There are many agricultural discussion groups on the internet covering a wide range of topics.
Discussion groups operate via e-mail.
Servers called Listserv's receive and distribute postings. When you subscribe your name gets added to the mailing list. If you wish to post to the discussion group you only need send one e-mail and the listserv will send it out to all the members. Remember someone else is paying for all those e-mails so try and respect that. Most groups have help files which shouold be read before posting for the first time.