Belonging to the family of Chrysomelidae, their eggs are cigar-shaped and they have orange-yellow color. The larvae, on the other hand, have a dark-brown head and they are C-shaped. When they turn into adults, meanwhile, they grow to an average length of six to seven millimeters. The color is black to brown and they are recognizable with a zigzag white line on their back. They also have a slender body. Another noticeable characteristic is the crescent-shaped white tip that you can find on their abdomen.
Pea Weevil’s Habitat
The habitat of pea weevils, similar to the case of other pests, will depend on its specific stage of development. You will find eggs outside of the developing pods of the host plant. On the larval stage, on the other hand, they feed on the nodules of the plant. This is where they stay for at least six weeks and they undergo five instars. The pupation stage takes place in the soil. After this, a new generation of adults is born. Generally, they emerge on the last week of July, with peak in the middle of August. They are more active during the spring months or at least when the temperature reaches an average of 20 degrees Celsius.
Identifying Pea Weevil’s Damage
The following are some of the most common indications that pea weevils are present:
- The seed of the host plant will show most of the damage. Since the larva will be the most destructive, there will be round holes, which will be their entry point.
- The adults, meanwhile, will feed on the leaves of the host plant. Most of the symptoms will be apparent from May to June. They will chew the edges of the leaf, making the edge notched or scalloped.
- Pea weevils will also feed on the roots of their host plant. It inhibits the fixation of nitrogen. In turn, this limits the nutrients that the plant receives. In the end, this can lead to rough stress, reduction of crop yield, and poor growth of the plant.
Results of Infestation
During severe cases of infestation, the damage from pea weevil can be devastating. It reduces germination by up to 75% and seed weight by at least 25%. The larva is the most destructive stage of the plant and is the one responsible for economic damage or profit loss due to the destruction of the crop even before they reach full maturity. For established plants, they are more resistant to damages, which is why most of the problems will be apparent with the young ones.
How to Get Rid of Pea Weevils
Natural and Organic Solutions
The elimination of pea weevils is possible through natural solutions, including those that we will list down below:
- On the top of the list is manual control. You have to handpick the pea weevils. This will work best if you only need to treat a small area as this can be an exhausting task. Also, it is most effective if you remove the eggs before they hatch. When you take them out from the host, be sure to throw them away in a bucket of soapy water. This will kill them in an instant.
- Using a garden fabric or row cover is one of the best ways to get rid of pea weevils. They will provide a protective barrier on the top of the host plant. However, you have to remove the cover when the plant reaches its six-leaf stage. You need to take it out to encourage pollination.
- A no-till system is also a promising solution for the prevention of pea weevils. The fields with a no-till system will be less susceptible to infestation as against those that undergo conventional tilling.
- Do not be afraid to use insecticides, but be sure to limit them to those that are organic. With this, one of the best solutions is the use of diatomaceous earth. The latter is made from naturally-occurring fossil remains that are effective in killing the weevils. They have microscopic edges that will destroy the body of the insect upon ingestion. It does not harm other mammals. However, be careful not to inhale it during application so as to prevent problems.
- For biological control, you can rely on the use of beneficial insects and natural predators. You can either buy these predators or encourage their presence in the garden through making the external environment more attractive for them. For instance, you can grow plants that they find attractive. Some of the best predators to have include ground beetles, braconid wasps, predacious bugs, assassin bugs, and robber flies, among others.
There are many pesticides containing certain chemicals that can also prove to be promising. However, a lot of people tend to stay away from this solution because of its toxicity. In most instances, it will not only kill pea weevils, but affects even beneficial insects and natural predators. Sevin is one of the best products that can help in controlling the population of pea weevil. Its active ingredient is Carbaryl. Make sure to spray them the right way. Follow the instructions from the manufacturer and wear the right protective gear to avoid harmful effects of the chemicals.
How to Prevent Pea Weevils
Monitoring is one of the first things to do for the prevention of pea weevils. The earlier you are able to detect the presence of this pest, the more likely you will succeed with your choice of control and elimination and procedure. You have to deal with the pest before they transform into larvae, which means that you should remove their eggs from early on. Keeping the garden clean is another preventive measure that will yield a high level of effectiveness. Keep it free from decaying vegetation or plant debris as they will encourage the presence of pea weevils. It will also be good to consider planting resistant varieties so that infestation will not be an issue.