Alfalfa

Alfalfa (Medicago sativa L.) is a leguminous plant that can be cropped several times per year. It plays an important role in providing vegetable protein that can be used in animal feed.

In addition, being leguminous, alfalfa helps fix atmospheric nitrogen as a result of the symbiosis between its root system and ehizobium meliloti bacteria. Hence, the plant provides a raft of agronomic advantages, given it is a crop that improves the soil both through its nitrogen fixing and its contribution to improving soil structure. Thus, alfalfa cultivation is a key member of the leafy crops used in each rotation.

Compared to alfalfa on the plant, dehydrated alfalfa includes the advantage of a homogenous quality throughout the year. FORSA sells the end product in the form of bales.

Control and monitoring

Alfalfa needs to be monitored from the field all the way to the factory to ensure only the finest quality. This requires specialised operators exercising control and monitoring of the crop to establish the best moment for reaping and harvesting, in addition to checking for possible pests that may appear on the land.

The work begins with identifying the land to contract, followed by production of the cutter Wheel. Thus, the order for cutting is determined for the plots, along with the planning for the fieldwork required and the reception of the chopped alfalfa in the factory. This enables it to be processed daily with a quality product obtained at the end of the process.

Sowing

The most typical work done prior to sowing alfalfa tend to be vertical tasks, such as subsoil and chisel work. However, with plots predominantly used for crops such as corn, harrow, ploughs and milling machines are often employed to dig in the plant layer. It is important to highlight that the seedling bed must be prepared as well as possible. Aside from assisting seed growth, this practice will also make later reaping and harvesting labours easier, hence rolling is an important activity to maintain here.

Sowing generally takes place in the spring and autumn, accompanied more and more by applications of herbicide to control weeds and, thus, ensure the quality of the alfalfa. Certified seeds should be used when sowing as they are free of cuscuta and other weeds. The most commonly used variety is the ‘Aragón’, which is used at about 35-40 Kg/Ha.

Reaping

Alfalfa reaping tends to start at the beginning of April, while the regularity with which it is cut down depends on the plant’s flowering pattern. The crop tends to be cut somewhere between every 26 and 32 days towards the beginning and end of harvesting, with 28-30 days the typical during the hottest part of the year. This means that there are 5-6 cutting sessions during the alfalfa campaign on irrigated land.

The height of the cut is normally about 4 cm, though this does depend on the machine used. Disc-based harvesters usually leave less stubble than the serrated version. Large plots that are spray irrigated are often harvested using self-propelled serrated harvesters, which helps speed up the drying process.

Raking

Raking is done to reduce the drying period of the alfalfa in the fields and ready the final cords being used to bale the alfalfa that will be collected by the harvester.

Raking does not happen at any fixed time or on any particular day. It needs to be done with enough moisture in the plant, so the alfalfa does not lose its leaves, though sufficiently little moisture to ensure the drying process.

The machines used for this work should be regulated to ensure the tines do not drag stones along as the reduction in the quality margin of the plant may cause significant damage to the harvester. The best work is achieved with “book”-type rakes (or those with rotors). Do not use a “sunflower” rake as this type tends to dredge up too many stones.

Harvesting

Alfalfa harvesting is a delicate matter throughout the cycle, given it is this that ensures a good end product. There must be good on-site monitoring prior to beginning the work to identify exactly when the alfalfa should be harvested.

Harvesting occurs at night during the summer, while in cooler months or when there is more dew at night, harvesting is often done last thing in the morning or during the afternoon. This necessitates operating with alfalfa in optimum conditions in terms of moisture, some 30-40%, though it will also depend on the type of machine being used.

The drying period in situ is about 3 days following reaping, though this is dependent on the weather, the harvesting system, raking, cutting equipment, and the number of days without irrigation prior to reaping.

Factory

The product is controlled upon reception at the factory, thus bringing to an end the cycle pre-established in the field. The periods of maximum production are thus regulated, preventing the arrival of more alfalfa than can be dealt with on a daily basis. This also ensures there is no fermentation occurring, something that would lower the quality of the end product.

The product is distributed in the reception area according to its moisture content and quality, ensuring processing is facilitated and the classification of the alfalfa into homogenous batches.

Market demand in recent years has seen alfalfa producers being more meticulous on this point, pursuing harvesting undertaken in teams and not by individuals.

Sampling & analysis

When the alfalfa arrives at the factory, the trailers are weighed. Once the alfalfa has been unloaded, various representative simples are taken for analysis purposes.

Controls start with a visual inspection, which determines the classification and distribution in the area of the dehydration plant. Then, in the factory laboratory, other features are analysed, based on the amount of moisture found in the alfalfa and measuring its protein.

Drying ovens and NIR Infrared meters are employed for this analytical process. Efficient quality control serves to classify the product prior to processing it, which facilitates organization of the batches of bales afterwards.

Packing & labelling

The alfalfa dehydration process culminates with the packing stage. However, a final control needs to occur prior to storage that comprises testing the moisture in the bale. If the result is acceptable, the bale is given a label identifying the producer of the bale (FORSA, in this case) is affixed to the bale.

The final stage concludes with the storage of the bales, classified by batches with similar characteristics, ready to be sold.

The end product, evidently, is a a bale of dehydrated alfalfa that weighs either 450 kg or 750 kg (measuring 110x110x85 cm or 220x110x85 cm, respectively) and is of the best quality to enable livestock to make the best use of the product per their needs.