The alfalfa (Medicago sativa L.) also called Spain grass, or alfalfa (from the Arabic al-fáṣfaṣa "forage") is a herbaceous plant belonging to the Fabaceae (or Leguminosae) family.
Origin and diffusion
Alfalfa has been called the "queen of forage", a definition certainly deserved.
It is generally agreed that Southwest Asia is the most likely center of origin for alfalfa and its cultivation as a fodder plant can be traced back to over 2000 years ago. It was in fact known by the Greeks and Romans.
The main center of diffusion of its most recent expansion would have been Spain, where it seems that it was re-established by the Arabs at the beginning of the eighth century.
It is estimated that the total area planted with alfalfa is approximately 15 million hectares.
In Italy it is grown in Emilia Romagna, (more than half of the total Italian surface), followed by Lombardy, Marche, Lazio, Umbria, Abruzzo, Tuscany, Veneto and Campania.

Botanical characters
The cultivated alfalfa belongs to the Medicago sativa and M. media species of the Trifolieae tribe. Medicago media, considered by some to be a form of M. sativa rather than a species in its own right, is derived from the spontaneous crossing of this with M. falcata.
Common alfalfa (Medicago sativa)
it is a species native to the Iranian highlands, that is, from the ancient Media; it is a lively herbaceous plant that could live up to 10-15 years in suitable environments, but which generally lives much less in cultivation (3-4 years) due to various adversities.
The seed is small (1000 seeds weigh about 2 g), kidney-shaped, greenish yellow in color; a certain percentage of seeds (8-10% and sometimes even more) are hard but must be considered as normally germinable. From the seed comes a taproot that penetrates quickly into the soil and usually reaches well over one meter.
The alfalfa plant consists of numerous erect stems 0.80-1 m high, which develop from the clump after the previous stems have been harvested. This rapid drop that regenerates the vegetation after each cut is one of the most important and appreciated characteristics of this forage.
The leaves are trifoliate; the leaflets are elongated and denticulated in the upper third of their margin; the leaflets make up about 45% of the weight of the whole plant and are the most nutritious parts.
The flowers of the common alfalfa are formed in number of 10-20 on small axillary racemes and are blue-purplish in color.
The fruit is a spiral legume, which usually contains 2 to 8 seeds.
Medicago sativo is a moderately cold-resistant plant, as it tends to continue to vegetate even during autumn, thus remaining exposed to the damage of subsequent low temperatures. On the other hand, it is very resistant to heat and dryness.
Variegated alfalfa (Medicago media or M. varia)
It is very similar to common alfalfa: it differs from it only in having undergone the spontaneous crossing with Medicago falcata. This is a wild alfalfa, native to western Siberia, widespread throughout Europe and Asia, characterized by bundled roots, narrow leaves, yellow flowers, sickle-shaped legumes.
It is a plant very resistant to cold as in autumn, under the action of short days, it stops all vegetative activity: it is this winter "lethargy" that gives the plants their resistance to cold. Furthermore, resistance to heat and dryness is limited.
Variegated alfalfa is so called because the genetic contribution of M. falcata produces greenish, bluish, yellowish or even brownish shades on the blue-violet background color of the flowers.

Environmental needs and cultivation technique
The dual geographic and genetic origin of the medica means that this plant is grown within a wide range of latitude.
In the hot and arid environments of the Mediterranean basin, the cultivated populations of alfalfa are referable to pure M. sativa; in areas of central-northern Italy and, above all, in central Europe, where resistance to cold is important for survival, the medical herbs grown are of the "variegated" type
Alfalfa is a strong consumer of water: it consumes 700-800 liters to form a kilogram of dry matter; despite this, it is the most resistant to drought forage thanks to its root system capable of going down to great depth, as long as there are no obstacles.
Alfalfa is very afraid of excess moisture in the soil, good hydraulic land arrangement is essential for the persistence of the alfalfa.
The most suitable soil for alfalfa is that of medium texture and that of clay with a good structure, deep, so as not to hinder the deepening of the roots.
With regard to the pH, alfalfa does not tolerate acidity.
Place in the rotation
In the past the doctor was kept for an unspecified number of years and kept out of rotation. Currently the standard is to use the lawn for 4-5 years, inserting it in rotation.
Alfalfa has always been considered a great improving crop that usually follows and precedes wheat, entering into rotations of different duration and type.
The only incompatibility of alfalfa in terms of crop succession is towards itself.

Soil preparation
In the case of piercing sowing, ie overseeding of alfalfa in wheat, no special preparatory work is required.
In the case of specialized sowing, a profound work, to be renewed, is very appropriate to favor radical deepening. This work must be done early in the summer, in order to have the time to achieve that state of perfect surface refinement that the smallness of the seed makes it essential for sowing to be successful.
In the case of the availability of a sprinkler irrigation system, a technique that gives good results is to sow the alfalfa in the summer on wheat stubble subjected only to "minimal processing", that is, to surface harrowing.

Fertilization
The basic fertilization for the medic is based on phosphorus, of which legumes are extremely demanding; nitrogen is not important given the nitrogen fixing; potassium is generally abundant in soils and regions where the medicament is widespread. It is advisable that the phosphoric fertilizer, and any potassium fertilizer, is given before sowing or, better still, before plowing. In order to enrich the deep layers in which the root system will operate with phosphorus.
Manure would be very useful to the doctor for improving the physical properties of the soil, to which the doctor is very sensitive.

Sowing
Alfalfa can be sown:
- 1 At the end of the winter from the moment the temperature reaches 5-6 ° C;
- 2 In late summer so that the seedlings can reach a good epigeal (4-5 leaves) and root development / at least 50 mm) when the cold arrives; in fact the alfalfa seedlings when they are very young cannot resist the cold.
Sowing at the end of winter (February-March) is the most practiced if there is no irrigation possibility; being able to do one or two auxiliary irrigations, to ensure the emergency, summer sowing is undoubtedly the most rational.
Sowing can be done in different ways:
- 1 In a hole in the middle of a cereal;
- 2 Sowing in purity on bare soil, mostly in spring;
- 3 Sowing in purity in summer after a cereal, with auxiliary irrigation.
Sowing can be done by broadcasting, burying the seed with a very light harrowing, or with the wheat seeder, in rows 0.14-0.16 m apart. it is of the utmost importance to ensure that the burying of the seeds is not excessive: 20-30 mm is the maximum depth at which the seeds can be laid in order for them to be able to grow.
Amount of seed
To have the 350-400 plants per square meter that is considered the best initial stand of a medic, it is to be assumed that by taking care of the perfection of the seedbed and sowing fully satisfactory results can be achieved with seed quantities not exceeding 15-20 Kg / ha.
In many cases, rolling can be useful in promoting births.

Cultural care
The phosphate and phospho-potassium fertilization in coverage of the medicio, even if it is a current practice, is not very rational given the low mobility of these elements, as it has been said P and K should all have been given before sowing.

Weed control
During the planting year, the most common infestations of alfalfa lawn are annual dicotyledons (Stellaria, Capsella, Sinapsi, chenopodium, Amaranthus etc.), or annual monocotyledons (Digitaria, Setaria, Echinochloa). Subsequently, polyennial dicotyledons such as Taraxacum, Rumex, Plantago, or monocotyledons such as Alopecurus, wild oats, ryegrass, Agropyron repens appear: even if not devoid of a certain forage value, they are however to be considered as weeds of the otherwise highly prized alfalfa. Dodder is also very fearsome and can cause extensive thinning like wildfire. Maintaining the purity of the alfalfa lawn guarantees both the longevity of the lawn and the quality of the forage, which is maximum only in the case of pure alfalfa.
Weeding alfalfa can be articulated as follows:
the possible interventions at the medical facility are:
- 1 Pre-sowing
- 2 Pre-emergency
- 3 Post-emergency
In the implanted medic
- 1 During the vegetative rest.
- 2 At the vegetative restart.
- 3 Control of dodder. This parasitic phanerogam causes severe thinning in patches on alfalfa from the first year. The specific fight is that based on Propizamide, to be done localized or across the board immediately after mowing.

Irrigation
Cases of irrigated alfalfa are limited, preferring to allocate the water to crops that are more reactive to this technical means, such as those for renewal, the hortens or, among the forage crops, spring-summer and summer weeds. Only in the extreme southern regions with an excessively dry and hot climate, irrigation is necessary and is an indispensable condition for obtaining constant and high production.

Variety and use
The centuries-old cultivation of alfalfa in environments variously characterized from a podological, climatic and phytosanitary point of view and the repeated use of the seed obtained on site had over time determined the formation of ecotypes, with highly appreciable characteristics of adaptation and productivity.
Recently, following different selection methods, improved varieties have been established, which have particular qualities of productivity, resistance to adversity, duration, speed of re-throwing after cuts.
Since 2000, the trade in alfalfa seeds has been limited to selected varieties, with the exception of ecotypes.
In the year of sowing, production is poor. Full productivity is reached in the year following sowing, and in the 3rd year the production begins to decline due to progressive thinning. When it drops below 100 plants per square meter, the medic must be broken because its yield is compromised.
During the year, the alfalfa supplies its product, grass, in several cuts: from a minimum of 2, in the case of arid climate and soil, to 4-5 in irrigated or very fresh conditions; extreme cases occur in the irrigated crops of subtropical areas (oasis of deserts) where the alfalfa, vegetating all year round, gives up to 10-12 cuts of very young grass.
The optimal vegetative stage for cutting is when flowering has begun a few days ago.
Alfalfa is used in green or hay foraging, ensiling is not very common.
Alfalfa grazing is to be done with caution because young grass can cause meteorism to ruminant animals, a pathological and even fatal syndrome that consists of the abnormal swelling of the rumen.
Haymaking is rather delicate, especially at the first cut where the grass is coarse due to the presence of weeds, and the season is not very favorable due to rainfall, air and soil humidity and low solar radiation.
The average annual yield of alfalfa meadow hay can reach up to 13 t / ha, in more normal conditions the yields are around 8-10 t / ha.
An excellent quality alfalfa hay has a raw protein content of 18-22% (on s.s.); the nutritional value is about 0.6 U.F. per Kg of s.s.
The hay harvest must be done with great care to avoid that by handling the forage that is too dry, the leaves, which are the most valuable part, are lost.

Seed production
Alfalfa seed is only exceptionally produced in specialized seed culture. As a rule, the seed is produced on forage crops as an ancillary production, generally the last year's medic is left to go to seed, after mowing the maggengo cut.
The ripening is rather gradual, so the harvest is accompanied by ripe legumes next to green parts that hinder the use of the combine harvester.
The yields of alfalfa seed on average are around 200-300 kg / ha. A rather serious adversity is the dipteran insect Contarinia medicaginis, or alfalfa caecidomy, which causes the abortion of numerous flowers.

Adversity and parasites
A formidable adversity is lodging, which is frequent especially in the vegetation of the first cycle, which usually mows in May.
Among the plant adversities we remember:
- 1 bacterial wilt (Corynebacterium insidiosum),
- 2 Leaf spot (Pseudopeziza medicaginis),
- 3 Anthracnose (Colletotrichum trifolii),
- 4 Mal vinato (Rhizoctonia violacea),
- 5 Root rot caused by Fusarium roseum, Verticillium alboatrum and other fungi.
The leaves are often rose from the Apion, from the weevil (Phytonomus punctatus); the sprouts can be attacked by the medical measure (Biston graecarius).
Alfalfa seed crops are often severely damaged by cecidomy (Contarinia medicaginis).
A serious adversity of alfalfa is dodder (Cuscuta spp.), A parasitic phanerogam plant, which wraps around the stems of alfalfa with its yellow filaments and causes thinning in a circular patch.

Collection
To be used as a fodder, alfalfa must be harvested from the field in the first days of flowering.
It is then, using increasingly advanced equipment, mowed and dried in the shortest possible time.
Drying takes place in the field, turning and preparing the plant, taking care not to lose the leaf until it is dry enough to be packed and stored.
Packaging takes place only when the plant does not exceed 15% humidity level to allow the maintenance of the physical and nutritional properties of the medic.

Products

From the annual production we obtain various qualities of alfalfa with different properties:
• 1st mowing, mainly composed of hay and a small percentage of alfalfa, perfect for all ruminants and equines.
• II ° Mowing, composed entirely of alfalfa with a protein intake from 13 to 15%.
• III ° Mowing, composed entirely of alfalfa with a protein intake from 15 to 16%.
• IVth Mowing, composed entirely of alfalfa with a protein intake from 16 to 18%.
• “Green” alfalfa collected in round bales before being dried, to be wrapped with nylon, produced exclusively on the customer's prior request.

For each variety there is a different price to be agreed with the customer.