The walnut tree is a deciduous tree, which means that it has deciduous leaves that fall at certain times of the year. These trees renew their foliage, but They lose their leaves in the colder seasons such as autumn and winter.
It is a large and very vigorous tree, with a very spreading crown, the trunk can reach up to 2 meters in diameter and mature trees have a smooth silver-grey bark.
Its leaves have an oval shape in a bright green tone.
The tree produces flowers in clusters where the edible fruit develops. The kernel of the walnut is protected by a corrugated woody shell. These trees can live for periods of more than 200 years and can be called persian walnut, English walnut or common walnut, is native to central Asia.
The walnut tree and the walnuts
Walnuts have many benefits as they are a source of antioxidants and vitamins. Among which the following stand out: vitamin E, vitamin B1, B2, B3 and B6, which are involved in the proper functioning of the brain.
But, we have to keep in mind that all trees have the potential to suffer from diseases, pests and insect damage. In addition to intervene in factors such as location and climate that will influence problems and diseases that we must know in order to prevent them or provide appropriate treatment.
This article will explore these causes and give you some tips on how to recognize, treat and prevent the problem to keep your walnut trees healthy and productive.
Causes of walnuts turning black
One of the most worrying problems is that the nuts can turn black, which can indicate various problems that the tree has. Below, we will look at possible causes and how we can treat and prevent it.
fungal diseases
One of the most common reasons for walnuts turning black is fungal diseases. Two of the most common are walnut blight or black plague and bacterial canker.
Walnut blight: It is a very destructive disease that begins when sprouting occurs, affecting the tissue and high humidity and the presence of rain favor its development.
It begins to be noticed in the first nuts that become oily and then a black color, surrounded by a halo that appears in the first sprouts. These fruits fall prematurely and are not suitable for consumption. In addition, the tree may also lose leaves prematurely.
The treatment for this disease is to apply copper sprays every 7 to 10 days in June and July which can greatly reduce the disease.
Bacterial cancer: It is a common disease in walnut trees caused by a fungus and can be detected by the black spots that appear on the fruit in winter.
In spring they do not sprout, they become deformed or grow withered shoots.
It can also affect the roots and The fungus can attack and cause wounds or lesions.
To prevent these diseases, It is very important to keep your garden clean and prune the trees properly. to promote airflow and reduce the possibility of infection.
Fungicides can also be used to help control the spread of these diseases.
Damage caused by hot weather
Higher than normal temperatures can cause walnuts on walnut trees to turn black, and this can be especially common on mature trees.
When temperatures are especially high, the tree's nuts suffer heat damage. This can cause the nut's protective covering to blacken and become damaged, affecting the nut's nutrients.
To prevent this from happening, You must provide the trees with plenty of water to keep them well hydrated.Also keep branches and foliage well pruned to allow air passage and shade the tree during hot weather to protect the nuts.
Environmental stress
Environmental stressors, such as very high humidity or severe drought, can also cause walnut nuts to turn black.
In these cases, Nuts are likely to blacken or discolor, and may eventually develop black spots.
This is because when the tree is under stress, it produces higher levels of chemicals in an attempt to protect itself.
These chemicals can cause walnuts to turn black. To prevent this problem, it is crucial Keep your orchard well watered and well fertilized to help reduce the tree's overall stress level.
Also, avoid over-fertilizing, as this can also increase the tree's stress level.
Treatments for blackened walnuts
When you notice that your walnuts are blackened or discolored, you can use a number of treatments to try to improve the appearance of the walnuts.
First, it is important to remove affected nuts as quickly as possible to prevent the problem from spreading.
To make sure the problem has been resolved, also You can apply a fungicide to the affected area to eliminate any remaining fungal spores.
It is also a good idea to prune any branches that appear unhealthy, as this will help improve airflow and, most importantly, prevent the spread of disease.
Prevention for blackened walnuts
A good way to prevent disease and keep nuts from turning black is to provide the tree with good care and to be careful about checking it regularly.
- Keep the garden clean and the tree well pruned to promote air flow.
- You should regularly check that the garden receives water and fertilizer, which are essential nutrients for the tree to remain healthy and stress-free.
- It is also a good idea to avoid over-fertilization, as they can increase the tree's stress levels.
- Lastly, it is important Regularly inspect the orchard for signs of disease, and if any problem is detected, act quickly to solve it.
In general, having black walnut nuts can be a cause of great concern as they cannot be ingested and utilized to get all the benefits that the nuts provide you.
To help keep walnut trees healthy and productive, It is important to pay close attention to your overall health and provide them with appropriate care.
Also, regularly inspecting your orchard and acting quickly if you detect any problems is the best way to prevent pests and diseases. Giving your walnut tree the care it deserves is essential. That way, you can get the benefits and nutrients from walnuts without problems all year round.