I sowed about 100 (3 flats worth) of A. Palmatum seeds. For the most part the seedlings have two true sets of leaves. Some of the seed came from friends with cultivated varities, some from a wholesaler. 4 seedlings, which I have labeled "atro" are variegated. Obviously, I realize that you need to grow them for 2 or 3 years to see what their leaves will relaibly look like, but I was just wondering how often you get variegated seedlings randomly like this. None of the seed came from a variegated parent.
Some snakebark maples may yield quite a few. However, getting them to grow up into thrifty trees that remain variegated is not always so easy. You may find that your few variegated Japanese maples may not amount to anything either. Some variegated Japanese maple seedlings (or branch sports?) have made good plants, of course, as there are multiple variegated cultivars.
Quite frequently a seed from a hybrid will not come 'true' when planted. You can end up with any of those plants which were 'hybridized' to get that one from which you obtained the seed.