Avocado Tree Diagnosis
Avocado tree problems can range from cosmetic to life-threatening. An unhealthy tree will lack vigor, may decline in health, and can ultimately die. Common culprits for an ailing tree are pests, fungal diseases, poor soil, and improper care. Treating the wrong underlying cause can lead to even more serious problems. Diagnosing the cause of the issues is the first step towards helping the tree recover.
Pest Problems
The most typical pest problems with avocados are due to mites, scales, beetles, or borers, as well as small rodents or birds. Pest infestations in trees may be evidenced by leaves or branches that appear to be wilting, discolored, yellow, defoliated, or have dark patches. There may also be sticky bugs or droppings on the leaves and bark, or the bark itself may appear damaged or chewed. If possible, bring a sample of the pest to an extension or pest specialist for an identification and treatment advice.
Fungal Diseases
Fungal diseases are some of the most common causes of death in peach and apricot trees. Common avocado tree disorders caused by fungi are canker, root and crown rot, shot hole, and anthracnose. These conditions are mostly evident in the form of discolored leaves, wilting, yellow spots, and brown streaks on the bark. In order to identify the fungal disease, a sample of the infected part should be taken to a local extension or plant diagnostic laboratory.
Soil Issues
A tree may display signs of ill health if it’s not in the right type of soil. It should be planted in a well-draining soil mix with a pH between 6.0 and 7.0. A soil test can determine if the pH and nutrient levels are adequate. Soil can become compacted or nutrient-deficient, and may also become saturated due to a poorly draining field or pooling water. A good soil environment is essential for a healthy tree.
Improper Care
Tree health can be adversely affected by improper planting, pruning, watering, fertilizing, or pest and disease management. The wrong type of pruning or fertilizer can cause yellowing of the leaves and bark, or cause the tree to become infected by pests and diseases. If not properly cared for, an avocado tree can become stressed and susceptible to further damage.
An Avocado Tree in Health
An avocado tree in health will have vigorous growth, dark green leaves and branches that are straight and upright. The bark should be free of discoloration, blisters, and signs of disease. A healthy tree is mainly pest- and disease-free, and should fruit regularly.
Possible Solutions
For the individual whose avocado tree is not in health, there are often solutions to the problem. If the soil is not of the correct pH or nutrient levels, then a soil amendment or fertilizer may be used. Proper pruning techniques can also be used to improve a tree’s health and provide good fruit production. Different pest controls may also be needed, depending on the type of pest. Fungal diseases can often be treated with fungicides or pruning techniques.
Preventative Measures
The best way to keep an avocado tree healthy and pest- and disease-free is by providing the right environment and conditions. Plant in well-draining soil and in a place that receives sufficient sunlight. Avoid planting in areas with puddling water, or too close to other trees. Prune properly by removing dead or diseased branches, and by avoiding removing all of the leaves. Properly water, fertilizer, and pest management measures should also be employed.
Grafting
One way to help an ailing avocado tree be more productive is by grafting. Grafting involves joining a scion (bud wood) from a desired variety of avocado tree onto the rootstock of another tree. The scion will take root and the grafted tree will produce fruit of that variety. There are both advantages and disadvantages to grafting, so it should be done properly and with caution.
Healthy Growing Environment
Creating a healthy environment for the tree’s growth is key to having a robust tree. Avoid overcrowding avocado trees, allow for good airflow, and avoid over-watering. If the tree is in a pot, it should be checked regularly for roots that have outgrown the pot, and be moved to a larger pot to encourage healthy root growth.
Diagnosing Avocado Tree Issues
It can be difficult to diagnose the exact cause of stress or disease in a tree. While home diagnosis is possible, it is recommended to seek professional advice if you are unable to identify the problem. A certified arborist or an extension specialist can provide a reliable diagnosis and treatment options.
