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Eight factors that can determine alfalfa success

Jeremy Hayward Published on 31 January 2015

There are a number of factors to consider when choosing alfalfa seed and fashioning your overall forage management plan, including yield potential, stand persistence and winter hardiness, disease resistance and forage quality.

Following are tips for making sure you’re selecting the best seed for your specific fields and covering what is necessary from a systems management perspective to help maximize yield potential.

1. Fall dormancy. Unlike selecting corn hybrids or soybean varieties, alfalfa is less geographically impacted, which is why fall dormancy is so important. Fall dormancy choice is a good indicator of what the grower’s goals are and how a variety will perform during the growing season.

Of course, these goals depend on things such as management style, cutting frequency and quality objectives.

2. Soil fertility. Alfalfa is a foundation crop. Consequently, prior to planting it is important that baseline fertility is achieved. Alfalfa is not a crop you can plant, then catch up on pH, potassium and phosphorous.

Working with an agronomist who understands overall alfalfa management is crucial – not only for seed selection but from an overall systems perspective on soil fertility and how alfalfa fits into your cropping system.

Remember, when fertilizing for alfalfa, it’s important to satisfy not only base fertility levels but to fertilize according to nutrient removal based on yield goals.

3. Seed treatment package. Most seed treatments contain an inoculant with a high rhizobia count. But there are other components that are also important. Some seed treatments include a growth promoter, which initiates early nodulation and greater seedling vigor to give young alfalfa seedlings a boost.

Some seed treatments include a base fungicide to stave off seedling diseases and a second fungicide for additional phytophthora and aphanomyces root rot resistance.

This gives growers additional resistance to aphanomyces and other seedling diseases that are prevalent (in addition to the resistance built into the variety), extending resistance to these types of diseases for as long as 45 to 60 days.

With the advent of many new seed treatments in corn and soybeans, similar technologies are perhaps even more important when utilized on alfalfa, which traditionally has a relatively high mortality rate. Therefore, it’s important to keep as many of these seedlings alive and thriving as possible.

4. Data. Reliable data can aid in comparing alfalfa varieties and in making decisions about which varieties to plant. It’s important to view data in terms of trends against competitive checks, how your alfalfa varieties compare in geographies similar to your own and how they perform over a number of years.

5. Glyphosate resistance. If you have broad-spectrum weed pressure and a long growing season, planting glyphosate-resistant alfalfa varieties makes a lot of sense – both as an establishment tool for thicker, cleaner stands and for the likelihood of higher populations, improved yield potential and greater persistence.

If you are going to plant alfalfa with grass, glyphosate-resistant varieties may not be a necessity, although they can still be an option by utilizing glyphosate to get the stand started, then establishing grass at a later time.

6. Potato leafhopper resistance. Especially in the Upper Midwest and northeastern U.S., purchasing alfalfa varieties with high leafhopper resistance could be key, particularly if you are not aggressively monitoring for leafhopper presence.

Even moderate levels of potato leafhopper can have a negative impact on yield potential. So if you’re not actively scouting for and controlling potato leafhopper, it’s wise to plant alfalfa varieties with high leafhopper resistance. Leafhopper damage can typically be misdiagnosed as dry weather taking a toll on the plant, or as a nutrient deficiency.

But if you scout, you may find leafhopper presence that warrants spraying. With the price of alfalfa hay today, we’re at an economic threshold that’s lower than it used to be when hay was cheaper. So it makes sense to scout and spray a little earlier than you might normally.

If you have alfalfa stands that contain grass, leafhopper damage again may be masked or blamed on sulfur deficiency or drought. In these instances, it can be very beneficial to plant varieties with good leafhopper resistance. Bottom line: Stay on top of potato leafhoppers, and if you don’t, plant a variety with top-tier resistance.

7. Forage quality. Don’t ignore forage quality data, though it may be challenging to access. Compare varieties to gauge relative forage quality (RFQ), fiber digestibility (NDFd), crude protein levels, milk per ton and other measurements against comparable products.

8. Quality seed. With overall production costs climbing every year, it may be tempting to look for ways to cut expenses. Purchasing an older-generation, less-expensive seed is one alternative, but those short-term input savings may come at the cost of long-term profitability.

You will have to live with your alfalfa stands for a number of years and through multiple cuttings. Seed cost is something some growers weigh with many crops, but with alfalfa, considering the price of cash hay, purchasing the higher-quality seed is no contest.

Working with an agronomist who understands overall alfalfa management – including fertility, weed management, insect control and cutting management – is extremely important.

Your agronomist needs to have a keen understanding of your forage goals and what it takes to achieve them. It’s also critical for both you and your agronomist to seek out credible research that helps you select the best alfalfa seed for your fields.

Talk with your agronomist about consulting with a forage nutritionist to ensure your alfalfa has consistent quality that will be beneficial for your operation or for dairy and beef producers to purchase.

Bringing all of these factors into play will go a long way toward helping you realize optimal yield potential and a successful alfalfa harvest in 2015 and beyond.  FG

Jeremy Hayward
  • Jeremy Hayward
  • Brand Manager
  • W-L Research