Almonds have been blooming in Israel for thousands of years, but the climate crisis could affect traditional cultivation. A special interview in honor of Tu B'Shvat with Dr. Or Sferling
By Tomer Atir, Angle - Science and Environment News Agency
Although blossoming is one of the symbols of spring in Israel, even now, in the height of winter, you can find almond orchards in their peak glory. On the occasion of Tu B'Shvat, we conducted a special interview with Dr. Or Sheflerling, an almond tree researcher from the Agricultural Research Administration - Volcanic Institute. Sheflerling, who is this year in the almond growing powerhouse of California, talks about the aspiration for sustainable agriculture, the uniqueness of dry habitats, and the impact of the climate crisis on almond trees, in Israel and abroad.
What is it about the almond tree that made you want to research it?
"Almond is an amazing tree and I love it very much. It is a very old plant in Israel, and following 5,000–6,000 years of almond cultivation in the Land of Israel, we have every fungus, disease or virus of the tree. In contrast, in California, the almond growing industry grew 70 years ago, and now it dominates the world market with 90 percent of production. The environment in new areas is less damaging to the plantation, so the crops tend to be more productive in suitable areas – but where there were no almond trees historically. This is a crop that yields huge amounts of money, and which has brought venture capital funds to invest in agricultural companies in California."
In early February, the Water Authority announced that this was the driest winter in 100 years. How is the almond tree responding to this?
"Almond blossoms are supposed to happen towards the end of winter, around March. In relatively warm winters – like this year – The trees tend to bloom earlier."And indeed we see that the flowering has already begun in early February. This is a problem because the almond flower is delicate and it needs pleasant weather. The weather also needs to allow bees to graze and pollinate almonds. Rain, hail or a cold night can severely damage almond trees that are blooming because the flowers are very delicate. Therefore, in 'normal' winters they bloom when the weather moderates."
"In agriculture, we deal with the survival mechanism of crops. If the weather is not optimal in the winter, then towards the summer the trees will avoid heavy harvests after warm, dry winters so as not to die. In other words, their natural tendency is not to produce much fruit this winter."
"Usually, when we talk about the climate crisis, we focus on warming, but if we're honest, there's not enough rain. The change in precipitation is greater than the change in temperature, and agricultural research needs to learn how to compensate for the missing rain."
You are involved in sustainable agriculture, how do you define this concept?
"sustainable agriculture It is agriculture that can be sustained for a very long time. The condition for its long-term existence is proper and non-harmful management of resources – such as the environment, and my research deals with intensive but responsible management of the means of production. For example, almond farming in California is a huge industry and there are huge plantations there that bring in a lot of money. But communities will not agree to the existence of the plantations if they dry up their water sources, as is happening today. Basing almond farming on environmentalism and profitability will enable large-scale production over time. This is a different emphasis on sustainability compared to the organic direction that is usually talked about."
Sounds complicated. How do you increase the intensity and also protect the environment?
"My lab's specialization is twofold. On the one hand, we come from the field of agronomy, with researchers who grew up in the world of agriculture and understand the industry itself. On the other hand, we focus on data science; we collect a lot of information and invest most of our time in writing code to analyze the information. Familiarity with crops and the agricultural environment produces a wide variety of tools."
"I'll give you an example from the world of irrigation: irrigation pipes can burst as a result of pressure or become clogged as a result of poor water quality. This creates a situation of environmental stress, because at the height of the season the water will not reach all the trees. Such a problem opens up two directions of research. The first is to develop statistical models for identifying faults in irrigation systems in very large areas – a single orchard can be the size of a neighborhood or a community settlement. The second direction is to test how long the trees can remain unharmed if such a fault occurs. In other words, how long does the farmer have to find and fix the fault before irreversible damage is caused to the trees? A day or a week? In such a case, it is possible to identify in satellite images the development of herbaceous vegetation that has grown in the area of the leak, or to use pressure sensors in the pipeline that indicate where the pressure has dropped."
And where does the water for irrigation come from?
"Dry areas can be very fertile and important [from an agricultural point of view], for example Australia, Israel, southern Europe and California. Agriculture needs flat spaces, light soil and a lot of sun. Agriculture also needs water and minerals. Therefore, dry plains that are close to mountains excel in agriculture."
He said that rain and snow fall on the mountain and flow down into the valley. "You can see this in Israel - in the Hula Valley and the Jezreel Valley, and on a larger scale - in the Po Valley in northern Italy and in the Alps. In the United States, there is the Central Valley of California, which is twice the size of Israel. To the east of the valley are the Sierra [Nevada] Mountains, 650 kilometers long with peaks 4,400 meters high. They absorb huge amounts of water that flow into the dry valley and make it the most agriculturally fertile place in the world."
Sounds like a good natural solution. What do you do in dry agricultural areas that don't have water flowing from the mountains?
"Large quantities of water need to be transported to such areas – if not naturally, then through plants like the national carrier in Israel or the dam system in California. Beyond the challenge of transporting the water, there is the challenge of the salts that come with the water. In hot areas, the water evaporates, the salt remains and damages the soil and crops."
What other challenges do almond growers face?
"The fertilization of the almond tree requires two different varieties that bloom at the same time. In a year like this, the varieties don't bloom together, the bees don't make the necessary visits, and the fruits don't develop. This increases the tree's chances of surviving a cold winter, but it's a blow to farmers."
How do you solve this?
The most limiting factor is the need for two almond varieties to bloom at the same time regardless of the weather. A workaround is an almond variety that does not need another variety for fertilization. This is not science fiction – almonds are a relative of the peach, and peaches do not need cross-fertilization (the transfer of pollen from a flower of one tree to a flower of another tree, TA). In fact, almonds that do not need external fertilization are already being grown in Spain. In Israel, the Agricultural Research Administration, led by Dr. Doron Holland, developed an independent almond called Matan, but it is a slightly different almond. In a huge mechanized industry, whose produce is intended for snacks, milk and protein substitutes, a 'slightly different' almond is not good enough. It takes a long time to determine whether new varieties satisfy farmers and consumers."
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