Interview: All about frosts in Peru.
Engineer William Carrasco Chilón, National Research Director of the National Institute of Agrarian Innovation (INIA) of Cajamarca, was interviewed to explain to us about frosts, focusing on the national consequences of this phenomenon.
What is frost?
Frost is a meteorological phenomenon that consists of sudden temperature drops to 0ºC or less. This decrease in temperature causes physiological damage in crops that locate mostly in flat areas than in hillside areas.
Which crops are most affected during the frost season in Cajamarca?
The most affected crops in Cajamarca, considering the order (of importance), are corn, pea, alfalfa, potato and cereals such as barley, wheat and oats.
Which areas are mainly affected by frosts in Cajamarca?
In general terms, at 2400 meters above sea level (m.a.s.l) the average temperature is 15ºC; therefore, there is not much presence of frosts. On the other hand, at
2600 – 2800 m.a.s.l, including Cajamarca (2750 m.a.s.l), the average temperature is 12ºC and sometimes it decreases to 0ºC early in the morning, so there is a higher incidence of frost. In the case of areas located at 3000 - 3800 m.a.s.l, the average temperature is 8ºC and can drop to -10ºC, which implies a higher presence of frosts. However, the presence of frosts increases considerably at 4000 m.a.s.l, where the average temperature is 6ºC and the lowest can be -17ºC. This data indicates that at higher altitudes there is a higher incidence of severe frosts.
Speaking specifically of Cajamarca, some of the most affected areas are: La Encañada, Porcón, the province of Chota, the district of Chunmal and some localized areas of Cutervo.
In what seasons do frosts occur in Cajamarca and areas of Lima?
In Cajamarca, frosts last approximately three months. They occur in May, June and during early July, although sometimes it extends until the first half of July.
Regarding the coast, like Lima, there is not much incidence of frosts but of mist, so there is a greater predominance of fungal diseases. This is because the mist increases relative humidity, which allows the pathogen to cause infection.
How do frosts affect production of crops in Cajamarca?
Frosts directly cause loss in crop production, which affects the plant according to its growth phase.
In extreme cases, there may be a loss of up to 100% of the product if frosts affect the plant during the fertilization phase and the beginning of flowering. As a consequence, the economic loss would also be 100%. When this happens, the farmer doesn´t use his crops as an alternative for his consumption, instead he starts consuming supplies that he normally doesn´t produce, such as noodles, rice, canned products, etc.
If frost affects the crop in the early phase of grain filling, some seeds will die while others will only shrink, leading to considerable product and economic losses of 40-60%. On the other hand, once there is a fully formed grain, frosts can decrease productivity by 20-30% due to the weight loss of these grains. However, frosts no longer affect crops at all when there´s already a dry gain that reached physiological maturity.
How does INIA or farmers prevent frosts from causing a major impact on crops?
First, farmers receive technical advice from INIA professionals regarding the most favorable sowing time during the year. For that reason, farmers do not sow during seasons where frosts may occur (May, June, July). In this way, they prevent a complete loss of their products if the early growth phases of their crops are exposed to this phenomenon.
Second, farmers ensure that their crops meet all their nutritional requirements in order to withstand the considerably low temperatures.
In hillside areas, farmers install plantations of considerable size (“live fences”) on the perimeter of their properties. In this way, the crops are protected from the effects of frosts. In addition, farmers generally have a small area of land and they schedule the sowing season of their self-consumption crops to avoid any effect of frosts.
We thank engeneer William Carrasco for the time provided. Email: email@example.com