Yes, tumbleweeds is a Scrabble word!

Noun

1. Any plant that breaks away from its roots in autumn and is driven by the wind as a light rolling mass

2. Prickly bushy Eurasian plant; a troublesome weed in central and western United States

3. Bushy annual weed of central North America having greenish flowers and winged seeds

4. Bushy plant of western United States