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  • Writer's pictureCare For My Tree

Unveiling the Mystery: The Green Growth on Trees and Rocks

Updated: Jul 12, 2023

Your yard is filled with various shades of green, from the lush lawns to the vibrant leaves, and even the creeping vines and vegetable gardens.

Surprisingly, even tree trunks and branches can display a touch of green when covered in lichen or moss.

Although green spots on tree bark may seem concerning, let's delve into the true story behind the presence of moss or lichen on trees

So, what sets moss and lichen apart? Firstly, they are distinct organisms that differ in appearance and texture.

Moss is a flowerless plant that exhibits a dark green color and has a coarse texture.

On the other hand, lichen is a symbiotic partnership between fungi and algae. It can appear in various colors, including blue-green and gray, and typically grows in thin, flaky patches.

Moreover, moss and lichen have different preferences when it comes to their growing spots. Moss is commonly found on tree trunks and occasionally on rocks. Lichen, however, can cling to almost any surface, such as trees, other wood, rocks, cement, or metal.

What leads to the growth of moss and lichen? Just like any other plant, moss thrives in shady and moist areas, taking advantage of favorable environmental conditions.

Lichens also thrive where the conditions are suitable for their growth. They thrive in moist environments and require some sunlight. Consequently, they tend to cling to tree trunks in areas with dampness and partial sunlight.

Does lichen indicate tree health issues? While lichen can grow on healthy trees, it is more commonly found on unhealthy ones. This is because stressed or declining trees often have a thin canopy, which allows more light to reach the tree trunk—creating the ideal conditions for lichen growth.

But here's the truth—lichen does not harm your tree's health. It may seem like lichen is causing harm because it coincides with your tree's decline, but in reality, lichen is simply an opportunistic organism that thrives on available surfaces. If you have concerns about your tree's health, it is advisable to consult a professional arborist.

Now, let's address the question of how to remove lichen from trees. Remember, lichen is harmless to trees, so there is no real need to eliminate it. However, if you perceive lichen as an unwanted green fungus on trees, you can use a copper-sulfate fungicide to eliminate it. Additionally, maintaining proper tree pruning and ensuring good tree health can discourage future lichen growth.

Speaking of cleaning trees, some people wonder if they can use a pressure washer to remove lichen. It is best to avoid using this powerful tool on trees, as it can cause damage. Now that we've covered lichen removal, let's explore the benefits of moss and lichen.

Contrary to expectations, these green growths offer advantages. They serve as a food source for many animals and provide nesting material for birds.

For you, lichen can serve as an indicator of a stressed tree. Its presence may alert you to the fact that your tree is struggling, enabling you to take action and provide assistance to your plant.



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