Lichen growth on apple plants is a common problem found in many orchards, especially in hilly and high-rainfall regions. Lichens are a combination of algae and fungi living together on the bark of trees. They form green, grey, or yellowish patches on branches and trunks. Many farmers worry when they see these patches, thinking it is a serious disease harming the plant. However, lichens do not directly suck plant nutrients or damage the tree tissues. The real issue is that they usually grow on weak and old branches, where the plant’s growth is already poor. So, the presence of lichens is a sign that the plant is under stress and needs better care.
Why Do Lichens Grow on Apple Trees?
Lichens grow well in conditions where there is moisture, shade, and slow-growing branches. If an apple orchard is not pruned regularly, sunlight and air circulation reduce inside the canopy. This creates a humid environment where lichens thrive. Also, trees that lack proper nutrition or are affected by pests and diseases tend to have weak branches, making them more prone to lichen growth.
Effects of Lichen on Apple Plants
Although lichens do not directly harm the plant, they can cover the bark surface and reduce its breathing ability. Heavy lichen growth may also hide early signs of diseases or insect infestation. When they appear in large amounts on branches, it means the branch is not active and needs attention.
Methods to Control Lichen in Apple Orchards
1. Regular Pruning
Proper pruning is the most effective way to control lichens. Remove dry, old, and weak branches to improve air and light penetration inside the canopy. Pruning should be done during the dormant season. After pruning, apply wound paste on cut areas to prevent infections.
2. Improve Air Circulation and Sunlight
Apple plants need open and airy conditions. By maintaining the correct spacing between trees and removing unwanted branches, you make the orchard environment less favorable for lichens.
3. Nutrient Management
Weak trees are more prone to lichen growth. Apply well-balanced manure and fertilizers based on soil testing. Adding farmyard manure and compost improves soil health and encourages healthy new branch growth, which naturally reduces lichen formation.
4. Physical Removal
In case of heavy lichen growth, gently scrape them from the bark using a soft brush. This should be done carefully so that the bark is not damaged. This method works best after rains when lichens are soft.
5. Chemical Control
Copper-based sprays, such as copper oxychloride or Bordeaux mixture, can help reduce lichen growth when applied during the dormant stage. These sprays should be used only after pruning and cleaning of branches. Spraying should be done according to recommended doses to avoid any harm to the tree.
Conclusion
Controlling lichen in apple plants is more about improving the overall health of the orchard rather than treating the lichen itself. Proper pruning, good sunlight, balanced nutrition, and good orchard hygiene are key. When trees are healthy and growing vigorously, lichens naturally reduce. With regular care, farmers can maintain clean, healthy, and productive apple orchards.
