Damage caused by extreme weather conditions

DAMAGE CAUSED BY EXTREME WEATHER CONDITIONS

Conditions: Early spring frost, hail, waterlogging

DESCRIPTION

Hazelnut production is particularly dependent on environmental and climate conditions. The most significant cultivating areas are usually near large water reservoirs like Black and Mediterranean Sea and Pacific Ocean.

EARLY SPRING FROST might interrupt pollination, damage current season’ shoots, leaves, pollinized female clusters and young branches. Orchards laying on high elevations (500 m a.s.l) are often affected. Serious crop loss might happen when the temperature drops below 0°C in March or April. Influencing the yield, heavy frost events condition prices and export.

The 1st picture is the phenological stage of the hazelnut that might be affected by the early spring frost and on the 2nd bud that is already affected and might be damaged with the ice ©nhgardensolutions.wordpress.com

HAIL DAMAGE can occur at any point during the growing season and make an impact. When the hail storm happens early in the growing season, the damage and consequences are much higher. Hailstone size and intensity will also determine how much damage the fruits receive.

PEST & DISEASE RISK – Hail damage such as branch breaking, wounds on stems and twigs might open the space for pathogens.

At severe hail storm events: • • Trees can be stripped of leaves and fruit Leaves can be bruised, torn and with holes

Hail storm damage on hazel trunk and brunches ©Agriser

WATERLOGGING – There are a number of consequences resulting from constant water accumulation in the orchards. For the hazelnut trees waterlogging is considered as a condition of a plant stress. When the soil is saturated with water, the air in the soil pores is displaced with water. Due to lack of aeration the oxygen supply to the roots is prevented. Prolonged waterlogging can cause alteration of soil acidity and accumulation of toxic products for the roots. Symptoms of waterlogging stress include wilting and chlorosis of leaves due to lack of nitrogen and shoot dieback.

Disease risk– Apart from damaging the root system due to lack of aeration, diseases are favored by wet and humid conditions. Therefore, when the soil is waterlogged the humidity will be much higher contributing to increasing disease pressure.

MEANS OF CONTROL

Management of hail damaged hazel trees:

• • • • Inspect the damage of hazel trees as soon as possible after the hail event Pruning of damaged plant parts after the hail storm Hail wounds on the trees and bark may need a fungicide to prevent pest and disease entry Where practical, large wounds on trunks and branches should be covered with a water-based paint to avoid desiccation and disease infection

Management of waterlogging in the orchard:

• • The best proven strategy is to drain or pump water from the orchard within 48 hours For the large surfaces spoon drain dug can facilitate water movement

Kopanje drenažnih kanala

Damage caused by hail in hazelnut orchard goes to a much less extent compared to apples, pears, and fruits with a soft flesh.