Weevil: 9 General Types and How to Get Rid of Them
Weevil is a name commonly use for specific beetles that belong to the family Curculionidae or snout beetle family. Weevils contain more than 60,000 species in total, and the family Curculionidae contains the maximum number of species among all beetles’ families. According to one research, there are more than 1000 species of insects from the family Curculionidae is present in North America. They are usually very small in size, and the body size varies from just 3 mm to 10 mm in total. Weevils’ species exhibits a wide range of body shape and colors. Their body shapes are oval or lean, and body colors are usually dark like gray, reddish-brown or black. However, few weevils’ species have also bright, intense colors. Their body may also contain scales or shiny hairs. The most noticeable feature of adult weevils is their head shape that is elongated enough to make a snout-like shape. This is the reason they are sometimes also known as ‘snout beetles.’ Few weevils also contain a snout that is equal in length with their remaining body. The mouth of weevils is present at the tip of snout. Though almost all weevils contain snout, however, there is a family called Bruchidae that doesn’t contain snout. The curved antennae of weevils are located at the center of the snout. Another remarkable feature of weevils is their spurs that are present on the femur of both front legs.
Table of Contents
- What Do Weevils Eat?
- Weevil Lifecycle
- 9 Types of Weevils
- Damages Caused by Weevil
- How to Get Rid of Weevils
What Do Weevils Eat?
Weevils are herbivores by nature, and they feed entirely on plants from larval phase till they reach their adulthood. Little larvae of many weevil species only feed on specific types of plants parts like seeds, fruits, flower head, root or stems. These larvae either eat a single type of plant species or those species that are strongly related to each other. However, adults prefer to eat from different plants. They have a habit of consuming a wide variety of plants and grains. While eating, their snout helps them a lot. It assists not only in eating plants and penetrating the different eating material but also in drilling holes. As weevils can be fed on the variety of plants parts, grains, and crops, therefore, they can also be proved as very destructive insects too. They consume important crops and grains and destroy them. Different species of weevils consume different types of grains and crops that result in a huge economic loss.
Weevil lifecycle varies from species to species. Few species of weevils lay their eggs during spring. They lay eggs on the ground close to the host plant. The larvae hatch from eggs and feed on the roots of plants while staying underground. This is the reason; people can hardly see them. There are other weevil species, which stay underground during winters and comes out of the ground on subsequent summers. Those larvae that come above the surface during fall and summers attacks home mostly for shelter.
9 Types of Weevils
There are a variety of weevils that consume different types of crops and grains. Here, we will discuss types of weevils.
1. Boll Weevil
Boll weevils whose scientific name is Autonomous grandis are those weevils who fed on buds and little balls of cotton plants. Their body size is only 6mm in length. Its diet consists entirely of the cotton plant that results into reduced fibers of plants. Due to this reason; they are considered very dreadful for any country. Boll weevils hibernate in winters and before hibernating they produce many further generations.
2. Flour Weevil
Another destructive weevil is flour weevils that belong to the Family Tenebrionidae. Their name contains word weevil, but in reality, they are not right weevils. This insect is assumed as red flour beetle or confused flour beetle. Their bodies are quite oval in shape and have a body length of 3 to 4 mm. Their body has metallic touch with a reddish-brown color. Red flour beetle and confused flour beetle looks similar regarding their behavior and appearance. However, the only difference lies in the shape of their antennas. As their name depicts, their diet relies mainly on flour and other stored edibles. They can not consume other whole grains. Consequently, they can be found in different dusty minced products like flours, powdered milk, cornstarch, and cake mixes.
3. Rice Weevil
Rice weevil also is known as Sitophilus Oryza is a type of weevils that like flour weevils contain reddish-brown body color. Their bodies are 4 mm long and wings contain red or light yellow color patterns. Their snouts are long and can reach the length of 1 mm. They do not bite humans or irritate them directly, but they cause serious problems with their troublesome eating habits. Unlike their name, they consume not only rice but also a huge variety of other grains too. They can consume wheat, oats, corn, rye and whatever grain they found resulting in serious grain loss.
4. Bean Weevil
Bean weevil is also known as Acanthoscelides obtectus like flour beetles are not true weevils. They rather belong to the team of seed beetles. Their bodies are slightly rounder as compared to wheat and rice weevils. Also, they lack the presence of snout that is a most remarkable feature of true weevils. Their bodies are intensely hairy with pale olive color along with dark-colored wings. Bean weevils can consume any available food. Their diet may include lentils, cowpeas, and other seeds. They usually consume beans in a hidden way, and it is very difficult to identify their presence. The only indication of their attack is the presence of empty beans covers among crops.
5. Wheat Weevil
Wheat weevil (Sitophilus granaries) also known as granary weevil, is notorious for its destructive perspective in agriculture. Their body size is usually less than 5 mm with dark brown color all over its body. They also contain extremely marked bumpy patterns on its head.Wheat weevils contain immature wings making them unable to fly. Because of this inability, they can usually be found consuming stored food products rather than those in fields. The adult wheat weevils also play dead on any interruption.
6. Black Vine Weevil
Black vine weevils that are also known as Otiorhynchus sulcatus can be seen in most parts of northern United Stated and exist in all over the state of Ohio. These weevils are 12 mm in length with ovoid body shape covered with plenty of little hairs. Their body color varies from brown to gray. Their snouts are quite smaller in size and wings possess small pits. They usually consume different plants, shrubs, trees and herbs. The food choices of adults vary from larvae. The adults feed on leaves and stem of plants, while larvae consume major roots. Therefore, it can be said that little black vine weevils cause more damage as compared to adults.
7. Rose Weevil
Rose weevils are also known as Merhynchites bicolor. Their body length varies from 5 to 6 mm in length with red and black color. Their snout is quite prominent and pointed making them able to drill holes. Their major diet consists of flowers. They make holes in flower buds and attain their food. Regardless of having a small sized body, these tiny creatures can cause a serious threat and irreplaceable loss to horticulturists. They are dangerous for horticulturists at their all stages of life. Adult rose weevils make holes in flower buds to get food and to lay eggs there, and larvae produced feed on flowers petal. Adult weevils also feed on stems and shoots of plant the if they do not get any flower buds.
8. White Pine Weevil
White pine weevils are also known as Pissodes strobi. Their bodies are 6 to 7 mm long with white and brown colored scales present all along their wings. They also contain long snouts. Their rust color body can easily recognize adult white pine weevils. As their name depicts, these weevils normally consume spruce and pine trees as major part of their diet. However, they can also be seen consuming lodge pole pines and black spruce. They start affecting trees by making holes in the bark of the tree. Like black vine weevils, their larvae also cause more damage as compared to adults because of their habit of consuming roots.
9. Cowpea Weevil
Cowpea weevil is also known as Callosobruchus maculatus. These weevils lack elongated snout with the body color of reddish-brown with gray or black marks. As their name shows, they feed largely on cowpea and accumulated soybeans. They also lay their eggs on beans on which they are feeding. The larvae produced also starts eating those beans while growing.
Damages Caused by Weevil
There are different species of weevils that attack different parts of plants like stems, barks, roots, flowers, seeds, and leaves. Besides feeding on plant parts and other edibles, weevils also lay their eggs on that food, which later on becomes the source of food for their larvae. In this way, the cycle of plant destruction continues. Different weevil species can attack grains, plants, beans, vegetables, fruits, seeds, cotton, and even stored food products. Besides attacking crop fields and open food sources, weevils sometimes also invade homes and consume food from different accumulated items. They can even destroy cereals, dry fruits, barley, cake mixes and other powdered items. They are very deadly pests and they can cause a huge economic loss for farmers and can be a source of great irritation for homeowners. Food once contaminated with by weevils should be discarded away as it can cause several infections and diseases if ingested by humans.
How to Get Rid of Weevils
Weevils become more active during summers and can create trouble for humans along with other pests. Therefore it is necessary to eliminate them as soon as possible from your locality. Otherwise, they can reproduce plenty of weevils and can make a situation even difficult for you. Here, we will discuss few tips to get rid of these tiny beasts.
1. Freeze and kill it
The best and reasonable way to kill weevil is to freeze your food. As soon as you buy any food item, freeze it for at least four days. Food can be stored in a freezer for the longer period. However, if there is a space issue, then four days (96 hours) with maximum coolness is enough to kill any larvae, eggs or weevils already present in the food. After four days, keep your food stuff out of a freezer, check it for dead weevils and store it in a normal place.
2. Bay or Neem Leaves
Another most effective and easy remedy to get rid of weevils is to use bay or neem leaves. They are easily available. If you do not have enough space to store food items in freezer or food item is stored in containers rather than in packets like flour, then it can work best for you. Normally, unsealed food is more vulnerable to pests attack. Therefore, put few leaves of bay or neem and put inside your container.
Cloves are another best remedy to get rid of weevils. Cloves are used almost in every other home. They have the sharp smell, and this is the thing that works effectively against weevils. To get rid of weevils, put few cloves on every corner and part of your kitchen where weevils are suspected. Try to cover all parts of the kitchen. Cloves sharp smell will force weevils to leave your area. Furthermore, cloves can be put in the jars of food items to eliminate weevils.
Another weird and effective tip to kill weevils is to use matchbox. Put the opened box of matchbox near the grains infested with weevils. The smell of sulfur will force weevils to leave your food items.
5. Keep the Infected Grains in Sunlight
The natural and free source of eliminating weevils from your home is sunlight. As weevils like dark and moist places to live, and light and heat are something, they would never like to face. Therefore, to get rid of weevils, put your infested food items in direct sunlight for a day or so. It will irritate weevils, and they will be forced to leave that place.
Other Home Remedies
- Cleaning your kitchen area properly and regularly can help eliminating these insects
- Flour sifter can be used to eliminate weevils
- Cleaning kitchen with white vinegar can also help in eliminating weevils
- Wet clothes trap can be used to attract insects towards cloth, and then they can be removed
No matter how small its body size is, they can cause a huge loss to whole agricultural fields and entire food storage. Therefore, it is necessary to take immediate steps to get rid of these tiny creatures.