Mango, the “king of fruits,” is one of India’s most cherished crops. It provides good income to farmers, but its success depends on healthy trees and clean fruits. One of the major hidden enemies of mango orchards is the scale insect, a pest that slowly weakens trees, spoils leaves, twigs, and even fruits if not controlled in time. Effective management of scales is essential for long-term orchard health and productivity.
1. What are scale insects?
Scale insects are tiny, sap-sucking pests that attach themselves firmly to the plant surface. They are usually found on the undersides of leaves, twigs, and branches. Because of their small size and protective waxy covering, they often go unnoticed until the damage becomes visible. They come in different forms — soft scales and hard scales — and both types feed on the plant’s sap, weakening it over time.
Adult females look like small, oval or round brownish or gray bumps on the bark or leaves. They do not move, while the young stages (called “crawlers”) spread to new parts of the tree. As they feed, they excrete a sticky substance called honeydew, which encourages the growth of black “sooty mold” on leaves and fruits.
2. Damage symptoms
When scale populations increase, the following signs appear:
Yellowing or curling of leaves
Sticky surfaces on leaves and fruits
Presence of black sooty mold (looks like black dust)
Drying of young shoots and branches
Poor flowering and reduced fruit size
If not managed, heavy infestations can even lead to branch dieback and reduced yield in the following season.
3. Factors favoring infestation
Scales thrive under dry weather conditions and in orchards with poor air circulation or dense canopies. Overuse of nitrogen fertilizer and irregular pruning also encourage scale buildup. Lack of natural predators such as ladybird beetles can make the problem worse.
4. Integrated management practices
To manage scales effectively, farmers should adopt a combination of cultural, biological, and chemical measures.
a) Cultural control
Prune regularly: Remove crowded or infested branches after harvest to improve air movement and light penetration.
Destroy infested twigs: Burn or bury heavily infected plant parts to prevent spread.
Maintain orchard cleanliness: Keep weeds and ant colonies under control, as ants protect scales from their natural enemies.
Avoid excessive nitrogen: Balanced fertilizer use helps maintain healthy trees less prone to pest attack.
b) Biological control
Encourage beneficial insects such as ladybird beetles, parasitic wasps, and lacewings. These natural predators feed on scales and help keep their population in check. Avoid unnecessary pesticide sprays that harm these friendly insects.
c) Chemical control
When infestation is severe, use targeted sprays. Apply horticultural or neem oil (2%) during the dormant stage or just before flowering to suffocate the scales and eggs. For heavy attacks, insecticides like dimethoate or imidacloprid (as recommended by local agricultural authorities) can be used carefully. Always spray in the early morning or evening, covering both upper and lower surfaces of leaves.
5. Post-treatment care
After control measures, monitor the orchard every two weeks. Remove dried or infested twigs and maintain proper irrigation. Encourage tree health through balanced fertilization and periodic pruning.
Conclusion
Scales in mango may look small, but their damage can be serious if ignored. With timely pruning, orchard hygiene, use of neem oil or recommended insecticides, and encouragement of natural predators, farmers can easily keep this pest under control. A clean, well-managed orchard not only produces more fruits but also ensures better fruit shine and market value year after year.
