Tradator: only the calendar spreads (one month vs other month same commodity) are traded as a spread, but the CME recognizes many spreads, but they have to be legged. (not hard with any elec. order entry like X-trader). For a complete list of the spreads, I've attached a link to the CME page. Go to the CME ags, CME forestry, and the CBOT ags to get all of the info. http://www.cmegroup.com/CmeWeb/html.wrap/wrappedpages/clearing/pbrates/PBISHomePage.htm?h=2
Thanks a lot TraderTX, That was my point, there are no distinct order book for intercommodity spreads. It is harder to make a market when you have to leg in, although I understand it can be done with dedicated software.
Trade long term, with low to no leverage, following main trends. All commodities/foreign currencies are moving more and more in unison, and will continue to do so.