In the midwest maybe other places as well if your seeing dangling flower heads. The damage is likely caused by the sunflower head-clipping weevil.
A well known pest of sunflowers has taken a liking to our coneflowers.
Then there are the mites and aster yellows. At this time the mites are known to only to cause flower damage. While aster yellows affects the plant and flower. Explained below if you wish to read on.
The eriophyid mite that is affecting the flowers of echinacea still has not been scientifically name and has no approved common name. The mite is being referred to as the coneflower rosette mite. Eriophyid mites are highly plant specific and these are not the same mite affecting our roses. The rose eriophyid mite is phyllocoptes fructiphilus Keiffer. The current name used for the coneflower mite 'rosette mite' refers to the damage done to the flower. At this time it appears the damage is limited to the flower only. The mite lives deep within the flower bud where it feeds and lays its eggs. Thus putting the mite out of the reach of miticides. Removing and destroying the flowers is considered the bast method of control. Eriophyid mites tend to exit their host during rain events. When they can easily be picked up in the wind and dropped on new plants. They are also suspected of hitching rides on insects and even clothing.
Aster yellows is a chronic, systemic plant disease caused by a bacterium-like organism called a phytoplasma. You will see plant damage as well as flower distortion. Know to be spread by aster leafhoppers who make their winter home in southern areas. Each spring they will migrate northward.
Any leafhopper feeding on an aster yellow infected plant carries the disease for the remainder of it's lifespan. It will then infect any plant on which it feeds. Aster Yellows can affect more than 300 plants in 48 families. This includes a wide variety of field crops, vegetables, ornamentals and weeds. Once again control with pesticides is not reccomended. Control with pesticides is spotty at best, and kills off natural predators. It is best to removed affected plants as soon as possible.
Here is a listed of plants affected which are likely to be in our gardens.
vegetables= anise, broccoli, cabbage, carrot, cauliflower, celery, chicory, dill, endive, white mustard, escarole, lettuce, onion, parsley, potato, pumpkin,
radish, shallot, spinach, squash and tomato.
ornamentals= aster, rudbeckia, helenium, heliopsis, canna, chrysanthemum, delphinium, flax, gladiolus, marigold, phlox, veronica and zinnia.
Quite certain I've missed a few. I'm guessing that the point here is if a plant doesn't appear healthy it is best removed so as not to spread a disease to the rest of your garden.
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