Alfalfa can be grown on a various field from sandyto clay. Different soil structure may require specific management practices. Sandy soils may have excessive drainage requiring different irrigation strategies (sprinklers, rain irrigation & Center Pivot). Light soils also more frequently lack certain nutrients. Clay soils on the other hand maybe poorly drained requiring specialized drainage and production affect badly during Monsoon. Most fields that are flood irrigated need at a minimum a “touch up” on the slope to be sure there are no high or low spots for standing water. Standing water in Alfalfa field can cause severe lose in plant persistence and yield and if land is not reasonable leveled, sprinklers may be the only suitable irrigation method. Alfalfa requires well drain drained weeds free soil for optimum growth and production.Alfalfa fodder is known as Queen of fodder, belongs to leguminous family. Seeds are small with kidney shape. Due to its small size, the seed contains little energy to support seedling emergence from deep plantings, pushing thorough hard crusts, or to compete with weeds.Temperature and day length have plays significance influences on alfalfa seedling growth. Optimum temperature for germination and root growth are 18-25 0C while shoot growth optimums are 20-30 0C. When temperature is lower than 50C, there is essentially no growth. Daylength influences how seedlings use their energy to grow.When days are short (less than 12 hours), more energy goes to root development than to the foliage. Just the opposite is true when day length is longer than 12 hours. Unlike annual crops, alfalfa seedlings go through a process of development that includes a transition from a weak annual plant to a strong perennial with a well-developed crown and deep root. During this transition period, which typically lasts several months, the seedling is susceptible to diseases and in particular to weed competition.Land SelectionAlfalfa can be grown on a various field from sandyto clay. Different soil structure may require specific management practices. Sandy soils may have excessive drainage requiring different irrigation strategies (sprinklers, rain irrigation & Center Pivot). Light soils also more frequently lack certain nutrients.Clay soils on the other hand may be poorly drained requiring specialized drainage and production affect badly during Monsoon. Most fields that are flood irrigated need at a minimum a“touch up” on the slope to be sure there are no high or low spots for standing water. Standing water in Alfalfa field can cause severe lose in plantpersistence and yield and if land is not reasonableleveled, sprinklers may be the only suitable irrigation method. Alfalfa requires well drain drained weeds free soil for optimum growth and production.Phosphorous and potassium are the nutrients most often needed for alfalfa production, but in production belts of Rice, Maize & Sugarcane sulfur, boron, zinc or molybdenum may be required. The limitations of a field must be understood, and these limitations will guide practices such as deep tillage, design and installation of a proper irrigation systems (flood, sprinkler, Central Pivot), and development of a soil improvement program including integrated nutrients management.Tillage, Land Leveling and Soil PreparationDeep tillage is often recommended for alfalfa to improve rooting depth and water infiltration. Perennial crop require better tillage and leveling practices for good results. More stand establishment failures probably occur from too loose a seedbed and the alfalfa seed ending up toodeep.Seed Selection & TreatmentLot of verities has been developed in the world of alfalfa with great yield potential, better disease resistance and improved forage quality. The main factors leading to profitability are:1. Yield potential2. Persistence3. Winter hardness4. Disease resistance5. Forage qualityAlfalfa can produce nitrogen to fulfill own requirement by N- fixation through nodules whichare located in root system. To speed up this process of fixation a certain numbers of appropriate Rhizobia bacteria should be present in the soil So for good plant vigor and N-fixing capability, inoculation of alfalfa seed with the appropriate rhizobia bacteria before planting is essential.Even with a field that had alfalfa recently, treat commercial Rhizobia to seed are a way to assure that the bacteria is present in the field during establishment. Crop specific inoculants are easily available in Ayyub Agriculture Research Institute, Faisalabad or NARC, Islamabad.But Imported Seed from USA & Australia often come pre-inoculated. Seed and seedling disease of alfalfa can be significant problem which can cause of low germination, stand establishment and at the end low yield in poor drain soil. Seed treatment with Fungicide can reduce many alfalfa diseases.Sowing TimeOne of the most important techniques for successful stand establishment is to plant at the right time. Mid-October to end of November is the best time for alfalfa sowing. The optimum temperatures for rapid germination and growth occur in fall and late winter.During fall, when day length is short, root growth is favored over shoot growth but in the spring, shoot growth is favored by longer days. With fall planting, not only do short days promote root growth over foliage but it also provides more time for plant development prior to harvest compared to spring planting.Germination & EmergenceSeedlings emerge quickly (3-5 days) in the fall, compared to 10-15 days until emergence in end Nov/Dec. Optimum germination temperature is 18-25 0C. As soils warm, the rate of germination increase because of increased water movement in seeds and increases in metabolic activities of germination. Additionally, early-planted alfalfa produces a vigorous root system and crown formation is able to withstand the cold conditions and weed competition that comes in November-January.Seeding depth & RateAlfalfa is usually seeded with drills or by broadcast but the critical factors are accurate depth control and good seed-to-soil contact (achieved by using press wheels or rollers). Alfalfadoes not emerge if planted too deep. Poor seed placement (depth) is a very common cause of stand failures. Drill sowing with press roller is considered a reliable method for proper seeding depth, soil coverage, and firm soil‐seed contact is achieved.Seeding depth has a large effect on emergence. Seeding alfalfa at the depths greater than ½ inch makes difficulty for plant to pull leaves above ground, especially in heavy texture soils and plants are weaker most of energy utilize during emergence. Slightly lower seeding rates are recommended for drilled compared to broadcast seeding. Broadcast sometimes provides slightly higher yields the first harvest, but differences generally disappear after that.Bedded Alfalfa for Heavy Soils: Alfalfa is usually planted on flat, leveled soils but planting on beds has proved to be a highly effective technique for heavy, poorly drained soils. Beds allow water to drain off the field avoiding saturated soil conditions favorable for some diseases. Keep in mind; Beds are not as effective on sandy soils withrapid drainage.Plant PopulationGoal is to achieve 45-50 plants per square foot after emergence. Density will rapidly decline over the first year due to many factors like competition, weeds, climate and poor management practices. Thus even high seeding rates do not result in higher yields compared with recommended seeding rate. Paying more attention to seedbed preparation and to seeding depth is more important than increasing seeding rates. Reduction in seeding rates is an important cost-savings strategy, especially as the price of improved genetics increases the cost of seed.Minimum stand density required to maintain optimal alfalfa yields.Production YearStand density (plants/ft2)CommentsNew seedling stand>25 (range 25-80)Dense initial populationEnd of year 115-25Stand produces wellEnd of year 210-15Stand thinning but still viableEnd of year 3 & 46-10Consider over seedingFollowing Year< 3-5Replace standProviding Appropriate MoisturePre-irrigation has several advantag
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