From the Small and Organic Farm Advisor Blog
Johnsongrass in organics: Mow it?
Yes, mow it! Mowing works to at least prevent seed spread and regular mowing will weaken rhizomes.
Seed establishment has the greatest potential for the establishment and spread of johnsongrass and must be prevented. Therefore, mowing works to at least prevent seed spread. An individual plant can produce 28,000-30,000 seeds and a single inflorescence can measure 1,240 seeds...
Johnsongrass? There's an app for that!
JohnsonGrass-JG (Android) and JG-JohnsoGrass (Apple) are apps for your tablet or smartphone that provided useful information about the biology, identification and management of Johnsongrass [Sorghum halepense]. It also contains a “Record” feature that allows the user to help map the distribution of the weed and its spread over time and space.
An important, noxious weed
Johnsongrass is considered a top 10.../h3>/h3>