Apple trees are a common sight across gardens, orchards and farms, but one of the biggest challenges for apple growers worldwide is controlling the Sanjo scale in these trees. Sanjo scales not only cause damage to the trees, but also end up ruining the quality of the fruit, making them tiny or rendering them unmarketable. In this article, we will discuss how to manage this pest and ensure that your apple trees continue to thrive.
Identification of the Sanjo Scale
The Sanjo scale is a tiny, flattened, oval-shaped insect that is about 2.5 mm in length and has a yellow-brown, tan or light brown color. They are commonly found on the bark of the tree, but can also be found on the leaves and apple fruit. If you observe an unexplained decline in apple tree health and reduced fruit production, you may have a Sanjo scale infestation. Checking the undersides of apple leaves and examining the fruit will help you confirm this suspicion.
Controlling Sanjo Scale in Apple Trees
1. Prune the Trees
Pruning of Apple trees during winter helps in removing the egg masses that usually are found under the bark, which reduce the severity of the infestation the following season. However, be sure to avoid unnecessary pruning during the growing season as this could lead to secondary infestations from insects attracted to the freshly cut branches.
2. Provide Proper Nutrition
A healthy tree is less prone to infestation, so make sure to keep your apple trees well-fed and watered. Use of organic fertilizers that contain nitrogen, potassium and phosphorus helps keep the tree healthy. It is also important to ensure adequate water supply to the tree since a water-stressed tree is more vulnerable to insect and disease attack.
3. Remove the Infested Branches
Once you identify the infected branches, prune and remove them immediately, preferably before the larvae hatch. The easiest way to kill any eggs or larvae on the pruned limbs is to soak them in a bucket of soapy water and then dispose of them.
4. Use Natural Predators
Encouraging natural predators like ladybugs and lacewings in your orchard can help control Sanjo scale and reduce their population. You can promote the presence of these insects by planting flowers like yarrow, dill, coriander, or clover around your apple trees.
5. Apply Horticultural Oil
Horticultural oil suffocates the scale and makes it easier for predators to get at them. Spray the oil on the tree trunk, branches, leaves and fruit during the dormant period before the buds start to grow, as this will reduce the risk of damaging the tree. Be sure to follow the instructions on the packaging and dosage as applying too much horticultural oil can harm the tree.
In conclusion, controlling the Sanjo scale in apple trees requires proactive measures to maintain tree health and reduce the population of these pests. Pruning, providing proper nutrition, natural predators approach, and the use of horticultural oil are ways apple growers can keep this pest under control. By applying these methods, you can keep your apple trees free from infestation and ensure a bountiful harvest of high-quality fruit.