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Starthistle Biocontrol Weevil Video                                  

Art Talsma notes that it looks like this seed head has already been affected by the seed head weevil. If you look inside you can see little dark spots that are either the eggs they have laid or the beginnings of the larvae that feed on the seed head. Art finds a larvae of the beetle Eustenopis and the video shows close up views. Art notes that "this seed head has only three seeds in it and the larvae is healthy as can be. Look at how big he is."

Art points to a seed head and notes that the seed looks like a little miniature parachute. They will go back and analyze to see how many of these seeds are viable within a seed head. Lynn Danley, with the Bureau of Land Management has found that a good healthy Yellow Starthistle plant might have 60 to 100 seed heads and out of those 90 % were affected. And then in turn when she analyzed the seed heads themselves, even the seeds that were left were 90% not viable.

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