Two men who’ve known each other since sixth grade in Atlantic, Iowa, are making forty million dollars a year with a colorful idea. Roger Underwood says the agricultural colorant part of their international business began with a request.They were asked to add some coloring to Roundup herbicide so farmers would know where it had been sprayed and be able to keep it off the workers. Becker Underwood made a green spray that was used to touch up an entire cornfield for the movie “Field of Dreams,” and other colors followed, like a blue you may have seen at the U-S open last week in Oklahoma used to make waterways look nice. Underwood says not all the products of Becker Underwood are made to color things. He says bio-pesticide and bio-fertilizers are the other line, like an inoculant that helps roots use nitrogen better and plants need less fertilizer. And Underwood says a microscopic worm called a nematode is another natural product they sell, sprayed on crops to fight unwanted insects. The firm has labs in England and Canada, and sells more than 100 products all over the world. Becker Underwood’s annual 40-million-dollar revenue is expected to double within five years.