trichoderma

Hi, Does anyone use Mycorrhizae & then a few weeks later apply Trichoderma? Cheers.

Would capturing and using the green trichoderma found growing on onion roots from the supermarket be a free source of trichoderma? Take some and scrape it into a compost tea fror example. Or is this a horrible idea? Could it backfire and harm the plants? Like if its the wrong species of...