The palms They bring distinction and exoticism to gardens and parks, but they are exposed to pests, diseases and physiopathies These can compromise their growth and even lead to death if not detected and treated promptly. Knowledge of the main threats, early recognition of symptoms, and the implementation of appropriate strategies are key to the conservation and health of these magnificent species.
Main agents affecting palm trees
Palm trees can experience problems caused by three main reasons:
- Pests: Among which insects, mites and beetles stand out.
- Diseases: Produced mainly by fungi, bacteria and viruses.
- Physiopathies: Disorders resulting from adverse environmental conditions, nutritional deficiencies and/or poor cultivation practices.
Most common physiopathies of palm trees
- Salinity damage: Exposure to salty sea air can dry out the leaves and even kill the palm tree if the species is not adapted.
- Root asphyxia: Excess water, poor aeration, or poorly draining soil can cause root rot and plant weakening.
- Sunburn: Plants accustomed to shade that are suddenly exposed to direct sunlight may suffer and show burns on their foliage.
- Herbicide toxicity: Various herbicides can cause deformity, root necrosis, and leaf damage. Recovery can take months.
- Water stress: Lack of water manifests itself in reduced growth and necrosis at the leaf tips.
Main pests and symptoms in palm trees
No pest is more dangerous for a palm tree than one that affects its heart, the only point of growth. The destruction of the bud usually means the death of the plant.
- Red Spider (Tetranychus urticae): It thrives in dry air. Damage appears as pits and webs on the underside. Maintaining humidity and applying specific acaricides helps control them.
- White Spider (Polyphagotarsonemus latus): Less common, it attacks tender leaves. The use of acaricides is essential.
- Mealybugs (various species): They are found on the veins and undersides of leaves, causing yellow spots and promoting the development of fungi such as sooty mold. Manual control and the application of rotating anticoccidial products are recommended.
- Red palm scale (Phoenicococcus marlatti): Protected from light at the base of the leaves, it rarely kills the plant but can severely weaken it. Pruning and destroying affected leaves, along with phytosanitary treatments, is recommended.
- Drill (Opogona sacchari): A butterfly that lays its eggs in crevices; its larvae excavate galleries in the trunk, filled with excrement. Systemic insecticides are the most effective remedy.
- Black Donut or Brown Lizard (Spodoptera littoralis): Its larvae emerge from the soil and damage young leaves. Treatment with systemic insecticides is essential.
- Red Palm Weevil (Rhynchophorus ferrugineus): The worst enemy of palm trees. Its larvae bore into the bud and roots, causing weakening and eventual death. The cycle is rapid, and the attack may not be detected until it's too late. Integrated control, including preventive spraying and removal of severely affected specimens, is necessary.
- Palm weevil (Diocalandra frumenti): Similar to the red palm weevil, but slower-acting, it kills the palm tree if not treated with appropriate products.
- Coccotrypes dactyliperda: It damages the seeds by using them as a shelter, making the plant's reproduction difficult.
- Daisy flower (Pentodon punctatus): A beetle that attacks the roots and base of palm trees, requiring specific treatments and manual removal of larvae from the soil.
- Apate monachus: Larvae that burrow into leaf veins; control involves removing and burning affected areas.
- Thrips: Visible damage to leaves, which turns silvery. Control by removing weeds and treating the undersides of leaves.
- Mythimna joannisi: Nursery defoliator difficult to control except by removing infected material.
Most common diseases in palm trees
Diseases can affect roots, trunks, and leaves, and tend to progress gradually but irreversibly if not treated promptly.
- Anthracnose (Colletotrichum): The appearance of dark brown, blackish, or oily necrotic spots. It primarily affects young leaves. Treatment with specific fungicides and the removal of severely damaged leaves is essential.
- Fusarium wilt (Fusarium oxysporum): A soil-borne fungus that grows through broken or injured roots, causing desiccation and leaf discoloration. Root health, avoiding excessive watering, and applying chemical defense only in the initial stages are essential.
- False rust (Graphiola phoenicis): It causes yellow to brown warty spots and pustules with premature defoliation. Increasing aeration and using fungicides such as mancozeb help mitigate its spread.
- Gums: Formation of gummy exudates on the trunk and branches, a symptom of stress or fungal attack. It is essential to improve drainage and ventilation, in addition to pruning affected areas.
- Phytophthora palmivora: It causes root rot and leaf drop in very humid environments or after transplanting. It is important to treat with specific products applied during irrigation to avoid root damage.
- Viral and bacterial diseases: Lethal yellowing and that caused by Xylella fastidiosa They cause a collapse of the vascular system and the gradual disappearance of the leaf crown.
Prevention and recommendations for keeping palm trees healthy
- Planting in well-drained and well-aerated soils to minimize the risk of rot.
- Frequent and controlled watering, avoiding both prolonged drought and excessive humidity.
- Pruning leaves and infected parts in winter and immediate treatment of wounds with insecticides or fungicides.
- Acquisition of plants with a phytosanitary passport to prevent the introduction of exotic pests.
- Monthly monitoring of symptoms and presence of insects, applying treatments as soon as anomalies are detected.
- Rotation of phytosanitary products and a combination of preventive and biological strategies to avoid resistance.
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Complete guide to choosing the best pot for palm trees: tips, materials, and species
If you have palm trees affected by pests or diseases, consulting a plant health specialist can save valuable specimens and prevent the spread to other plants. Integrated management and early care are the best way to maintain the health and beauty of palm trees in any green space.