Now the leaves have yellowed and are dropping off, revealing a small crop of blackish pods. Presumably the short daylength was enough to arrest their usual vegetative development and initiate flowering and seed formation. Put it another way - I inadvertently tricked them into flowering at the wrong time of year. If nothing else, it's a fairly graphic illustration of how profound the effects of daylength can be on plant development.
It's also made me think about the kind of characteristics I'd like to see in a domesticated talet plant. For our climate we want a plant that makes rapid growth during the early stages of the growing season and then switches over to intensive reproduction in late summer, laying down large quantities of fat seeds for the winter. Realistically, this will need to begin before the equinox, as temperatures and light levels have often fallen too low for acceptable growth after this time and the spectre of an early killing frost frequently stalks the land.
It is apparently the case that yabumame (Amphicarpaea edgeworthii), talet's Asian cousin, shows variation in time of flowering according to latitude; northern latitude plants begin flowering more quickly after sowing and continue for longer than their soft southern counterparts. It's a fair bet that the same is true in the case of Amphicarpaea bracteata. So the hunt is on for northern provenance seeds. This can mean only one thing - Canada.
One particular place in Canada with a climate at least vaguely reminiscent of ours would be a good place to start: Prince Edward Island. Like Anne of Green Gables, whose resolute optimism saw her through the trials of life, I'm positive that another citizen of Canada's 'Garden of the Gulf ' will be able to supply me with some seeds and maybe throw in a tuber or two of Apios americana for good measure. Step forward please.
Other than that, I'd like to see an Amphicarpaea plant that doesn't aspire to be the kudzu of my vegetable patch. All the plants I've grown send out rangy, tentacular shoots and sparse leaves with long flower stalks in their axils. A similar sort of growth habit is common to many other wild beans and is, no doubt, highly adaptive. While hunting for the scattered beans may be OK for wild food afficionados armed with digging sticks, rush baskets and plenty of time, it does rather hamper the gardener's attempts to harvest meal-worthy quantities. It also contributes to the impression that the plant is more trouble than it's worth and should be evicted at the first opportunity. Exit stage left, pursued by a hog.
Leaf spacing is a function of internode length: shorten the distance between leaves and you get leafier, bushier plants with a more manageable habit of growth. Perhaps these plants would, as a result, focus more effort on producing the bit we want, the beans, rather than those serpentine shoots with the insatiable wanderlust. The result? More beans per square metre. As short internodes are produced by recessive genes in other legumes, I suspect the same is true for Amphicarpaea. I have a nagging suspicion that I could be waiting a while for a homozygous bushy plant to appear. Nevertheless, like Anne of Green Gables, or more particularly, Mr Micawber, I'm confident that eventually something will turn up.