Ironweed can be an aggressive weed in moist soils.

Containers almost inevitably have weed seeds in them, and invariably bittercress, an aggressive weed that I can manage without.

Damage to crops from weather extremes, aggressive weeds and voracious pests is a fact of the present.

It will form dense mats which can take over areas of lawn, and thus can be considered potentially invasive or aggressive weed.

Scientists describe it as a "poisonous, allergic and aggressive weed posing a serious threat to human beings and livestock."

Many exotics have also become aggressive weeds in the garden.

It sometimes becomes an aggressive weed.

Outside of its native range, this vine is often a very aggressive invasive weed.

Recent publications mention the species as an aggressive and invasive weed in the warmer parts of North America.

Even butter-and-eggs and the dandelion-like coltsfoot become aggressive weeds if not kept in their places.