(August 2008) Alfalfa producers can evaluate their stems to predict current yield, but the roots are used for predicting a stand's future yield potential.

"It's easy to be fooled that a stand is healthy when a grower simply walks around and looks at their crop," says CROPLAN GENETICS® brand forage product manager Dennis Gehler. "A plant can be nice and green on top, but it can also have lots of decay or disease stress in the root. That's something a grower won't know unless they start digging the plants."

Reading the stand consists of randomly digging several plants from 10 separate locations throughout the field, splitting the crowns and looking for any noticeable discoloration in the roots. Then the plants are scored under the following scale:

• Healthy plant: 0 points
• Some discoloration: 1 point
• Moderate discoloration and rot: 2 points
• Significant discoloration and rot: 3 points
• Discoloration greater than 50 percent: 4 points
• Dead plant: 5 points

Stands with an average root score between 0 and 2 points are thriving and should be kept in production. Stands with average scores between 2 and 3 points should be considered for rotation and those averaging between 3 and 5 points should be rotated out of production.

"Growers tend to be reactionary in terms of rotational decisions," Gehler explains. "When a grower waits for their alfalfa yield to decrease before rotating their crop, it means they're a year or two behind in rotating the stand. Reading the stand is about evaluating the health of the plant and predicting its productivity a year in advance so the grower can avoid the stand's least productive years."

Reading the stand is not difficult, nor is it a new concept. Farmers can do it themselves, but many ask their local agronomist to come out and perform the task so they can get additional recommendations that will ultimately lead to enhancing the stand's health.