Future dandelions.

The future looks bright for next years dandelions. That's not a good thing. Many alfalfa fields are full of dandelions. As explainded to me, when the fields are irrigated the seeds tend to float. The excess irrigation water flows into a ditch where upon that water is them transfered into another field. Thus, the seeds are spread. You can't use an herbicide because the chemicals that kill the leafy dandelion also kill the leafy alfalfa. You have to spray the entire field and start all over again with a new seeding. But, 10 years later, you have the same problem.