hau, Starr,
Desert atmosphere and mulch sound like they go together but there is a genuine concern here.
Sweet corn stalks are great harbors for several diseases, corn blight, sweet corn rust, smut, Stewart's disease, maize dwarf mosaic disease and maize white line mosaic disease.
Complete drying of stalks does not get rid of any of these diseases and can infact help their spread.
This makes it better for hot composting than for mulching.
Hot composting can kill the spores as long as the internal temp gets up to 160 f.
Mulch does not have to be organic, plant material. It does need to be opaque, which will block sunlight, one of the main functions of mulch.
I have used old clothes, cardboard, wood chips,
compost, even chewed up old tires can make a good mulch.
While it is preferable to use organic materials for this purpose, since they will decompose and enrich the soil they protect.
In a Desert climate, other materials may be preferable from both an availability and practicality basis.
The Lasagna mulching technique is also worth considering, especially if you can get hold of finished hot method compost and cardboard.
In the Desert, wind would also need to be considered since you would not want your mulch to be blown away to the sand dunes.