How to treat tree lichen

Should You Remove Lichen from Trees? (& Other Questions) • Rayzor's Edge Tree Service

We often get calls from customers about lichen on their trees, with questions about why lichen grows on trees, whether it’s harmful, if lichen means the tree is dying, how to remove lichen, and more. In this FAQ article, we answer the most common questions about lichen in Connecticut.

Have you ever marveled at those wrinkly, platy, fibrous, or brightly colored patches growing on your trees? Have you wondered what they are and if they’re hurting the tree?

You’re probably looking at lichen; one of nature’s most interesting creations. Read on to learn what it is and what it is (and isn’t) doing to your trees.

What is lichen?

Lichen is a living organism that is part fungus and part algae. These two components live in a mutualistic relationship, meaning that each benefits the other. The algae photosynthesize and the fungi provide anchoring filaments for the algae and collect and hold moisture.

Working together, these two components of lichen can survive in a range of environments, from coastal sea level to the arctic.

Is lichen a type of moss?

Although it is often confused with it, lichen isn’t a moss. Mosses are in a different family of primitive plants and have leaf, stem, and root-like parts. You’ll often find mosses and lichen growing near each other, which can lead to confusion.

One big difference is that lichen prefers full sun to grow, while mosses prefer more shade.

Where does lichen grow?

In short: lichen grows almost anywhere. If there’s sunlight and moisture, lichens will grow.

Unlike green plants with leaves, roots, and flowers that grow and are pollinated in ways that we’re familiar with, lichen is only a surface-living organism. It draws its growing requirements from the algae it grows with and from the atmosphere around it, not through roots.

This is why you’ll find lichen growing on rocks, roofs, gravestones, metal gates, glass, soil surfaces, and, of course, trees.

Does lichen grow in Connecticut?

There are tens of thousands of types of lichen found all over the world. Depending on their type, they may be yellow, orange, green, or gray, and may resemble foliage, hairs, or a powdery or crusty surface.

In Connecticut alone, there are hundreds of species of lichen that you’ll find all around the state. They’re found on forest trees, boulders left behind by glaciers, and on the state’s ubiquitous stone walls built by farmers after they harvested the rocks from their fields. The state’s oldest lichens (the ones that grew on the primeval forest trees that once covered Connecticut) are long gone, along with the trees themselves, but there are plenty more all around you.

How does lichen survive?

As long as the fungi and the algae that makeup lichen can draw moisture from the atmosphere and have enough sunlight to photosynthesize, lichen will survive. There’s no need to water or feed it; lichen can get everything it needs from its immediate environment.

Because of this epiphytic behavior, it can seem like lichen grow from nothing, in thin air. Of course, anyone who’s grown an epiphytic “air plant” knows that they need nutrients and water too, not just air – and it’s the same for lichen.

Can lichen survive a drought?

Lichens aren’t able to store or conserve water so they will dry out during periods of drought. However, this doesn’t mean they’re dead!

When conditions improve, lichens will quickly absorb any available moisture, including rain, dew, and even water vapor, such as fog. They’ll even absorb moisture from the air itself if it’s very humid.

Once they’ve absorbed enough water, they’ll start photosynthesizing and growing again.

How does lichen spread?

Most lichens spread by growing across the surface of whatever they’re living on.

When they dry out, pieces of lichen often break off. These small crumbs can be blown to new locations by wind or carried by animals. If they land in a hospitable location, they’ll start growing whenever they receive enough moisture.

Will lichen hurt my trees?

No, lichen will not hurt your trees. Because of their structure and growth habit, lichen will grow on your tree but not into your tree. A tree’s bark is just a useful surface for lichen to attach to.

Because lichen has filaments that anchor it to a surface but no roots that take up water or nutrients, there are no connections from the lichen to your tree’s vascular system or energy stores.

Does lichen grow mostly on unhealthy trees?

Lichen will grow on both healthy, vigorous trees and on older or declining trees.

The health of a tree is not related to the appearance of lichen, although many people think lichens damage trees and associate lichen growth with a stressed or declining tree.

A tree’s bark is simply an ideal location for lichen because it provides everything lichen needs to grow:

  • Sunlight
  • Moisture
  • A surface to attach to

So why do we see more lichen on declining trees?

An older, declining tree may have a sparser crown or leaf and branch dieback, which means an increase in sunlight that reaches branch and trunk bark where lichen grows. Rainfall and atmospheric moisture will also more easily reach the tree’s branches and trunk when they are not intercepted by leaves. These conditions will naturally increase the growth of lichen, as it’s a beneficial setup.

An older tree may also have more brittle and fissured bark which offers more places for lichen to attach to. Plus, an old tree may have stopped exfoliating its bark. Exfoliation is a natural process for many trees and a way that lichen is dislodged from a younger tree’s surface.

Another thing to remember is the slow rate at which lichen grows. It may take years of your tree’s life before lichen becomes extensive enough to be really noticeable.

No matter the age or health of your trees, the growth of lichen indicates that the air is clean (it won’t grow in polluted conditions) and moisture is available. So you shouldn’t automatically associate the appearance of lichen with negative factors affecting your trees.

Should I remove lichen from my trees?

Again, it’s a no. There’s no reason to remove lichen from your trees– except for cosmetic reasons. Lichen isn’t harming it and, more importantly for your trees, removing it may cause permanent damage to your tree.

If I want to remove lichen, how should I do it?

A tree’s bark is a sealed, waterproof layer of protection. Any activity that damages or removes bark can affect the tree’s health by allowing pests or diseases to get inside. So don’t use steel brushes, chisels, or any heavy tool to remove lichen.

If you absolutely must remove lichen, spray your branches with a gentle soapy solution. After wetting the lichen, you can use a natural-bristle scrub brush and gently exfoliate the lichen off. Don’t scrub hard, especially on young, thin bark. You can wash off the residue with a stream of water from your garden hose.

If your tree is in good health, you can prune off branches that have more lichen than is to your liking. But, in general, don’t prune if there’s not a solid reason for it, particularly during the active season of insect pests and diseases that can attack your tree.

Learn more about types of pruning for your trees

What else can I do about lichen in my tree?

If you think your tree has lichen because of its poor health, the best approach is to improve your tree’s health. This could include:

  • adding compost around your tree,
  • using a foliar fertilizing spray,
  • ensuring your tree has enough irrigation, and
  • treating any other diseases that might be present on your tree.

Since lichens need a lot of sunlight to thrive, a full-leafed and shady tree crown may be the best revenge.

See how trees in Connecticut benefit from supplemental fertilization

Are there any benefits to lichen?

While we can’t speak for its internal life, lichen does serve many external purposes.

In addition to it being an indicator of healthy air quality, lichen is a food source: animals, including squirrels and voles, will eat it; deer will gnaw at it in the winter, and some indigenous tribes in what is now New England would eat it as well when food was scarce. Birds include lichen as nest-building insulation.

NOTE: Some species are not edible and can be poisonous, so don’t just peel off a length of the first lichen you see and toss it in your mouth!

There is also a long history of humans using lichen. For centuries, lichens have been used for textile dyes. In the U.S. and Finland, lichen was used for its antimicrobial compounds to treat wounds and even athlete’s foot. These same extracts from lichen that have anti-bacterial properties are found today in toothpaste and deodorants. You may have lichen on you right now!

Want to learn more?

Below are two excellent sources of information about lichen in Connecticut.

  • The University of Connecticut’s Home and Garden center
  • Connecticut Botanical Society’s Facebook page has photos of lichen

Give Us a Call

We’re here to help if you have questions or aren’t sure if you’re looking at lichen or something else on your trees. If your trees are declining, it’s not because of lichen. However, we can evaluate and diagnose what is going on and give you a comprehensive treatment plan.

Tree Lichens: How to Get Rid of Lichen on Trees

Shades of green can be spotted all around your yard; from lawns to leaves, to vines or vegetable gardens.

While tree trunks and branches aren’t typically a place you expect to see green, that’s exactly what happens when lichen or moss crops up.

You might assume green spots on tree bark are a sign of trouble, but below, let’s get into the real story behind moss or lichen on trees.

What’s the difference between moss and lichen?

A couple of things. For starters, they’re not the same organism. And, they look and feel quite different.

Moss is:

  • A flowerless plant
  • Dark green in color
  • Coarse to the touch


  • Is a partnership between fungi and algae
  • Comes in a variety of colors (blue-green, gray and more)
  • Grows in as thin, flaky patches

Lastly, moss and lichen prefer different growing spots. You’ll likely only find moss on tree trunks and maybe rocks. But lichen will latch on to nearly any surface, including trees, other wood, rocks, cement or metal.

What causes moss and lichen?

Just like any other plant, moss will grow if the environment is right. It thrives in shady, moist areas.

Lichens also sprout wherever the conditions are in their favor. They love moisture, and they need light to thrive, so they’ll cling to tree trunks in areas with dampness and some sunlight.

Does lichen grow on healthy trees?

It does, but it’s much more common for lichen to appear on unhealthy trees. The reason being, trees that are stressed or declining usually have a thin canopy. Fewer leaves and branches mean more light shining on the tree trunk, and again, that’s precisely what lichen needs to grow.

Is lichen harmful to my trees?

Ok, moment of truth: does lichen kill trees? Nope! Lichen does not pose a threat to your tree’s health.

Sometimes it appears that lichen is hurting your tree because it grows at the same time your tree is declining. But the reality is, lichen is an opportunistic organism just looking for a surface to grow on, and unhealthy trees happen to be a good option. So, no need to worry about lichen harming your tree, but you should reach out to a professional arborist if you have other concerns about tree health.

How to get rid of lichen on trees

To reiterate, lichen is completely harmless to trees, and there’s no real need to get rid of it. But some people don’t view lichen as one of “nature’s wonders,” and instead consider it a green fungus on trees.

If that’s the case for you, you can use a copper-sulfate fungicide to kill lichen. Then, discourage future growth by keeping your tree properly pruned and in good health.

One question Davey arborists sometimes get is: can I use a pressure washer to clean or spray trees and get rid of lichen? It’s best to not use this powerful tool on trees. Here’s why.

Benefits of moss and lichen

Why yes, believe it or not, these green growths come with perks. Both are used as food for many animals, and as nesting for birds.

What’s the benefit for you? Well, since lichen seeks out stressed trees, it might be the reason you discover your tree is struggling. With that, you can take action to help your plant, thanks to lichen.

Read here for more on tree bark “fungus” identification.


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Pityriasis versicolor: symptoms, causes, treatment



Alina Rashidovna

Experience 9 years

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Pityriasis versicolor is an infectious dermatological disease that affects the upper layers of the skin. It is not very dangerous, and is not contagious and does not give serious complications. It also has other names - colored or multi-colored lichen.


Common symptoms of pityriasis versicolor, which do not depend on the form of the disease, look like this:

  • Scarlet asymmetrical spots located on the back, shoulders, abdomen, head and neck. The sizes of the spots are different, they can capture quite large areas of the skin.
  • Brown or yellow spots, also varying in size, with jagged edges, often merging into larger formations.
  • Severe desquamation of tissues in affected areas.
  • Itching sensation. But it is important to know that it does not always occur - only in cases where pityriasis versicolor is accompanied by a secondary infection.
  • Lack of sunburn on painful areas of the body. This is due to the fact that the fungus that affects the skin disrupts the work of melanocytes.

There are other symptoms of pityriasis versicolor - they are associated with a specific form:

  • Follicular. Most often associated with discomfort and suggests the presence of sores, various papules and rashes.
  • Inverted. With this form, the spots are in the folds of the skin - armpits, in the groin area.
  • Erythematosquamous. This form is characterized by light spots without signs of inflammation. Most often, formations are observed on the back, abdomen and chest. Children can develop such pityriasis versicolor on the head.

Since many people do not have symptoms of the disease, they may not pay attention to this disease for years. As a result, it becomes chronic: periodically disappears, then, under the influence of negative factors, it is activated again.

Important! If signs of pityriasis versicolor appeared in a woman during pregnancy, this does not pose any danger to the baby. But you can not start treatment before childbirth, since pills that treat diseases are just undesirable for the development of the fetus.


Pityriasis versicolor in children occurs only if personal hygiene is not observed or skin care is incorrect. As a rule, up to 10 years the body itself is able to cope with pathogenic organisms, if the barrier functions of the skin are not violated. But after the age of ten, hormonal changes begin, due to which susceptibility to pathogenic fungi grows as a result of various negative factors - children can get sick on a par with adults.

The course of the disease does not depend on age - both in small patients and in large ones it is the same.


Most often, the disease occurs in people from 10 to 60 years. As a rule, it does not cause severe discomfort, but is associated only with negative aesthetic consequences. After the age of 60, such age-related changes in the skin occur, due to which it becomes less susceptible to the causative agent of the disease.


The causes of pityriasis versicolor are the same bacteria and fungi that live on our skin and are considered part of its normal microflora. However, under the influence of various negative factors, the fungus can acquire pathogenic properties. These factors include the following:

  • Increased sweating. In another way, it is called hyperhidrosis.
  • Disturbances in the work of the sebaceous glands.
  • Severe and regular overheating - being in hot rooms, wearing too warm clothes.
  • Changes in the composition of sweat, which may be associated with diseases, taking certain medications.
  • Various diseases of the internal organs, including autoimmune diseases.
  • Hormonal surges during pregnancy, medication, menopause.
  • Poor quality synthetic clothing.
  • High acidity of the skin.

The development of pityriasis versicolor most often occurs against the background of reduced immunity, so there is some pattern regarding the time of its appearance. Most often, people face such a problem in the autumn-spring period, when there are not enough vitamins, sunlight and physical activity.


Since there are quite similar problems, the diagnosis of pityriasis versicolor is carried out not only at the examination level, but also using special tests:

  • microscopic examination of the scraping;
  • Balser test with iodine;
  • Wood's lamp transillumination;
  • "Bernier's symptom" analysis (exfoliation of the skin).

For a complete picture, the patient is assigned general blood and urine tests.


For the treatment of pityriasis versicolor, tablets are used (immunomodulators and antifungal agents, vitamins), as well as topical ointments. In some cases, antifungal shampoos are prescribed. If the patient has a sensation of itching, he is prescribed antihistamines.

Now in pharmacies there are a lot of products intended for the treatment of pityriasis versicolor, but it is important to understand that they all require individual selection. In no case do not self-medicate - it will either not give an effect, or it will only delay the inevitable trip to the dermatologist. It is better to make an appointment with a specialist at JSC "Medicina" - dermatologists with extensive experience work in our clinic in Moscow. They will quickly make an accurate diagnosis and select an effective treatment regimen for you.

As for alternative methods, it is recommended to discuss them with your doctor. As a rule, when using modern and effective means, they are useless, and therefore simply waste the time and effort of patients.


Now the prevention of pityriasis versicolor is relevant for all people. It includes the following recommendations:

  • Fight hyperhidrosis (excessive sweating) - take a shower more often, put on clean clothes, use additional products: deodorants, special creams, powders.
  • Dress appropriately for the weather and avoid overheating in all situations.
  • Do not injure the skin with too frequent washing, regular use of ordinary soaps, scrubs, peels.
  • Observe the rules of personal hygiene - including not using other people's hygiene products.
  • Wear comfortable, breathable clothing, preferably made from natural fabrics, especially close-fitting clothing.
  • Maintain immunity: lead a healthy lifestyle, give up bad habits, eat right. After consultation with an endocrinologist, many people are recommended to take additional vitamin complexes.
  • Take care of your health: stop acute conditions in time, treat chronic diseases.
  • Use cosmetics wisely - they should suit your skin type and your needs. If it is difficult to understand the compositions of numerous products, it makes sense to go for a consultation with a cosmetologist and choose the care for the skin of the face, body and head individually.

There is nothing specific in the prevention of pityriasis versicolor - it implies a responsible attitude to one's health, which is necessary for every person and in any situation.


Is pityriasis versicolor transmitted from person to person?

The disease is not transmitted by household or other means, so that the patient does not need isolation.

What causes pityriasis versicolor?

The reason is that fungi and bacteria, which are normally found on our skin, become pathological when the immune system is weakened. That is, anyone can face such a problem.

How to treat pityriasis versicolor?

Pityriasis versicolor on the head is treated with special ointments, shampoos and tablets. All the same applies to other localizations, only shampoo is not used. Folk methods are not suitable for these purposes - only special medicines, selected individually by a dermatologist.

Pityriasis versicolor - treatment, symptoms, photo

Pityriasis versicolor, also called multi-colored, is a fungal pathology that affects the upper layers of the epidermis. There is an opinion that residents of countries with a hot climate suffer from this disease much more often. But the Russians are also becoming victims of this extremely unpleasant disease. The number of infections increases markedly during the summer months. Most of the patients are young boys and teenagers.

The main problem is related to the duration of therapy, which can last up to several months and even years. This is due to the propensity of the pathogen to numerous relapses. Despite the fact that the disease does not limit a person’s working capacity, it can cause great psychological discomfort. Therefore, if multi-colored lichen occurs, treatment should be carried out as soon as possible.

Turning to a highly qualified and experienced dermatologist will shorten the treatment period. Such a specialist can be found at the Yuzhny Medical Center. By making an appointment at any convenient time, you can undergo a diagnosis and receive competent recommendations regarding the treatment of the disease, as well as its prevention.

Pityriasis versicolor - what is it?

The disease is a superficial lesion of the skin, which is provoked by a yeast-like fungus of the genus Malassezia.

The mentioned pathogens are representatives of the typical microflora of the skin and are normally present on the skin of many people, while not causing any ailments. But under the influence of external or internal aspects, these microorganisms pass from a non-pathogenic to a pathogenic form. As a result, the fungus penetrates into the upper skin layers, where it affects melanocytes. The latter are the cellular structures that are responsible for skin pigmentation.

These processes become the reason why light or dark pink spots appear on the skin, which peel off in the middle. When touched, scabs peel off, which look like flakes. It was this feature that caused the pathology to be called pityriasis versicolor.


In addition to external defects, the disease does not have any effect on the functioning of the body as a whole and the functioning of its individual organs, and does not entail any physical restrictions. However, the unaesthetic appearance that the skin acquires due to the development of pathology can cause a decrease in self-esteem, psychological discomfort and tightness of a person. How the skin of a patient with pityriasis versicolor looks like can be seen in the pictures below.

Lichen versicolor species

Modern doctors talk about the existence of several forms of pathology:

  1. Achromatic - flowing without pronounced pigmentation.
  2. Hyperpigmented - the development of which leads to the appearance of dark spots on the skin of the patient.
  3. Follicular - characterized by small round spots located around the hair.

Causes in humans

The role of the main provocateur of the appearance and development of pathology is the reproduction of its pathogens on human skin. These are the yeast-like fungi Malassezia or Pityrosporum. The following factors can become the cause of the pathological process:

  1. Immune deficiency and disruption of the endocrine system.
  2. Acute stage of chronic inflammatory diseases of the gastrointestinal tract, hearing organs, throat, etc.
  3. High activity of the sebaceous glands.
  4. Increased sweating.
  5. Hormonal failure.
  6. Extended exposure to high humidity environment.
  7. Influence of UV rays.
  8. Frequent application of aggressive agents or antibacterial gels to the skin that violates its protective barrier.

In addition, local or general protective forces can be weakened under the influence of other factors:

  1. Poor diet.
  2. Surgical interventions
  3. Severe forms of infectious diseases.

Sometimes the disease occurs against the background of pregnancy or therapy of malignant tumors. May also occur as a result of prolonged use of adrenal hormones. If we are talking about children, then in this case, multi-colored lichen most often occurs due to the frequent application of fat or oil to the skin.

It often happens that the disease affects several relatives at once. Factors that contribute to the emergence of a family form of pathology are the similar composition of sweat and skin type.

Symptoms of pityriasis versicolor

As a rule, the very first signs of the disease are single rashes that appear on the human body. Outwardly, these are rounded spots with a diameter of 2 to 10 centimeters, having a pink color and darker edges.

As the pathology progresses, individual rashes become larger in size and eventually merge with each other, forming large areas with scalloped edges. The color of the spots varies from pink-red to a darker red-brown. The spots begin to gradually spread to other areas of the patient's body. Sometimes the pathology affects the scalp, hips and armpits. Rare cases of spots on the face.

Over time, bran-like scales appear on the surface of the rashes, which are almost invisible outwardly. However, when scraped, they are easily separated. On the skin there are both old and newly appeared rashes.

As a rule, the disease does not cause pain and physical discomfort, proceeds without inflammation. However, approximately 50% of patients experience itching and hyperhidrosis.

If the pathological process affects the skin of the head, then the disease can go unnoticed for a long time, because the hair is not damaged and does not fall out. The disease is characterized by a tendency to a chronic course.

Diagnostics in the Yuzhny center

You can identify lichen in a timely manner by contacting the Yuzhny medical center. Experienced and competent dermatovenereologists provide services here, who will conduct a competent examination, using all the necessary examination tools, in order to make an accurate diagnosis. In the vast majority of cases, the disease can be diagnosed using the Balzer iodine test. Its essence is reduced to intensive staining of infectious foci using a 2% iodine solution.

In modern medicine, Wood's lamp is also widely used as a diagnostic tool used to detect lichen versicolor. This device emits long-wavelength ultraviolet rays. A specialist using a magnifying lens carefully examines the skin illuminated by a lamp. Unaffected areas show a light blue color when exposed to UV rays, while diseased areas differ from them in color under the lamp. It is a certain color that allows the doctor to draw a conclusion about the type of skin disease that occurs in each case.

Treatment of pityriasis versicolor

Pathology therapy involves taking antifungal drugs, which are prescribed by the attending physician based on the clinical picture and the results of the diagnosis. Medicines contribute to the destruction of pathogens and stop their reproduction on the surface of the epidermis. External agents are indicated for a small area affected by the disease. When pityriasis versicolor is detected, treatment involves the use of medicines for internal administration, if the rash has spread widely enough, and local remedies do not show effectiveness.

In the process of therapy, experts advise spending more time in the sun and sunbathing. Exposure to sunlight allows you to get rid of the coarsened fungus and help speed up the treatment. Only white spots remain on the skin, called pseudoleukoderma. They can be easily removed by exposure to UV radiation.

During treatment, it is important to change clothes and underwear frequently, as well as to boil them for at least 20 minutes. This is necessary to exclude the presence of the causative agent of the pathological process on them.

Treatment of multi-colored lichen with drugs is prescribed exclusively by a qualified doctor. Self-medication is unacceptable. In order to shorten the time to fight the disease and avoid unwanted complications, it is recommended to contact the Yuzhny clinic at the first manifestations of the disease.

Review of effective drugs

A wide variety of antifungal drugs are available today. This allows you to choose the right form, and eliminate addiction. Among the most effective drugs:

  1. Lamisil spray is easy to apply to the skin. It is prescribed for extensive lesions of the skin with rashes. Has a low risk of side effects.
  2. Clitromazol, available as an ointment or cream. Active components destroy the causative agent of the disease, suppressing the production of ergosterol in it. Possible side effects.
  3. Mycorozal is an ointment, the effect of which appears quite quickly. But it is important to complete the course of treatment to the end. Contraindications - the period of pregnancy and lactation.


As you know, the development of any disease is easier to avoid than to treat it. The same expression is relevant for pityriasis versicolor. To reduce the risk of pathology, you must adhere to the following preventive rules:

  • minimizing stress;
  • a healthy diet that can prevent hypovitaminosis;
  • timely treatment of chronic diseases of internal organs;
  • the use of clothing made from natural materials and the rejection of fabrics that provoke irritation of the skin;
  • combating hyperhidrosis by wiping the skin with a solution of water and salicylic alcohol, maintaining personal hygiene, etc.

You can prevent the development of lichen on vacation by avoiding being in direct sunlight immediately after swimming. You should wait until the skin dries up, and only then sunbathe. It is better to refuse visits to spontaneous beaches, the use of other people's towels and other items. You should definitely take a shower after swimming in the pool or visiting the beach.

It is known that the fungus remains in dust particles, on clothes and other things for quite a long time. In order to prevent the recurrence of the disease, all items should be disinfected using chlorine. Iron linen and clothes with a hot iron.

Can children have pityriasis versicolor?

The disease affects not only adults, but also children. It occurs in a child due to the reproduction of yeast-like fungi, which are part of the microflora of the skin. This reproduction takes place under the influence of changes in the activity of the glands of the skin and the general weakness of the body resulting from: