Weeds are far more difficult to remove from the lawn than grass weeds. Here is an overview:
Millet
Often occurs when there is a maize field or vineyard nearby. Broad leaf structure, likes to grow directly on the ground. Heavily covered with seeds, which should not fall off during control.
Annual bluegrass / Poa annua
Easily recognizable by its white flowers; one of the least popular annual grasses on golf courses;
Attention: purple flowers mean that it is Poa pratensis, which is desirable in the lawn.
(Common) couch grass / Elymus repens
Long creeping brown or white roots. The almost indestructible leaves are stiff. Not very dense.
Common panicle / Poa trivialis
Recognizable by the broader grasses. Common panicle emerges in spring. Light green leaf color. A reddish coloration can be seen on the stem.
White ostrich grass / Agrostis stolonifera
Very fluffy, very tread-resistant and low shear strength. Appears as patches on the lawn.
Bermudagrass
Bermudagrass is a so-called warm season grass and feels particularly at home in areas such as the south of the USA. Here in Europe, the grass goes into a kind of dormant state in winter, which is called dormancy. During this time, this grass does not look good, it turns almost completely brown and growth largely stops.