I think I may have given the impression that all my ocas were killed back in October. Actually, that's not strictly true. By happenstance, I had covered up some late-maturing chillies with horticultural fleece. This billowing gossamer drapery offered them sufficient protection throughout the cold period in October, when several hard frosts coincidentally destroyed the flower (literally) of my oca crop. Then, the other night, it did what fleece so often does - it blew away in the gales, exposing the chillies to the frost which followed. I hate those fleeces to pieces!
Still, this gave me an opportunity to take a look at some of the self-sown oca seedlings which had appeared, if not in profusion, then with a surprising frequency amongst the official crop. Conditions were not ideal, what with shade and competition from the chillies. Nevertheless, some of these intrepid interlopers had made a reasonable amount of growth. The frost had put a stop to that, so I decided to take a look at what the situation was on the ground, or rather, below the ground.
It quickly became obvious that the diaphanous polypropylene sheet had done more than offer a refuge to the plants. The friendly neighbourhood voles had been enjoying the warmth and protection provided; with typical microtine gratitude they had launched a preemptive strike on the swelling stolons, severing them before they had a chance to metamorphose into tubers. In some cases they had bitten through the stems of the plants as well. Little piles of julienned tubers were scattered around.
Ah, the perils of stochastic events, the term by which these sorts of randomly fatal happenings are apparently known in population ecology. I notice that Bob Dylan opted to substitute 'stochasticity' with 'a simple twist of fate' in the song of the same title, presumably due to the enhanced lyrical flexibility gained by so doing. Or maybe he don't know much about history, don't know much biology. If you're out there Bob, tell me whether you can throw any light on the four year cyclical variation in vole populations and its effects on my horticultural operations. Might make a good song.
As proof, I offer these pictures of some of my very first self-sown oca plants. Had the frosts held off until this time, as is usual hereabouts, I'm sure they would have done perfectly well without protection.