Why Do Trees Get Sick and Die?

Trees can live for many years. However, no tree is immortal, and some die long before they are fully grown. According to a list made by the archeology as a result of his research, the 12 oldest trees that are still living around the world are:

Sri Lanka-Sacred Indian Fig (Jaya Sri Maha Bodhi): The tree known as the tree from which Buddha attained enlightenment is 2305 years old. It is the oldest living tree in the world known to be planted in 288 BC.

California, USA-President: The 3200 year old tree is the 3rd largest tree in the world according to the size of its trunk and is also the 5th oldest non-clonal tree. In the measurement made in 2012, its body was measured as 1,300 cubic meters.

Portugal-Oliveira do Mouchão: 3350 years old, an olive tree in Portugal and also one of the oldest trees in Europe. Despite its thousands of years of life, it still produces olives.

Chile-El Gran Abuelo: It is the oldest tree in South America and is 3622 years old. Fitzroya was named cupressoides in honor of Robert FitzRoy, captain of Charles Darwin’s ship.

Britain – Llangernyw yew Tree: It is one of the old male yew trees planted in the garden of Saint Digain Church in the village of Llangernyw. Although determining the age of yew trees is very difficult, according to a study conducted in 2002, it is thought to be between 4 thousand and 5 thousand years old.

Iran – Sarv-e Abarkuh: It is known to be at least 4000 years old as a result of estimates and is considered a monument of Iran. It also has a height of 25 meters and a diameter of 18 meters. It is an important tourism center

Turkey Zonguldak-yew wood: wood in 2016, is the oldest known exactly 4112 years old yew tree and the world. One of the good news that emerged as a result of the examinations is that the tree is still very healthy and can live for at least 4 thousand years as long as it is not harmed by humans.

White Mountains in Methuselah – California: 4845 years old. It is the second oldest known tree in this region and home to the oldest living trees in the world.

California, USA-Old Hara: It was determined to be 5067 years old and was dated by Tom Harlan in 2012. The location of the tree is kept secret to protect and unfortunately there are no photos of the tree on the internet.

Swedish-Old Tjikko Tree: It is estimated to be at least 9,558 years old and is a clonal tree, meaning it has renewed its new branches, trunk and roots over millennia.

California, USA-Jurupa Oak: It is estimated to be the oldest plant in California and the second oldest clonal plant in the world. It has survived to this day, surviving the bush fires and 13 thousand years of destruction.

USA Utah – Pando Trembling Giant: The tree identified as a single organism is a giant clonal colony of male aspen. Pando is more than 80 thousand years old, the oldest clonal tree colony in the world. At the same time, its weight is estimated at 6 million kilograms and is the world’s heaviest living organism.

In the fight for a tree’s survival, a biological addressing of the problems can be of little help. A good gardener and anyone interested in tree health can benefit from rescue techniques! There are practical tips for identifying and solving common problems.

What Are The Reasons That Make a Tree Sick?

Main Enemies of Trees

  • Environmental factors (e.g. water shortage, poor soil, excessive wind, too much or not enough sunlight)
  • Insect pests that eat or damage tissues
  • Mites, especially spider mites
  • Mushrooms attacking live trees
  • Bacteria
  • Viruses
  • Invasive species and exotic diseases
  • Some large mammals, such as bears and deer
  • People

Environmental Stresses

The resources required for the growth of a tree; sun light, water, nutrients and shelter etc. are situations. Too much or too little of these can damage trees. Sunlight is a powerful and dangerous source of power. When trees are exposed to too much sunlight, their leaves dry quickly. At the same time, UV light damages many organic substances, from plastic to human skin.

Some trees are adapted to grow in a full forest canopy (cover). Tree care professionals invest in high-cost UV protection and efficient water regulation, but they benefit from high food production. Some trees stop fighting to be the biggest and get all the sun. They sprout well in the shade, use less energy and need less food production. Shade-tolerant species are those that can thrive in the shade and in the presence of natural competition by other plants. Shade-intolerant species require full sunlight and little or no competition. Some trees that thrive without too much sun (shade tolerance) are maple, cypress, cedar, beech, chestnut and oak wood, etc.

Soil Compaction Strangulation of Roots

Highly compacted soil prevents both oxygen and water from reaching tree roots. Without oxygen, roots are much less efficient at transporting water to leaves. The roots secrete exudates containing protective antibacterial and antifungal chemicals, as well as chemicals that promote beneficial microorganisms. Beneficial organisms suffer from poor soil conditions, such as root function.

How to Understand Soil Compaction?

• If water accumulates near a tree after rainfall, it could be a bad sign. Because healthy roots use water fast and aerated soil drains quickly.

• Seedlings do not take root and the area is bare.

• A simple stick can be used to mix the soil. It usually occurs where compression is caused by pedestrian or vehicle traffic. Sometimes it seems that the top soil is fine, but the subgrade is almost useless.

Soil can be measured with the penetrometer, which is a soil hardness measurement device. In this way, healthier and more accurate information can be obtained in the evaluation.

How to Aerate the Soil Around the Tree?

Soil compaction around established trees is not easy to process, so when planting trees it is necessary to make sure that the soil has a good and open structure. Older techniques to prevent the formation of compacted soil around established trees include:

• Creating a barrier around the hull to maintain soil moisture and reduce the impact of vehicle and pedestrian traffic.

• Drilling small holes around the tree and filling them with materials that allow air and water to permeate, such as peat or porous ceramic.

• Radial trench operations that involve digging a trench around trees and backfilling it with good quality soil. This is a good exercise, but it takes time.

• New and faster treatments include the air sphere. In this process, the soil is spread and loosened by injecting air into the soil.

Moist Soils

Accumulated water for roots is worse than compacted soil. It prevents oxygen from reaching the roots, causes the growth of potentially dangerous fungi, and can produce toxic chemicals by anaerobic bacteria. If the area for the props or plantings is dug up and filled with water, it could be a sign that the garden needs some drainage. Alternatively, there are many varieties of trees that tolerate water-saturated soils. Among them are willow, ash, cedar, birch, and maple varieties.

Wind Damage

Many important trees have adapted to growing in the lowest forest levels protected from strong light and strong winds. They usually cannot survive in open or isolated situations. Examples include species such as palm trees, magnolias and rhododendrons that live especially in warm regions. Wind damage is easy to detect. Saplings or more fragile trees need to cling to stronger trees such as roses, or hills or walls if they are to survive. Supporting structures can help prevent damage.

Nutrient Deficiencies

A lack of nutrients slows the growth of trees. Trees need nutrients such as nitrogen, phosphorus, potassium, calcium, magnesium and sulfur as macronutrients. They need other elements such as iron in smaller amounts, but this is very important. For example, sweet gum trees are prone to severe leaf chlorosis (yellowing) that is iron deficient. It may cause leaf loss. The problems differ from region to region.

Insect Damages

The war between insects and trees has been going on for many years. Trees have tough defense mechanisms against insects that want to eat them or nest in their tissues. We can list some of them as follows:

  • A hard shell that is indigestible and of little value as food
  • Toxic chemicals such as nicotine, pyrethrum and neem extracts
  • Indigestible inner tissues such as lignin

But some insects persist in fighting and find paths around or into the tree’s defenses. Examples of these insects are as follows;

  • Leaf Miner leaf worms
  • Probes that attack stems or roots
  • Scanners that can completely destroy trees in extreme attacks
  • Sap suckers

Root Drill

It is not always easy to find root eaters, but the citrus root plant stands out as an adult when it feeds on the leaves of fruit trees. Yet it is the larvae (young insects) that do the main damage. An adult female worm can lay 5,000 eggs on leaves that she carefully folds to form a temporary home. When the young appear, they fall to the ground and take shelter in tree roots. If they eat the taproot, the tree may die.


Most caterpillar infestations are not harmful. Even if large numbers of caterpillars infest, they cannot seriously damage a tree, even if it occurs late in the growing season. Because the tree will already have taken many nutrients from leaves. Spring invasions can be more serious, and attacks on fruit trees are bad news for farmers.

Ways to Control Caterpillars

• Cutting off affected leaves

• Removal of caterpillars from leaves by collecting, sweeping or washing. And then through caterpillars

• If the above practices are impractical, chemical and non-chemical insecticides can be combated.

• Spraying can be done with a safe, microbial-based insecticide such as Btk (Bacillus thuringiensis courses). In addition, only caterpillars will be destroyed, excluding beneficial insects such as bees.

Leaf Miner

Leaf miner beetles nest inside a leaf, eating the inner structures but leaving the (cuticle) (outer covering) intact. Usually they leave a different pattern on the leaves. Leaf miners rarely do serious damage, but can also hinder the yield from fruit trees. It is often an annoyance that makes a tree look bad.


Assimilating insects, such as aphids, lime beetles, and mealybugs, are relatively harmless on most trees. However, they can be very ugly, and their large number can be harmful to humans. Generally, spraying soapy water is an effective solution for aphids.

Emerald Ash Drill Beetle with Body-Boring Mega Killer

This insect has killed tens of millions of ash trees in North America in recent years and is threatened by the complete extinction of almost all types of ash trees. Emerald Ash Borer larvae are large and penetrate the inner tissues of the trees, blocking the flow of water and nutrients and allowing the fungi to affect their vital roots. Quarantining sick areas and providing disease resistance are the main strategies to counter attack.


Viruses are one of the main threats to human food crops. A common viral attack symptom is yellow or very pale green. The best way to avoid virus problems is to purchase trees from reputable suppliers. If a cut is obtained from another farmer, the tree should be carefully examined. If a tree is sick, it is best to prune and burn the affected branches. In an orchard, removing the entire tree can be the best hope of preventing disease. Examples of the destruction of viruses are the potato feed virus that causes the Irish potato famine and the destruction of the cherry leaf roll virus that damages fruit trees.


Compared to viruses and fungi, bacteria are little evil creatures in the tree care world. Plum, cherry, apricot, and peach bacterial cancer is one of the few serious infections with a commercial impact. Areas of bark sometimes kill entire branches and allow fungi to form. Cutting sick branches is the standard treatment. Other infections include Crown gall, light ironing, Yellows, Burning fire.


Mites are close relatives of spiders, but they are so small that it can be difficult to see with the naked eye. Spider mites have greater visual impact and create special webs that can cover entire trees. There are many important pest species that feed on tree sap. Apple rust mites attack apple trees and sometimes pear trees in the northwestern United States. Spruce mites can destroy the appearance of spruce trees and, in severe cases, kill them.

Human-Based Threats

Unconscious pruning, root removal, soil compaction from vehicle and pedestrian traffic can all threaten trees. Sometimes the worst enemy of trees is man. Pests and diseases find it difficult to get into the nutrient-rich interior of trees. Pruning branches or removing roots without care opens a door for the invaders. To do these it is necessary to consult appropriate pruning recommendations for each species, such as the best time of the year and how to minimize damage.

Fungal Attacks on Trees

Most fungi only grow on the roots of sick trees or dead trees. Like Amarilla species (root rot-honey fungus), they can also infect living trees and cause death by causing rot in the roots of trees. But even Amarilla cannot easily attack a tree unless it is damaged in some way. [Mushroom] If any disruption to a tree’s outer defenses can be caused by insects, grazing animals, pruning people or fire, it can provide an entry point. Some fungi can attack tree roots, especially if they have been weakened by prolonged exposure to water.

Some fungi in forests are the only creatures that can digest the harder structural components of wood, such as lignin. It produces enzymes that dissolve wood and then absorb nutrients for their own development. Fungi and braces fungi often arise from trees that have been severely infected. They weaken the tree from the inside out, but it is the mass of tube-like fungal growths inside the tree that hurt.

Dutch Elm Disease

Dutch elm disease was first detected in the Netherlands in 1921. It has since killed millions of trees in Europe, 25 million in the UK alone. About 75 percent of North American elms have also died. Bark boring beetles carry fungi from sick larch to other larches, and these fungi kill trees. There are ways to protect important elm trees with chemical and biological factors, but the main effort to reduce elm fall is focused on cutting down infested trees and breeding disease-resistant varieties.

Invasive Species and Exotic Diseases

Emerald Ash Borer and Dutch Elm Disease, described above, are examples of the threat exotic diseases pose to trees. In the natural world, parasites and diseases are in a constant struggle to overcome the defenses of their host. They develop ways or die to develop resistance strategies. When a disease or pest arrives from another part of the world, there is no time to develop a defense against this disease, equipped with strategies the tree has never encountered before.

Both the Dutch elm disease and the Emerald Ash Borer are an Asian disease and have been transported to other countries by people in commercial timber shipments. Chestnut Blight, another invader, nearly destroyed the once American chestnut tree in large areas. Pumpkin disease (Butternut Canker) has damaged northern forests.

In other cases, the invasive species may be a tree reaching an unfamiliar location and cannot cross native species as they have no natural enemies such as insects or fungi. In the UK, Sycamore, a native of central, eastern and southern Europe, has managed to capture a vast forest area, suppress native trees that are part of a vast network of habitats, and reduce bird and mammal diversity.


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