What weed has thin orange roots?

The weed you are referring to may be "bindweed" (Convolvulus arvensis), which is known for its thin, orange-tinted roots. This perennial plant is notorious for its ability to spread rapidly and can be difficult to control. Another possibility is "yellow nutgrass" (Cyperus esculentus), which also features thin, fibrous roots that can appear orange. Both weeds can pose challenges in gardens and agricultural settings.