice and grain seed; these are because of the chewing habit of rice weevils. Aside from this, if they are present outside your homes, they may eat plants and leaves. However, the larva live inside the kernels hence, getting their diet inside the beans. The rice weevils were firstly originated from Indo-Malayan region and with the trade of rice, they are now found all over the world.

You will not see the rice weevils outside your homes. However, once they enter your home and reside in your rice drums, then you will find many of them crawling on the walls and floors of your place. They are not dangerous medically and do not bite or cause infections. Still, they can cause severe damage by destroying the food.

The lifespan of rice weevils is of 4-6 months in average. When the rice weevil dies, it usually draws legs close to its body.

3. Reproduction

The adult weevil can fly quickly from one place to other. It does not mean that they travel long distances. The lifecycle of weevils is about 30 days. The healthy adult female can lay four eggs per day and 300-400 eggs in its whole life. The female bore in the kernel and lays the eggs there. The eggs usually hatch on the third day, and larvae live inside the seed for 2 and a half weeks. During this time, they get their diet from inside the kernel. The whole stage is called larval stage. After this, the pupal stage starts which lasts for 5-16 days, six days on average. Once this stage ends, the adult comes out of the kernel when the cuticle matures and is hard enough.

4. Rice weevil bites

The rice weevils are the type of beetles, yet they are not harmful and dangerous to human beings. Neither they spread any disease/infection, nor they bite the people. Still, they can be a threat to us in a way that they damage the grains and rice that we keep in our pantry. Not only this, but they cause severe agricultural loss by attacking the crops.Close up of weevil destroy rice.

5. Rice weevil infestation

The rice weevil lives on the rice and grains, chewing and damaging the food. In the can or where you have stored your rice and other grains, you might have seen the powder form of the seeds there. It is due to the rice weevils. These tiny creatures leave the flour, and half ate seeds after chewing the food.

These creatures attack the fields and in vast number. They are capable of destroying the crops like rice, wheat, and maize. There have been many cases from past decades when these pests have attacked the fields and destroyed the enormous amount of crops. They can even damage the yields even before the harvest action. When we try to grow in the infested area, the larva living in the soil destroys the crops. So you must make sure that the area is free of rice weevil or any other pest before you plant seeds or plants.

How to get rid of rice weevils?

Although rice weevils are not dangerous for human health still, they are a significant threat to your rice and other grains. Finding these pests in your rice can give you very annoying feeling and cleaning the rice before making can be difficult. If you had rice weevils at home and tired of them, then don’t worry. We will discuss here some ways to get rid of them.

1. Place sticky traps

Yellow sticky card trap in mid air.There are various types of sticky traps available in the market. Since these pests are attracted to light more than the darkness, therefore, when you pour rice from jar to some tray, the weevils tend to move outside. What you have to do is place the traps around the edges of the dish or bowl. When the insects try to run out of the utensil, they will automatically stick to the trap. These pests are not vigorous enough to free themselves from the trap. Hence they will die sticking to the trap.

2. Pour a pot of boiling water

The other way through which you can remove rice weevils is by pouring the hot water on the rice. Just like humans, these pests also needs particular environmental conditions for their survival. The boiling water can burn us badly so think about that; then you can imagine what it would do to those tiny creatures. Running a boiling water over the rice will kill all the weevils and the eggs. The dead will start floating on the surface of the bowl, and you can easily remove them. The method is suitable for a small quantity of rice and when you have to cook them.

Other than running hot water, you can also heat the rice at high temperatures killing all the weevils and their eggs. Using the boiling water techniques, you will clean the rice quickly and make them weevil free.

3. Freeze rice for at least one week to kill eggs

Freezing the rice will serve the same purpose as pouring hot water or heating. For, the insects can not survive in extreme cold environment. You can store the rice in the freezers to avoid these pests. If you do not have enough space in your freezer, then place in small quantities every week and freeze them for a week so that there will be no more eggs or weevils in the rice.

Effective rice weevil prevention

Every one of us has heard this proverb that prevention is better than cure. However, most of us are too oblivious to the surroundings, and we wait something to happen so that we can take action. Same is the case with the rice weevil problem. At first, we do not take precautionary steps, and because of that, we have to suffer.

Here are some effective tips for rice weevil prevention that you must consider to avoid issues later on.

1. Inspect upon purchase

When you go to store to buy rice, you should always inspect them. Do not buy if you find any weevil because there are high chances of reproduction of weevils.

2. Buy rice in small quantiy and consume within a realistic period

Instead of making our work easy what we do is we buy rice and other grains in significant quantities. However, we do not know; we are inviting the rice weevils. These insects tend to reside in the food that is not used for a long time. So always buy the rice in small quantity which easily consumable within a realistic time.Raw rice in a jar isolated on white background with clipping path. 

3. Store rice in the small firmly sealed metal, glass, or durable plastic containers (not the bags)

When you purchase the rice from the market, make sure you store them in the sealed glass, metal or plastic containers instead of bags. The reason for forbidding is that rice weevils can drill the shopping bags, therefore, finding the way to their target. They can also attack the rice when the lid of the pot or jar is not properly closed or air tight.

4. Regularly clean pantry cracks, crevices, and shelves

The other way you can prevent these weevils from residing at your place is by keeping the pantry cracks and shelves tidy and clean. This way you will prevent not only rice weevils but also other little insects like ants and cockroaches. Since they are tiny in size, so they can quickly lay their eggs and even reside at such places.

5. Place Dried chilies around the pantry

Putting the dried chilies around the pantry repel these weevils. It is a natural way and not even harmful. All you have to do is take some dried chilies and place around the pantry. The smell of these chilies is too strong, and it will repel all the insects including rice weevils. You can also wrap them in a thin cloth and place in the jars where you have stored rice and grains.

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