This spring I've grown out a couple of selections of F4 yellow snow peas. I should probably go through the development of these lines, if only to remind my self of what went on.
These were originally grown as a bit of an afterthought along a marginal dry bed next to a half shaded fence. I had returned from a lengthy winter holiday to find a mass of F1 plants with set pods, but because of weather conditions, some of the pods had sprouted or sprouting seeds in them. I just chucked a whole heap of what I thought were ruined seeds into a bed, and got a great germination. The plants struggled, many only setting one or two weak pods, so selection was a bit difficult, but two plants stood out, with big pods, and vigour.
I bulk collected the yellows, and individually bagged the good plants, and grew them out.