You are correct - the photo you posted is ash with a curly maple top. Alder does not take dye or stain well, but you can use orange pigment or Transtint dye to make an orange toner (tinted clearcoat) and spray that instead of dyeing the or staining the wood. Alternatively, you could use a wood conditioner -- which is basically a very thin shellac or other finish - to diminish the likelihood of blotching. But I'd go with a toner to stay on the safe side.