Root Diseases

Numerous alfalfa root diseases have been documented in alfalfa fields. The severity of any one disease may vary from year to year and/or location. Various conditions may influence disease severity such as: Environmental Conditions, Rainfall, Soil Type, Irrigation, Elevation, Cutting Schedules, Nematodes, Cultural Practices, Soil Fertility, and Varietal Resistance to name a few.

How do I know if my alfalfa roots are healthy?
Check Roots For Damage

diseased crown

• Girdled or severed taproots.
• Brown or Discolored tap and lateral roots.
• New regrowth from severed tap roots.

Check For Internal Root Discoloration

diseased root vs. healthy root

• Healthy roots are white inside.

• Diseased roots will have Brown to Reddish Streaks inside the crown, taproot, and/or lateral roots.

• Extent of discoloration increases with severity of disease and/or age of plant.

What can I do If My Alfalfa Roots are Diseased?

• Existing disease problems are very difficult if not impossible to control. Disease severity increases over time.
• Depending on the root pathogen, some cultural and management practices may reduce the spread and/or severity of the disease (see individual disease). However these practices are generally not highly effective in preventing yield losses.

Will chemical applications control the root disease problem?
No. Chemical applications are generally considered ineffective or too costly.

How do I prevent Future yield losses from root disease?
Resistant Varieties are the only effective control.

How do I know what root disease is damaging my plants?
Dig up several plants and send them to your local extension agent, seed dealer, and/or University, for positive identification.