Flowers Look Like Cotton Buds

A quick glance made me think that these flowers are cotton buds. My sister pick a few bunch and put them on this vase. I thought she was just being creative to use some cotton buds to create this arrangement but I was wrong. These are real flowers that she saw growing by the roadside that do not need care. Could they be a type of wild grass?
This is how they look like when the buds open. Not bad but the unopened buds look more intriguing for me that is why they got me snapping a few photos just like these on my post today. I will observe if they would last for a few days because I will continue gathering them when I can and decorate our living room even if they do not have any scent.

Have a blessed day