Photo by Giuseppe Biondino

In the last few days, sev­eral European coun­tries were struck by an extra­or­di­nary wave of cold which low­ered tem­per­a­tures below freez­ing. Cities like Rome and Naples were blan­keted in snow and, while author­i­ties and civil pro­tec­tion were han­dling the spe­cial event with the nec­es­sary pre­cau­tions, many took advan­tage of this to take a break and wage snow­ball fights in an unusual land­scape.

Growers who had already pruned should beware, as the intense cold of the last few days was not that favor­able to prun­ing wounds, espe­cially in the case of reform oper­a­tions.- Nicolangelo Marsicani

The weather front also called the ‘Beast from the East,’ in Italy was dubbed ‘Burian,’ from the Russian word Buran (буран), which is the name of the glacial air flow orig­i­nat­ing in the region of Siberia that gave rise to the cold snap. Many see the extreme weather event as a con­se­quence of cli­mate change, but among mete­o­rol­o­gists, most con­sider this as an ordi­nary con­tin­gency.

Photo by Giuseppe Palestini

“This wave of cold is part of a series of nor­mal cyclic events which occur dur­ing win­ter,” said Massimiliano Morucci, an Italian mete­o­rol­o­gist spe­cial­ized in mid- to long-term Forecasts. “This kind of cold spells hap­pen every 8 or 10 years, occa­sion­ally every 6 years. This time, the Burian hit Italy and other Central and Southern European coun­tries more intensely than usual because it reached very low tem­per­a­tures at the level of European Russia,” Morucci explained.

“In my opin­ion, we can­not define this par­tic­u­lar event as a cli­mate change con­se­quence. In any case, we still can­not deter­mine whether cli­mate change is lead­ing us to such an impor­tant mete­o­ro­log­i­cal vari­a­tion.” In sub­stance, what hap­pened would have been caused by a colder flow, due to a nor­mal Siberian depres­sion which always occurs dur­ing this period but now went well beyond the clas­si­cal lat­i­tudes.

Coldiretti, in a pre­lim­i­nary assess­ment of frost dam­ages to agri­cul­ture in Italy, reported losses in crops such as let­tuce, cab­bage, chicory, broc­coli, potato and arti­choke, and indi­rect dis­rup­tions caused by traf­fic restric­tions that hin­der deliv­er­ies.

Photo by Giuseppe Biondino

Farmers are wor­ried about fruit plants like apri­cot, cherry, peach and pear trees since in some areas buds already devel­oped and these are par­tic­u­larly cold-sen­si­tive. The fine weather of pre­vi­ous weeks had, in fact, stim­u­lated veg­e­ta­tive growth in sev­eral regions and now pro­longed tem­per­a­tures below zero are seen has a threat for crops.

Early last year, Mediterranean coun­tries were affected by a sim­i­lar drop in tem­per­a­ture that first caused con­cern and then turned out to have ben­e­fi­cial effects on olive trees.

It is worth recall­ing that cold can affect the wood of olive tree if the min­i­mum tem­per­a­tures drop below ‑7°C (19.4°F) for 8 – 10 days, and seri­ous harm can be caused to the canopy and trunk if they fall below ‑10/-12°C (14/10.4°F) in a few hours.

The hope is that, again this year, low tem­per­a­tures can bring mainly ben­e­fits to the work of olive grow­ers, help­ing them in reduc­ing the olive fruit fly pop­u­la­tion and con­tain­ing fun­gal dis­eases.

“This wave of bad weather does not seem to have dam­aged olive trees in our area,” observed Nicolangelo Marsicani, who pro­duces an award-win­ning extra vir­gin olive oil in Sicilì, in the heart of the Cilento, Vallo di Diano and Alburni National Park. “Here olive trees were still in veg­e­ta­tive rest and low tem­per­a­tures surely helped to con­tain the onset of pests.”



There are many vari­ables, but we can say that com­pli­ca­tions could arise if and where the veg­e­ta­tive growth of olive trees, before the win­ter rest, was already active. In this case, dam­ages will soon be vis­i­ble, as liq­uids like water and lymph can freeze if exposed to low tem­per­a­tures for too long.

“Growers who had already pruned should beware, as the intense cold of the last few days was not that favor­able to prun­ing wounds, espe­cially in the case of reform oper­a­tions,” our farmer added. “Anyway, we have to wait a few weeks to see if plants have been harmed.”

At the moment, some farm­ers reported injuries like branch break­ages on young plants, which are del­i­cate and unpre­pared to bear the weight of the snow, but also on more robust olive trees. Too much snow can, in fact, over­bur­den the sec­ondary branches and cause frac­tures, which, in addi­tion to the imme­di­ate loss, could facil­i­tate the pen­e­tra­tion of olive knot bac­te­ria in more sus­cep­ti­ble vari­eties, Marsicani noted.

On the pos­i­tive side, when it comes to snow, the expan­sion of water upon freez­ing turns out to be use­ful as it causes micro­c­racks in the soil just like a nat­ural tillage. Moreover, if frost lasts for sev­eral days, this will pro­vide a good water reserve, extremely use­ful against sum­mer heat.

Experts remind us that oper­a­tions in the olive groves should be sus­pended until the ground and the veg­e­ta­tion will be dry again and ready to receive the appro­pri­ate prac­tices.




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