Disease Look-alikes and Normal Development of Alfalfa
It is important to be able to determine the appearance of a healthy alfalfa plant as it develops. This knowledge can help you figure out when a plant is unhealthy due to disease, insect pests, nutrient imbalance, environmental disorder, or other issue. Familiarity with alfalfa at various growth stages and stand ages, as well as cultivar differences, can help with problem identification. Genetic variation can cause an alfalfa plant to appear different from others, even within the same cultivar. Examples of variation include flower, root, and seed color and leaf spotting.
Alfalfa flowers can vary in color.
Iowa State University Integrated Pest Management Program
Illustrations of alfalfa plants at different growth stages.
Iowa State University Integrated Pest Management Program
Diseases can appear similar to alfalfa genetic variation, but there are ways to help tell them apart. Disease can spread from one plant to another over time, and disease severity or incidence may increase on a single plant. Genetic variation will not spread among plants or on a single plant.
Management of disease look-alikes is not needed.
Prepared by the Alfalfa Pest Management Working Group.
Alfalfa flowers can vary in color. Iowa State University Integrated Pest Management Program.
Illustrations of alfalfa at various growth stages. Iowa State University Integrated Pest Management Program.
Gallery images courtesy Iowa State University Integrated Pest Management Program.
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