So, I’m here in Morocco to learn about citrus…life, culture, and anything else that might be useful to Placer/Nevada growers. What have I learned so far?In a long discussion with one of my Moroccan colleagues at IAV (the Ag & Vet Institute), we came to the conclusion that a culture survives and prospers because it is tolerant. Morocco and Moroccans are very tolerant…we might learn something from them about that. When we want to find a plant that will succeed in certain conditions, you expose it to whatever it is susceptible to…disease, conditions, etc. - the strong ones have or develop tolerance. I think it’s the same for human beings, so we need to get to know people whose culture or religion is different than ours, so we develop tolerance too.
Last week, I spent some time reading the first volume of a French manual on Mediterranean citrus production – the Arboriculture volume. What I learned is: Everyone classifies citrus differently. The Citrus family is complicated because of its tendency to hybridize, but...!! The two taxonomists that have had the most impact on citrus were at the two ends of the spectrum: Swingle who minimized the number of species, while Tanaka divided everything up (into over 160 species!).
As always with classifications, there are lumpers and splitters…the author of the French citrus manual, a certain Monsieur R. Loussert, is a splitter, Since his manual is generally used in this part of the world, people here follow the same idea. According to M. Loussert, mandarins are divided into:
· Citrus unshiu, Satsuma mandarins;
· Citrus deliciosa: common or Mediterranean mandarins, traditionally are large trees, with seedy but tasty fruits that used to be common in this part of the world. Willowleaf mandarins seem to be mostly under common or Mediterranean mandarins (but they are not always grouped together either!), but are C. reticulata or C. deliciosa, or both, depending on who is doing the listing.
· Citrus clementina: Clémentines: includes Nules and Algerians, as well as most of the cultivars grown here…Oro Grande, Bruno, Carte Noir, Sidi Aïssa, Nour, etc.
· Citrus reticulata which seems to include pretty much everything else, including a broad range of hybrids, e.g. tangors.…Murcotts, Nova, Ortanique, Pixie, Tango. Also W. Murcott Afourer, which is known here as Afourer (ah-foor-rare), after the family whose farm it came from. It is a proprietary variety with royalties not only on the plants, but on the yield as well!!
On the other hand, in Dr. Othmani’s lab, next to where I am sitting,, there is a a very nice citrus poster from a German fruit export company. It calls all mandarins Citrus reticulata, and Satsumas are C. reticulata var. unshiu. It has one that it calls Citrus reticulata var. tangerina…which doesn’t look much different than the others it lists as mandarins. It's the first time I've seen the word tangerine in any language except English! The word tangerine doesn’t exist in French or Arabic. And the poster does not separate Clémentines from other mandarins. Clearly, there is no a standard system.
I tend to be a lumper and want to put them all under C. reticulata. I'd rather just call them all mandarins, which seems to be the overwhelming opinion in the greater citrus world. Here people are really clear that Clémentines, including Algerians, are mandarins.
I would like to understand these classifications better…why people divide them up, are there are actually important differences? I like things to be organized! Given the complexity and the fact that in the States we often use a hybrid version of the two classification systems, I may not get to the clarity I’d like!
From farm visits, I’ve learned that we should take a look at some of the certification norms (EuroGAP, etc.) for export that the Moroccan farms follow…it may be helpful when food safety legislation starts coming down. They have very specific requirements for signage for informing workers and visitors to farms, about where to find things on the farm, hand washing, drinking water, eating areas, and they place highly visible trash cans on posts throughout the orchard. 
They seem to have many of the same posting requirements about pesticides and other hazards. Christine Turner would be happy about that! Some really good practices, but a few that we might not want to follow. More on that later.
One of the ideas that Dr. El Othmani is trying to test is the idea of planting the orchard rows on raised beds/bunds…It might have value in some situations in colder areas or areas with shallow soil. I’d like to see the comparison between planting on the flat and on raised beds. Those of you who have seen Rich Johansen’s orchard know he has trees planted on raised beds. It gives you more soil for the roots to mine for water and nutrients. It will keep the roots warmer and get growth going earlier in the spring in a wet year. However, the ridges will also dry out faster in summer and weed management, if you are not using herbicide, is much more difficult.
As far as cultural practices: irrigation: they have converted many previously flood irrigated orchards to drip with few negative impacts. However, their drip is not always what we would call low volume. Locally manufactured drip hose has emitters that range from 4L per hour (+/- 1 gal/hr to 40 L/hour – 10 gallons per hour). The upper range isn’t low volume by my standards! In French & Arabic it’s called goutte à goutte - drop by drop. 10 gal/hour is a lot of drops!
Water management is as critical to their future as it is to ours. Most of the farms on drip also fertigate, and have pretty impressive containment systems to be sure that fertilizers, etc. do not get into the water source or leak out from the fertigation systems. One I’ve visited is all computerized.
As far as nutrient programs…they also divide their fertilizer into at least 3 applications…many more if they are fertigating. Their general nitrogen recommendations for lighter soils…i.e. those of you with DG…are to put out ⅓ to ½ of the annual amount in February-March. A more accurate timing equivalent is about one month before flowering. So, more like March for us, as we are still getting a lot of rain in February, and it often doesn’t start warming up until March. Then, in April/May, another ¼ to ⅓, then in June, the final ¼ to ⅓. They don’t apply N fertilizers after June, which is a good recommendation. For us, it could stretch to early July at the latest, given our season starts a little later.
In some places they also intercrop alfalfa...this is a new planting of citrus, which has been almost swallowed up by the alfalfa. Intercropping may not be a bad idea, butg it really requires careful management...and too much N from the alfalfa the first years may not be the best for the tree.
Pest management. They have CA Red scale here – they call it “Californie”, the French word for California! Many release Aphytis wasps for it…the bigger orchards have their own insectaries.
Mediterranean Fruit Fly - Medfly is a huge problem for them. Because they export to the US, they have to be very careful about Medfly. They make straw traps with spinosad baits or sometimes permethrin. It takes a lot of vigilance and sometimes a number of sprays to keep the fly under control, though. They also do a cold treatment during the shipping process to meet US standards.
Here's a picture of the farm office at Melk Lotfi, one of the small COPAG (the ag cooperative) farms. The son of the owner is really into technology, and uses spreadsheets to manage the nutrient and pest management programs. He receives weather and evapo-transipration information from a nearby weather station on his cell phone each day, which he then uses to schedule his irrigations. Check out the farm map on the wall as well. (click on the picture to make it bigger) Pretty slick…
More on mandarins after I visit another orchard.
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