As we know, there are numerous frosts that affect our crops, whether in gardens or agriculture. Today we are going to talk about a plague of great importance in fruit trees. Its about big-headed worm. It is an animal that is increasingly increasing its population and danger. In the region of Murcia, Valencian Community, Extremadura and Aragon is where it is having the most importance.
In this article we are going to tell you all the characteristics, biological cycle and danger of the big-headed worm.
The big-headed worm is a terrible pest that mainly affects fruit trees. Their populations are increasing drastically in recent years. They are considering what could be the origin of such an increase in population. On the one hand, the continued excessive use of herbicides and pesticides systemically reduces the predatory populations of the big-headed worm. This means that, with fewer natural predators, the worm can spread more easily without having as much risk.
We must understand that the food chain naturally works between predators and prey. If the human being intervenes in some of these links in the food chain, the ecological cycle can be broken. Normally the predators are smaller in an ecosystem due to the number of prey is limited and between the predators themselves compete. Once the prey stop having a predator that decreases their populations they begin to grow without restraintas long as there are sufficient resources to supply their needs.
In this case, we are talking about the artificially disappeared predators caused by herbicides and pesticides from humans. However, in cultivated fields all the resources to supply the needs of the big-headed worm are present. With the modernization of irrigation systems it is obtained from the land that is not so close to the tree is dry. Since part of the growth stage of the big-headed worm inhabits soils, its proliferation is more timely.
Life cycle of the big-headed worm
Let’s see what is the biological cycle of this pest of fruit trees. The adults remain mainly sheltered on the ground until the end of the summer. It is from this stage where they begin to emerge and coincide with the budding of the fruit trees. This is the reason why these crops are affected. The adults come out very hungry after all winter under the ground. This occurs more or less at the end of February and the beginning of March. They begin to devour all the shoots, buds and petioles that are in their path. After about 40 days of feeding they begin to reproduce. The breeding season extends from the months of May to September.
Spring and summer temperatures are milder for the pest, so each female can lay between 350 and 400 eggs on the ground and less than a meter from the trunk. The depth of the ground at which it lays the eggs is approximately between 0.5 and 2 centimeters. In just about 10 days the eggs hatch into the larvae and head towards the roots of the trees. Inside the roots they grow up to 7-10 centimeters.
Bighead worm identification
We are going to point out some of the main characteristics that the body of the big-headed worm has to be able to identify it easily. The adult of the worm is a large black beetle that is usually between 2- 2.5 centimeters. They are usually found on fruit branches and hide under the branches when it detects your presence. One of the aspects to recognize it well is that they fly away and flee if they think you have identified them.
It mainly affects all stone fruit trees. It is also proven that it affects other fruit trees such as chestnut, apple, pear and quince. The adult is the one that lives in the aerial part of the tree and feeds on the shoots and buds of the tree that emerge. However, the most important damage that the larvae can cause is to create galleries on the roots of the plants. This is where crops can be spoiled from the start. And it is that they are capable of destroying the cortical tissue and damaging all the sap ducts with which the tree feeds.
With the passage of time and the affection of these larvae, the trees end up very weakened and die.
Invasion control methods
There are several traditional methods to avoid pests of this worm in crops. For example, if we analyze the irrigation, if the ground of the trunk of the fruit tree is humid, the females do not carry out the laying on the ground. One recommendation is that the drip irrigation is placed close to the trunk to increase the humidity radius. You can use plastic that would act as a defense by surrounding the tree with a radius of at least one meter. This plastic is due and buried so that the worm cannot cross it through the subsoil.
Later, we collect the plastic when the invasion season passes. It is one of the most effective but less ecological operations, since it can generate plastic waste on the ground. Also, the moisture around the tree cannot extend much beyond the plastic and it can cause various excesses of humidity for other plants.
The removal of the infected tree is a task that should only be done in cases of great acceptance of the tree. It is convenient to proceed to its start-up and subsequent burning. Thus, we managed to avoid the spread to other fruit trees.
We can do a biological control, although there are still few measures and it is being investigated. Some fungi have been found that can become natural enemies of the big-headed worm, a beetle (Melanotus rufipes), a hymenopteran (Spathius erythrocephalus), Diptera (Sarcophylla latifrons y Billaea subrotundata) and entomopathogenic nematodes (Sreinernematidae and Heterorhabditidae). They all can serve as predators of the big-headed worm that introduced in a controlled way in ecosystems can help to reduce individuals.
I hope that with this information you can learn more about the big-headed worm and its characteristics.