I'm planning the exact same project for my house. 60ft long wall, 7-9ft high (depending on what the building department will allow) made of straw bales. Get yourself a good book - libraries rock! I've researched this and you want to have a concrete reinforced foundation for the wall. Have rebar sticking up out of it every 2ft or so inbeded in the concrete. The rebar can be anywhere from 18" - 3ft... it's kind of preference. Have bolts imbeded in concrete near the edge of foundation every 3ft or so (think like in line with railroad tracks) The foundation MUST be 6-8" above soil so moisture doesn't wick into bales. Attach Trex or presure streated 2x4s to bolts as a kind of mudsill - now it should look like a rail road track wall. Fill gap inside with gravel for drainage incase any moisure gets into wall it can drain out bottom. Buy high compressed rice bales - rice material has higher mold resistance. Now get some buddies that owe you and have a straw bale implalement party! Basically implale the first row of bales on the rebar sticking up. Now stack the second layer, staggering the bales like bricks on a wall. Now drive in more rebar (3-4ft long) between the 2 layers so some is sticking up for the third layer (this can also be done with sharpened wooden sticks). Now do the next layer, staggered, and drive some more stakes through. Continue until wall is desired height. Now get a whole bunch of lath like boards, as tall as your wall, and lean them against the wall every 2 ft or so on both sides of wall (each board/stick should have a buddy in the same location on the other side of the wall). Now you need a whole lot of ridged wire to thread through the bales, wrap around the opposide stick, and return to the stick on the other side, tie together tight and move 8" up and do it again and again. This wood is what you will staple the stucco wire to and it cinches the bales tight and adds extra support. Staple tar paper over sticks or it will crack the stucco. Staple 2x2 wire first, then 1.75 - 3.5 awg wire (1.75 is thin and easy to mold around corners, 3.5 is stiffer if you want even more support). Now comes the stucco. Personally, I would hire this done. If you get your stucco wrong you're in for a world of hurt (and cracks!). You can also use Lime Plaster which is a breathable coating, but may need up to 5 coats, and may possibly let in too much moisture. But if stucco gets a crack, which it will inevitably get, it will let moisture in. I'm thinking of going with the lime plaster, (we get a fair amount of rain here in the Bay Area) but I have reservations about both. Good luck!! I would definitely recomend checking out books on this - pictures really help!