“Recent research has shown that red nets are more effective than black or white nets in preventing onion thrip damage to crops, reducing the reliance on harmful chemical pesticides by up to 50%. This approach supports sustainable farming by minimizing environmental impact.”
From this post: https://scitechdaily.com/the-science-behind-red-nets-a-new-dawn-in-eco-friendly-farming/
this is a complicated balance between plastic in the environment and pesticides in the environment !
A very good point! It’s too bad they are not made out of natural fibre twine that has been dyed or something