Hello. From the attached pictures it is not possible to accurately identify the strange deposits, but it is possible that they are aphid eggs. In this case, considering the period in which we are, it is recommended to carry out the treatments that are specific for the dormancy period (after the leaf fall) with horticultural oil: . The package contains 1 sachet of Mospilan 20 SG + Toil adjuvant, which have to be diluted in 10 L water. The treatments should be applied on dry bark, not covered by ice, snow or frost, on days with positive temperatures, preferably minimum 5-6 °C. More information on these treatments can be found in our article: Winter treatments with oils and copper-based products.
Additionally, also during this period, it is recommended to use a fertilizer with a high potassium content which increases the resistance to drought and frost and improves the water balance of fruit trees, such as: . It is administered by spreading it around the plants in a dose of 30-50 g/m², followed by gentle incorporation and watering, according to the recommendations on the label.
From spring onwards, for disease and pest control, you can consider carrying out preventive treatments throughout the entire growth period.