Within the citrus family, the orange tree is without a doubt the most popular fruit tree, along with the lemon tree. The production of this vegetable can be very numerous, as long as the conditions are appropriate. As for its fruits, oranges, are widely used throughout the world, whether for cooking, making juices, eating them as they are and for baking. The structure of this citrus fruit is strong and Thanks to various studies that have managed to generate hybrids, orange tree pests are much less problematic since it has become more resistant.
However, the pests of the orange tree continue to exist and no matter how resistant it is, at some point it can be affected. For this reason, it is essential that we know what pests can affect this citrus fruit, how to detect them and what treatment is indicated in each case. So if you are thinking of growing orange trees or you already have any of these fruit trees, I recommend that you keep reading.
The most common pests of the orange tree
Before talking about orange pests, we are first going to explain exactly what is considered a pest in agriculture. As well, this term refers to all those microorganisms, animals and plants that cause a negative effect on crops. For pests to thrive, they need a reliable, concentrated source of food. Generally, the measures that are used to increase the productivity of vegetables in cultivated fields create a quite favorable environment for pests. These measures are usually the following:
- Monocultures of varieties whose production is high.
- Fertilizer use.
- Reduction or elimination of rested soils for multiple cultivation.
When talking about orange tree pests, the most common are thrips, whitefly, aphids and citrus miners. Next we will talk about all of them and how to combat them. Later we will comment a little more the plague of mealybugs, which is the most frequent of all.
First of all we have the thrips. These are small insects that very frequently affect crops. The negative effect they have specifically on the orange tree is established in the fruits, that is, in oranges, when they are in full development phase. Regarding the focal point, this is on the calyx, that is, on the top of the orange. However, in more advanced cases, negative effects can be perceived throughout the structure.
What are they and how do you fight thrips?
As we have already mentioned before, thrips are a very frequent pest in all types of citrus. These small insects live in the flowers of trees, where they do not cause visible damage. They begin to attack after the petals fall, That is when we must be more careful and more attentive to assess the state in which the plants are.
To eliminate thrips we must use a specific pesticide indicated for this species. Of course, it is very important that we consider what is the right time to apply it, to avoid damaging other microorganisms.
Another of the most common pests that usually affect the orange tree is the white fly, which also turns out to be one of the most worrying. It is not because of the whitefly itself that it is a very alarming plague, but because considerably facilitates the appearance of a fungal disease known as «bold«. In addition, it attracts other pests, such as mealybugs. Therefore, early treatment will be vital for the orange tree.
Whitefly on citrus. Symptoms and Treatment
It is the adult whitefly that generates the main action, which consists of production of a substance called honeydew on the back of the leaf. A fairly simple way to detect this plague is by looking at the behavior of the ants on the tree, since they are equally attracted to the molasses.
There are some natural treatments that we can apply both to eliminate and prevent the whitefly plague. On the one hand we can wash the vegetable with mild soap, if it is already affected. Another idea to treat and also to prevent this pest is plant repellent vegetables in the surroundings, such as calendula. If natural treatments are not enough, we will always have the option of using an insecticide, if possible ecological.
Aphids are also part of the most common orange tree pests. These tiny insects represent a family made up of several different species, at least four of which are very common on orange crops. Similar to whiteflies, aphids also produce honeydew on leaves. They create this molasses through the suction of the sap, on which they feed. Therefore we can deduce that they also facilitate the appearance of bold and other pests, such as cochineals.
There are several ways to prevent the appearance of aphids. It is very important to prevent wounds from being created on the plants. Therefore, we must make sure to do gentle pruning and only what is necessary. Another way to prevent this pest, the most efficient, is by natural enemies of aphids. However, if the outbreak is too large and the damage impossible to control, biological action is the most recommended. Of course, whatever the case, the application of biological or chemical products must always be very well controlled and only use those that are approved by the agencies in charge.
We cannot forget the citrus fruit miner worm. Its larvae invade citrus leaves, creating shallow tunnels and feeding on them. As its name indicates, this pest is much more common in citrus fruits, such as orange trees, lemon trees, etc. than in other plants, but they can also appear in closely related plants, such as calamondine y kumquat.
There are other miner-type pests that attack ornamental plants, crops and weeds, but they mainly affect the stems and fruits of vegetables. Curiously, the only leafminer that tunnels into citrus leaves is the citrus leafminer.
How to treat cochineal in orange trees?
Among all the pests of the orange tree, the ribbed mealybug is the most frequent. It is a parasite that feeds on plants, causing malformations in the leaves and chlorosis, even drying out the infected branches on some occasions. In addition, the loss of sap suffered by the affected plant can harm its productivity and growth. It should also be noted that mealybugs, being suckers, They can transmit viruses to vegetables by biting them.
As with aphids and whiteflies, also mealybugs they secrete molasses. This substance attracts ants and promotes the appearance of the black. At this point, we can use a copper-based fungicide to combat this fungal disease.
When it comes to controlling cochineal, or any other pest that can affect our crops, it is best to leave pesticides as a last resort, They are very harmful to the environment and to health. In addition, in the long run it is possible that we cause the opposite effect, since the useful fauna of the environment would be eliminated.
If we are lucky and the infected surface is not very wide, We can eliminate the cochineals manually or by pressurized water. The best thing we can do is prune those parts of the vegetables that are most affected and lighten the crown a bit. In this way, insects are more unprotected against atmospheric conditions.
There is also the possibility of treating this pest with potassium soap diluted 2% in water. It is a biological insecticide that is harmless to people. With this treatment we will not only combat the plague, but we will also clean the molasses residues, thus preventing the appearance of black.
Natural predator: Rhodolia cardinalis
It is almost impossible to completely eradicate the ribbed mealybug. However, we can try to keep the population controlled, specifically below a level where the damage is harmful. Using biological control methods are usually very effective. In the case of this plague, there is a natural predator that feeds practically only on this species. Is called Rhodolia cardinalis and, despite being originally from Australia, today it is a worldwide ally in citrus cultivation. Currently we can find this natural predator of the cochineal in areas with mild winters. However, there is the possibility of buying it.
What is corrugated mealybug and how to get rid of it
It is a beetle with a length of approximately three millimeters. It is quite similar to the seven-spot ladybug, but smaller in size and with black and red spots instead of spots. Cardinal Rhodalia It has an extraordinary fertility, being able to have up to six generations. It feeds on mealybugs throughout their biological cycle, thus becoming a voracious predator of this species. The only drawback when acquiring this insect is that does not tolerate harsh winters.
In the event that we decide to introduce Rhodolia cardinalis in our crops we must avoid the presence of many ants and also the application of broad-spectrum insecticides, because both would end up with this beetle.
Taking into account everything we have just learned about orange pests, we are now able to identify and treat the various attackers, even prevent them. Remember that it is very important to monitor and observe the plants to detect any pathology as soon as possible and put a solution to it.