More on Swiss Chard sprouts

After a little digging around, I came across this swiss chard page on growingtaste.com.

A chard "seed" is actually a cluster of seeds in a dried fruit: often, several seedlings will grow from each fruit; hand-thinning is almost always necessary (and important). Chard is notoriously slow to germinate, so the seedlings may emerge over a relatively long period of time, making a stand of different sizes and ages of seedlings.

So, there it is. when the seedlings are another half inch or so, I'll have to thin.