Some 20 years ago I had the opportunity (created by some innocent trespassing) to walk the pattern houses at the abandoned Ross-Meehan (ie, Meehanite) foundary in Chattanooga TN. The overwhelming majority of the large patterns were some species of pine and the small patterns, those needing to be attached to matchplates, were in mahogany.
Most of the patterns I have made have been in musical instrument grade hard maple or mahogany, because I had a source of scraps. The maple works beautifully as it can almost be machined like metal, but if the pattern is too large and made of a single piece of wood (instead of built -up in sections or laminations) there is the tendency for a turned pattern (ie wheel, flywheel) to warp across the diameter.
I recently considered making a pattern for a cast smokebox front for a locomotive and was in a Home Depot where I found their product called hobby "whitewood." Some of this was obviously soft, but some of it looked and felt like a good dense maple and would have made good patterns. I ended up not making the pattern as at the last minute I discovered I could buy a slice of the right-sized cast iron bar for a fraction of what the pattern-making and casting exericize would have cost. The other problem is foundaries . . . they're drying up one by one.