Curculio Control: How to Identify, Prevent and Get Rid of Curculios

Conotrachelus nenuphar, plum curculio, or simply curculio is originally from Minnesota. It is an injurious pest in different North American states, as well as in some parts of Canada. Early detection and control are necessary to lessen its damages, which can even lead to economic loss for commercial growers. With this, it is critical to be familiar with how to get rid of curculios.

The eggs of curculio are small, oval, and white, which you can find on the surface of the fruit of their host plant. Upon transforming into a larva, it develops a curve body and has a brown head. It is also legless and had an average length of six to nine millimeters. Once they fully transition into an adult, on the other hand, the length is ¼ inch. They have a back that is gray or brown. One of its distinct characteristics is the presence of bumps on their sides. Also, they have a protruding snout, which is about ¼ of the overall length of their body.

Curculio Nucum

A Curculio Nucum on Hazelnut

Curculio’s Habitat

The principal habitat of curculio includes cultivated and agricultural lands. They can also be present in the garden if you have some of their most common host plants, which we will discuss in the next section. Their first appearance in the orchard will most probably be after the first fruit bloom or when the temperature reaches a minimum of 70 degrees Fahrenheit. Most of the feeding activity appears on the buds, blossoms, and petals. The eggs are usually laid on the fruits, especially when they grow at least ½ inch in diameter.

Identifying Curculio’s Damage

Plants Affected

Curculio has a diverse range of hosts, which include those that belong to the Rosaceae and Ebenaceae family. To be specific, some of the most common host plants include plum, apple, cherry, persimmon, quince, strawberry, stone fruit, apricot, peach, blueberries, gooseberry, currants, and grape vine.


Watch out for the following signs, which can be obvious indications that curculio is present:

  • The fruit is one of the parts that will demonstrate the extent of the damage. The symptoms will depend on the type of feeding. For external feeding, there will be scars outside the fruit. On the other hand, in the case of internal feeding, there will be holes or punctures. These are indications that the curculio penetrated the fruit.
  • Fruit droppings is another symptom you should watch out for. Because of the feeding on the fruit, it does not receive the nutrients that are essential for survival. It becomes weak, and eventually, it will fall off the tree.
  • When they are adults, on the other hand, it is possible that there are marginal damages that will be evident on the blossoms and leaves of the host plant.

Results of Infestation

There are many things that can happen to a plant or fruit once it shows visible signs of infestation. Among others, one of the most common is that they will be unfit for human consumption. The larvae will feed on the fruit at an early stage even before the fruit grows. It stays on the flesh of the fruit while it is developing, which will cause it to rot as it ripens. It leads to the reduction of crop yield, and consequently, financial losses for commercial growers.

Curculio Damage

Young Apple Damaged by Curculios

How to Get Rid of Curculios

Natural and Organic Solutions

The best way to eliminate curculio is through natural solutions. They are not only effective, but also safe. With this, the following are some of the things you have to do:

  • Among others, physical removal is one that can be effective. This is an exhausting task, which is why it is best only for small areas. You can shake the tree and in turn, the eggs will fall. Handpick the eggs and throw them in a bucket of soapy water. The same thing is true in the case of larvae and adults. Be attentive as they look like the bark of a tree, making it quite challenging to spot their presence.
  • If you have chicken at home, it will also be good if they are under the tree when you shake its branches. They will help to get rid of the pest rather than picking them up manually. Also, consider putting a board on the surface so that it will be easy to collect the curculio.
  • A lot of people may have hesitations with the use of insecticides because of the belief that they are toxic. Yes, the latter can be true, but not in all instances. There are pesticides that use organic ingredients. Kaolin is the perfect example of the latter. It is a soft and white clay that will act as a protective barrier when applied to the host plants. It must cover the tree liberally so that it will be effective.
  • You also need to clean the area where there are trees that are prone to infestation. Take out any decaying fruit. Chances are, it contains curculio. If they stay on the ground, the pest can easily transfer to the tree or to another host.

Chemical Solutions

In many commercial plantations, chemical sprays are on the top of the list when it comes to the control and elimination of curculio. This is a solution that is common in large-scale infestation. To yield the highest level of success, proper coverage is necessary. Be sure to target the specific parts of the plant where this pest survives. The problem with chemicals, however, is that they are toxic even to natural predators. They can also harm your pets or the environment in general.

To be specific, some of the best chemicals that will deliver positive outcomes include Imidan 70W, Actara 25WG, Exirel, and Esteem, among others. They have active compounds that will kill curculio even before they can wreak havoc.

How to Prevent Curculios

One of the best preventive measures is to keep the surroundings clean. Inspect the plantation or garden often, making sure that there are no signs of damages by curculio. If there is a fruit that falls off the ground, take it out as soon as possible. Also, be sure to pay attention to maintaining the health of your plants, providing you with the assurance that they will be more resistant to problems from curculio.

Leave a Reply