Survey of Italian Ryegrass in Delaware and Maryland

Mark VanGessel, Extension Weed Specialist;, Kurt M. Vollmer, Extension Weed Management Specialist, University of Maryland; 

The number of questions about Italian ryegrass increase every year and it seems as if Italian ryegrass is in many more fields this year than in the past. Therefore, we are interested in investigating what is going on, by gathering seeds from as many fields as possible for some greenhouse testing to see if populations are responding differently to herbicides. We are looking for some help in collecting seeds.

Figure 1. Italian Ryegrass Seedhead

Figure 1. Italian Ryegrass Seedhead. If seedheads are smaller than shown-here, then increase the number collected.

How can you help?

  1. Collect 50 ryegrass seedheads from the field (only seedheads are needed).
  2. You do not need to wait for the seedheads to dry down.
  3. Put in paper bag or paper envelope (do not use plastic bags).
  4. Write the nearest crossroads on bag or envelope.
  5. Write the crop on the bag/envelope.
  6. Note if any of the following herbicides were sprayed since last fall:
  • glyphosate (Roundup)
  • Axial
  • PowerFlex
  • Osprey
  • Select
  • Assure II
  1. Store in dry area.
  2. Deliver to nearest county extension office


Contact Mark VanGessel or Kurt Vollmer for collection or pickup.

Mark VanGessel        302-542-8160

Kurt Vollmer              443-446-4260

Specific farms or individuals will not be identified in any reports or summary.