To end the topic of fieldwork that José Manuel started in the previous post and which we showed in chapter 16, I am going to tell you about what happened to me when I decided to stop doing any fieldwork in my family’s centenary vines. I am talking circa 1997 and 1998. I had just finished my degree in agricultural engineering and I also stopped cycling at a professional level, which I had been practicing for 6 years, so I returned with bundles of energy to take care of the family vineyard. We have a few hectares in a square layout, planted at 1.6x 1.6. We had been working them with a mule up to 1995, which was when “Macho Rubio – Blonde Male” died – the last mule my father had to work the vineyard. It was a sad day, although it was old. We then worked the vineyards with my uncle’s small articulating tractor, as a large one would not enter. I actually despised this tractor, because it was dangerous and it was nothing compared to Macho Rubio. Therefore, we only worked the vineyard with this tractor for a couple of years until one day I told my father that we were not going to work it any more. It sounded so sacrilegious that my father almost chucked me out of home, but a few years later, it proved to be a good idea and the vineyard even improved in spite of having centenary vines. So, now I can say our family vineyard, which is planted in a square layout, has not been worked in 14 years; meanwhile though, we have been maintaining the soil using other systems.
I have to recognize that during the first years of cultivation vines may need some support. It is then when fieldwork can be more crucial. I am talking about the first 5 or 6 years, which is when the vine’s rooting system develops fastest and fieldwork can be carried out to facilitate their implantation. Despite all this, we can see how Francesc Capafons, in vineyards on hillsides with poor and craggy land, is growing vines not only without carrying out any fieldwork but in full competition with weeds (which he says are not bad for the vine at all, in fact they are very positive). Therefore, the thought that fieldwork is essential to grow a vine is not so clear anymore.
Once the vineyards ‘s first years have passed, fieldwork seems to be even less necessary, up to the point where I believe that it is the worst way to maintain soil, regardless of the advantages it may provide.
After weighing the pros and cons of fieldwork, I choose no fieldwork, mainly because:
1 When fieldwork is carried out and the soil is too fresh (something very typical in spring), compaction is produced just below the worked and loosened soil and a hard and waterproof layer is produced called tillage pan.
2 Erosion is favoured, especially in vineyards with inclination – and there are many. In some cases, it can be dramatic; in an 80-year-old vineyard, for example, you can see how a few centimetres of land have been dragged due to run-off and the farming implement.
3 Sometimes infertile soil horizons are brought out (changing what nature has taken several eras to form).
4 We break superficial roots and sometimes whole trunks and vines.
5 We spend more time and gas (higher cost and greater carbon footprint).
6 In spring, the risk of frosts rises.
7 After it rains, accessing the plot is more complicated because of the mud (take into consideration that accessing the vineyard is sometimes necessary because a treatment has to be applied or the grape has to be picked).
Therefore, as fieldwork is not indispensable we can manage without it (if possible and they allow you).
And if we do not carry out any field work, which is the best system?
Well, clearly, if the weather and irrigation system allows it, the best system is growing vegetation covers, because it is ecological, it avoids erosion, it provides organic matter, it avoids compaction, and you can access the plot earlier after it has rained.
Only when competition for water is excessive, do we have to start thinking about eliminating the weeds. In our conditions, in La Rioja and most of the areas in Spain, the best system may be a mixed system, a vegetation cover until May or June and then the use of a herbicide as less aggressive as possible to eliminate this cover – continuously cutting it or even using sheep, as we already explained in chapter 5.
Soil maintenance is one of the most important operations carried out in a vineyard and for this reason, we want to dedicate an entire chapter to covering the different techniques used. However, we would also like to expand on some specific aspects, and therefore we are going to dedicate the topic a couple of posts which we think will leave no questions unanswered. Firstly, I am going to talk about the advantages and disadvantages of carrying out fieldwork and not carrying it out, and then Raúl is going to give his own opinion and tell us an interesting personal experience. Let’s start:
When we carry out soil maintenance work, we aim for several objectives:
• The main objective is to create a favourable environment from a physical, chemical and biological point of view for the vine’s root system to develop.
• Another important objective is to control the presence or absence of species that compete with the vines for water and nutrients.
• It will also simplify the access of personnel and machinery and other several operations such as pre-pruning, pruning, debudding, the protection of crops, etc.
There are different strategies involved in the soil maintenance of a vineyard. The most traditional strategy is fieldwork. By means of fieldwork, we turn over the soil in order to, amongst other things and as we will see below, eliminate the spontaneous vegetation that grows in the vineyard’s lanes.
Traditionally, due to the strong resistance of vines, that is, their capacity to adapt to soils and drought, they were cultivated in non-irrigated areas, often in plots where other crops could not be grown. As a result, the most extended technique when working soil in vineyards was fieldwork. This was because maintaining the soil free of other species that compete for water in non-irrigated areas was essential for the vines.
However, due to the evolution of winegrowing, of the legislation (irrigation was not allowed in the past), the colonization of new plots, the increasing availability of water for cultivating, the search for higher-quality grapes and wines, the need to control the vine’s vigour and the need to control erosion issues arising from vineyards with an inclination, amongst other things, has led to the use of vegetation covers in vineyard’s lanes, that is, between the rows of vines.
The most extended soil maintenance techniques are currently:
-SOIL WITH FIELDWORK: free of vegetation during the entire year.
-SOIL WITH A VEGETATION COVER:
-Temporary or during the entire vegetative cycle
-On the entire surface or on part of it only
-Natural vegetation (local) or seeding.
However, there are other soil maintenance techniques such as Mulching, which consists in covering the surface of the vineyard with lifeless materials (vegetable residue, straw, plastic, etc.), but which is currently only carried out in the lanes in order to keep them free from vegetation and avoid the use of herbicides.
Amongst the advantages of fieldwork we can list:
With regard to the soil’s properties:
• It regulates the hydrological regime.
• It aerates the soil.
• It buries amendments and fertilizers.
• It mobilises mineral elements.
• It eliminates the soil crust and loosens up the compacted soil.
With regard to the vine’s development:
• The destruction of the superficial root system favours the deep penetration of roots.
• It eliminates weeds by burying them or cutting them.
• It buries mildew inoculum and reduces the capacity for infection.
With regard to the soil’s biological properties:
• It favours aeration and microbial activity in the soil.
• It eliminates, although temporarily, weeds.
• It eliminates plants that act as plague reservoirs.
However, it also has some disadvantages:
With regard to the soil’s properties:
• If not worked when in suitable conditions: Tillage pan
• The farming implements can bring out an infertile soil horizon.
• By loosening the soil, erosion is favoured.
With regard to the vine’s development:
• Mutilation of the superficial root system.
• Wounds are inflicted on the trunk where wood diseases can penetrate.
• An increase in the risk of spring frosts and coulure if fieldwork is carried out in a sensitive period.
With regard to the control of weeds:
• Fieldwork breaks weeds and thus disseminates the seeds: little persistence in their control.
• When working the soil, pieces of plants multiply fast and they are dragged towards the front.
With regard to the vegetation covers, there are also advantages:
• Nitrogen sets in the soil.
• Protection against soil erosion.
• Provides organic matter to the soil.
• Controls weeds.
• Reduces the loss of water in the soil due to evaporation.
• Improves the soil’s structure.
• A reservoir of predatory insects of plagues is achieved.
• Reduces the compaction of soil due to the passing of machinery.
• Controls the vine’s vigour.
And its disadvantages:
• Higher water consumption.
• Increase in the risk of spring frosts.
• Increase of weeds in spontaneous covers.
• Increase of plagues – reservoirs of plagues.
In short, the use of vegetation covers has multiple advantages in the vine’s productive process and in the obtainment of quality grapes. These advantages are realistic only in specific situations where the covers do not compete excessively with the vineyard. Vegetation covers are not positive as a general rule, the specific conditions of each vineyard have to be studied.
Can you imagine that it´s been a year now since we started to introduce you to the wine world through our Vinopedia videos?
This definitely calls for a celebration! Be prepared, for during the week of 13-17 of June we will put a set of questions on our Facebook Wall. Those of you who respond correctly to all these questions will enter drawing for a 12 bottle wine cooler, perfect to enjoy the wine in its best condition.
So this is your moment to show us what you know so, get ready to participate and, of course, spread the word. You will see that the questions will be very easy. Anyway, you can review our chapters to get yourself prepared for this fantastic opportunity.
Today we are going to show you a series of photographs courtesy of José Manuel Gómez, who is the person in charge of the vineyard in Castillo de Maetierra. By means of these images, you can more or less see how the vineyards are now, although they evolve so quickly that they are surely further developed by now. These past days are being rather hot and, as a result, the growth in this period is spectacular. The vine undergoes a radical change, such as Raúl explained in Chapter 3.
Also take a look at the soils in these estates; they are very interesting. In our next chapter, we are going to speak about the different ways of maintaining soils. Field work, non-field work… its advantages and disadvantages. We have gathered different opinions from people who defend field work in a really passionate way, and also others who prefer leaving the vineyards untouched. We will listen to their reasons and the advantages and disadvantages when following both options.
Meanwhile, here are some photos so you can enjoy the vineyard.
We promised, so here is the answer to the question that Ezequiel from Argentina made to us a few days ago. He asked us when was the best moment to plant a vine and how to do it. José Manuel Gómez, the person responsible for Castillo de Maetierra’s vineyard, gave us some indications. He says the best moment to plant a vine is when winter ends or the spring begins. This reduces the risks arising from freeze and, it will allow us to take advantage of the water accumulated during the winter and the spring showers. We will also take advantage of the spring temperatures, which helps them root and favours the vegetative development of the small vines.
However, there are many factors involved that we should take into consideration in order to plant a vine correctly.
1. Firstly, we have to consider the wine-growing and/or oenological objective pursued. Depending on this, we must choose a variety or varieties that we can plant, which at the same time will depend on the land’s wine-growing abilities, its location, arrangement, orientation, height and edaphoclimatic conditions, amongst others.
2. Another important decision is the rootstock, which shall depend on the type of soil comprising our plot, as well as its characteristics, for which a representative sample shall be essential. A main point to consider would be when choosing a rootstock, which shall be compatible with the variety chosen. We have to avoid incompatibilities with the variety.
3. An important factor would be to define the plantation pattern and its density, that is, the distance between plants in a same row and between different rows. This depends on the wine-growing objective, plot, inclination, shape, conduction system, type of pruning and available machinery, amongst others.
4. Deciding on the correct orientation of the rows is very important, which is usually a North-South orientation and slightly to the East at about 30º, in order to take advantage of the maximum solar radiation, although to a great extent this depends on the orientation, geometry and the slope of our plot.
5. We should also decide on the conduction system (trellis, gobelet, …) and the type of pruning (cordón royat, guyot, …), which will depend on the wine-growing objective, availability of labour, available machinery, etc.
6. Before planting, we have to prepare the land: subsoiling or ripping, levelling, drainage, soil liming, basal dressing, and the supplementary tasks carried out to help plant the vines.
7. Finally, planting is carried out, which can be performed in several ways. The most common are manually with a quoit – marking should have been carried out previously, mechanically with semi-automatic machines equipped with laser technology, and semi-automatic machines equipped with a GPS – which are the most precise.
Few days ago members of the Rioja Regulatory Council visited Bodega Classica, a winery situated in D.O.Ca Rioja. We were there to see how they collected the samples for analysis. These samples are to prove that the wines from Bodega Classica can be included under this D.O. This is an essential step so that the wines can be released on the market under D.O., in this case, D.O. Rioja.
Octavio, the oenologist from Bodega Classica explains the whole process in the video we made during this visit.
Some days ago, Vintae published a post in which they explained how this process is being undergone and how it is controlled that the quantity of wine that has been produced coincides with the quantity of grapes that were used in the winery during the harvest. This part, as we could see, is also supervised by a member of the Rioja Regulating Council, who was present when the grapes were introduced to the winery.
Few days ago Pedro, from Argentina, asked us a question about how to make a white wine with using additional yeasts. The question was as follows:
Hello friends from vinopedia, I am from Entre Rios, Argentina. I am a wine enthusiast and I would like to make a white wine in a very small scale for my own consumption. My intention is to perform the fermentation with the wineskins, but without adding yeasts. I would like to ask you if I have to monitor or be careful with anything else apart from the temperature and density. In which type of container should this fermentation be carried out? I would also appreciate any advice that comes to mind. Thank you very much in advance and congratulations for your Webpage, it’s excellent. Pedro
José Manuel Gómez, responsible for the vineyards in Castillo de Maetierra answers:
Hi Pedro, as you suggest, pre-fermentation maceration in cold temperatures with the aim of maximizing the variety’s aromatic potential is very advisable when making white wines. However, separating the wineskins and pips before starting fermentation is recommended. If we start the alcoholic fermentation with wineskins and pips, we run the risk of extracting excessive tannins from the pips, which will provide the wine with aggressive tannins, thus obtaining an excessively structured, astringent and bitter wine.
Once maceration is completed and the wineskins separated, performing a good clearing, with the aim of eliminating the deposits from the must, and obtaining a clean must before fermentation is important. This will result in a clean wine devoid of any unpleasant aromas.
As you state, you can make a wine without using yeasts; but, if you follow this option, you have to be very careful and consider some issues. Depending on where it is made, if it is being made in a bodega where it has been previously made, fermentation will start spontaneously with the yeasts present in the bodega itself and/or those present in the grape. However, if it is a new bodega, where wine has never been made before, if we do not culture yeasts, the fermentation will depend on the yeasts present in the grape itself, which are those present on its skins.
If choosing spontaneous fermentation, knowing the local yeasts is very important in order to avoid any risks, such as yeasts that will provide undesirable organoleptic characteristics dominating during fermentation, or yeasts that will not be capable of completing the fermentation to the desired point, although this depends on the type of wine we want to make (dry, sweet, semi-sweet, etc.).
Another issue to consider is the level of nutrients present in the grape, which is fundamental for the yeasts to complete their vital cycle. Its evaluation and contribution to the must is interesting if necessary. The lack of nutrients during alcoholic fermentation increases the risk of organoleptic issues appearing in the wine.
The best material to make white wines is stainless-steel, due to its harmlessness, easy cleaning and simplicity monitoring the temperature, either with a cooling jacket if we have cooling equipment, or by means of water showers. Another material used when making white wines is oak; however, monitoring the temperature and cleanliness is complicated when using these types of containers.
We hope we’ve solve your question. Thank you for following us!
You will be able to see our chapter number twelve very soon. There we will explain you what is malolactic fermentation and its effects on wine. In advance, we would like to explain how we monitor this process, which is triggered spontaneously as a result of the lactic bacteria naturally present in the wine.
You already know that after devatting, that is, after separating the wine from the grape skins, we leave the free-run wine in the deposits while waiting for the malolactic fermentation to start. As we do in all the stages of winemaking, we monitor everything that happens in our deposits, and in this case, we use a paper chromatography test.
What we do is we make a solution of butanol and acetic acid with a bromophenol blue indicator, and get a piece of cellulose paper. Once this solution has been prepared, we wet the paper with a drop of wine and introduce it into the previously mentioned solution (the yellow liquid you can see in the photo). The liquid will ascend the piece of paper, draw the wine’s acids and tint them so we can see them. The further it ascends, the more soluble is the wine’s acid in the liquid. Lactic acid is the most soluble, followed by malic acid and then tartaric acid. Thus, the highest stain on the paper corresponds to lactic acid, the one in the middle is malic acid, and the lowest is tartaric acid.
Here you can see how the liquid ascends as the malolactic fermentation is developed
Malolactic fermentation is the transformation of malic acid into lactic acid, which, on the other hand, is more pleasant on the palate. So, if after performing a chromatography test we see that the stain appears in a very low position, it is because malolactic fermentation has not triggered yet; what we have is tartaric acid. In the measure that we see the stain ascending, it means that malolactic fermentation is progressing, as lactic acid is slowly appearing.
When malolactic fermentation has ended, we will have a more pleasant wine on the palate and a more stable wine from a microbiological point of view.
From here on, we will let you know how we progress in the process of making the red wines. So, stay tuned!