The birch is a large deciduous tree that can reach, depending on the variety, up to thirty meters in height. It is characterized mainly by its triangular-shaped light green leaves and its whitish bark. In autumn with its yellow leaves this plant offers a decoration in any landscape. In this article we will talk about the yellow leaves on birch trees, but when this yellowing is due to other factors, not just the autumn cold.
We will try to make it clear what are the main causes of birch leaves turning yellow and we will discuss how to treat and/or prevent this from happening. We’ll also take a moment to discuss birch leaf browning. But to start this publication we will see how to identify birch trees by their leaves.
1. Birch Tree leaf easy identification
Next we will see point by point everything you must observe to identify a birch by its leaves.
- Shape: This is definitely the first thing to look at. All Abnedul leaves are oval and end in a very pointed tip.
- Edges: The margins of the leaves are characterized by being toothed or weakly toothed. The leaves are said to have small, fine teeth at the edges.
- Leaf veins: Birch leaf veins are usually parallel and follow a pinnate (feather-like) pattern, curving gently toward the tip of the leaf.
- Size: This factor varies greatly from one species to another. But for you to have reach I can tell you that the size ranges between 3.8 and 10 cm long.
- Color: its color is bright green on the upper part, and paler on the underside of the leaf.
- Texture: The upper part has a smooth texture, while the back is usually more hairy in some species (it has small fine hairs).
- Arrangement: they are arranged alternately along the branch. In other words, a leaf is attached to each node, alternating sides as the branch progresses.
- Fall Color: During the fall, and before falling, the leaves turn a bright yellow.
Keep in mind that there are many species of birches. With the previous guide you will only identify if the plant is a birch or not, to determine what species it is you will need a more specific guide.
2. Yellow leaves on birch tree
Yellowing leaves on birch trees, a condition known as chlorosis, can be caused by various factors. It’s important to understand these causes in detail to effectively address the issue and promote the tree’s health. Here are some of the most common causes of yellow leaves on birch trees:
2.1 Nutrient Deficiencies
One of the main reasons why birch leaves can turn yellow is nutrient deficiency. Among the main or most common we can mention iron and manganese.
- Iron deficiency: You will notice when dealing with iron deficiency that the tissue between the veins of the leaves turns yellow while the veins remain green. Iron poverty in soil can be due to alkaline soil conditions, compacted soil, or excessive moisture. Let’s see how to deal with a problem like this.
Treatment: there are special fertilizers for these cases. They are chelated iron fertilizers. Depending on the evolution and improvement of the plant, it may be necessary to apply it annually, especially if the pH is high.
- Manganese deficiency: Manganese deficiency causes chlorosis in birch trees. So the symptoms are similar to a lack of iron.
Treatment: you can solve this problem by applying fertilizers rich in manganese or directly using manganese sulfate. Monitor soil pH levels as manganese availability is affected by soil pH.
2.2 Poor Soil Drainage
Birches need soils with good drainage capacity. If the soil where it is planted retains a lot of water, it can end up suffocating the roots, something that decreases their ability to capture nutrients.
- Treatment: the best in these cases is prevention. Before planting your birch, check the soil conditions. If it is already planted you can try to improve drainage conditions by adding organic matter such as compost.
2.3 Environmental Stress
Another very common cause for a leaf yellowing problem is poor weather conditions. These undoubtedly negatively affect the leaves of birch trees.
- Drought stress: Although they do not support very humid soils, they are not resistant to drought either. Lack of water can cause the leaves to turn yellow.
Treatment: as you can imagine the treatment is quite simple. It is enough to water deeply in dry periods. Make sure the soil has a small degree of humidity, but don’t forget to avoid waterlogging.
- Extreme temperatures: Extreme ranges, either very hot or very cold, can cause leaf yellowing. Late frosts or very strong heat are the most damaging.
Treatment: one way to regulate soil temperature is by applying a mulch of organic matter. It is advisable to water the tree well during heat waves.
2.4 Root Damage
It is common that due to excavations you cause damage to the roots of your birch. These damages stress the plant, and in some cases can lead to the yellowing of its leaves.
Treatment: the best in these cases is prevention. In other words, avoid placing any constructions near large plants like these. If you have already caused the damage, you can water and fertilize to reduce the stress of the plant.
It is normal for birch trees to lose their leaves in the lower canopy as they age. You don’t have to worry about this
Treatment: it is completely natural, so it does not require any treatment.
2.6 Pest and Disease Issues
There are several pests that can affect birch trees and cause the leaves to turn yellow. The most common are the bronze borer, aphids or other diseases such as leaf miners or some fungal diseases.
Treatment: depending on the pest that is treated, the treatment will be different. Some effective treatments are the use of insecticides, fungicides or applying cleaning pruning. It is important to be vigilant and identify the pest in time.
2.7 Nutrient Imbalances
- Cause: Imbalances in soil pH or nutrient levels can affect a birch tree’s ability to absorb nutrients.
- Treatment: Conduct a soil test to determine nutrient imbalances, and adjust soil pH or add specific nutrients as needed based on the test results.
To effectively treat yellowing leaves on a birch tree, it’s crucial to identify the specific cause in your particular situation. Consulting with a certified arborist or a local horticultural extension service can provide expert guidance tailored to your tree’s needs.
3. Newly planted birch tree leaves turning yellow
There are many reasons why a newly planted birch tree may suffer from yellowing of its leaves. Below I will list the most common causes:
- Transplant shock: It is normal for any plant to be transplanted to suffer a high degree of stress. This is commonly known as transplant shock. Depending on the degree of stress, its leaves may turn yellow and some may drop. Proper care is necessary to mitigate this stress.
- Poor soil quality: before transplanting your birch you must make sure that the soil is good. By good, I mean that it does not have nutrient deficiencies, inadequate ph levels or high water retention. As we already studied in the previous section, these are key factors for the health of birch trees. It is best to carry out a soil analysis if you are not sure of the characteristics of the soil.
- Fertilization problems: It is common that as soon as we plant our birch we think that it is good to fertilize it. But normally these plants do not require fertilization and excessive fertilization can seriously damage them. Signs such as the yellowing of the leaves are common in these cases. If you fertilize, make sure you don’t overdose.
- Improper planting: When planting birch, it is key to not only check the quality of the soil, but also to plant it at the correct depth. If you plant your birch too deep or damage its roots it is normal to stress it and cause the leaves to turn yellow.
- Environmental stress: if the weather at the time of planting the birch is having extreme factors such as high temperatures, strong winds, the plant may suffer stress. Better to wait until the weather improves to plant it, and give it all the protection you have at hand to reduce possible stress.
- Little sunlight: birch trees need many hours of sun a day. So you must choose a suitable place, if you plant it in a place with a lot of shade the leaves may turn yellow.
As you have seen, there are many possible causes for the leaves turning yellow on newly planted birch trees. Take the time to identify what the problem is and treat it accordingly. Generally, with proper care, the birch will recover and begin to grow without problems.
4. Birch tree leaves turning brown in summer
I did not want to end this post without analyzing the situation in which birch leaves turn brown in summer. When talking about problems in the leaves of this plant, it is a highly consulted situation, so we will analyze it briefly. You will see that the causes and treatment are similar to the yellowing of the leaves.
- Drought stress: summer is the season in which birch trees need the most water. So if you stop watering and the birch suffers from drought, its leaves can suffer. Keep in mind that birch trees have shallow roots and are sensitive to drought.
Treatment: as always this type of problem is easy to solve. You just have to water more regularly in these hot times, especially if it hasn’t rained. You can cover the base of the birch with a mulch to help retain moisture.
- Excessive heat: depending on where you live, summer can deliver very hot days. On days with extreme heat, birch trees can become stressed and their leaves can turn brown from sunburn.
Treatment: if the birch specimen is small, it can provide you with something to spare during these days of intense heat. In addition, abundant watering will help lower the temperature of the soil at its base.
- Fungal diseases: Some fungal diseases can cause brown spots on birch leaves. Some of the most common are anthracnose or leaf spot.
Treatment: among the fastest and most effective treatments is the pruning of the affected branches. This will not only eliminate the source of the infection but will provide better air circulation within the foliage. You can also apply some suitable fungicide for the disease in question.
- Nutrient Deficiencies: Birch trees can have brown leaves if they are lacking in essential nutrients, especially nitrogen, or micronutrients like iron or manganese.
Treatment: the ideal is to know what nutrients the soil has through a soil analysis. With this you will know if there is a deficiency and you can apply some fertilizer rich in the missing nutrient.
- Age and natural leaf fall: Finally, it is important to keep in mind that birch trees naturally lose their leaves. It is something of nature and you do not have to give any type of treatment.
Treatment: No treatment is necessary for normal leaf drop due to age.
To determine the exact cause of the browning leaves on your birch tree and the appropriate treatment, it’s advisable to consult with a certified arborist or a local horticultural extension service. They can conduct a thorough assessment and provide specific guidance tailored to your tree’s situation.
- Birches The Important Distinctions – maine.gov.
- Birch identification: A simplified guide – plantnetwork.org.
- Grow and Maintain a Healthy Birch Tree – fs.usda.gov.