What limits are placed on weed seed content in seed lots?

In California Seed Law, there are strict regulations regarding the acceptable levels of weed seed content in seed lots to ensure agricultural integrity and prevent the spread of invasive species. The maximum percentage of weed seeds allowed in seed lots is established to maintain crop quality and protect the environment from potentially harmful species. The limit set at 1.5% reflects a balance between allowing a small degree of weed seed presence—since complete elimination can be unfeasible—while also imposing limits to prevent significant negative impacts on crops and natural ecosystems. Thus, the regulation is designed to aid farmers and land managers in maintaining productive and sustainable farming practices by keeping invasive weed species in check.