On 3rd September 2017, I was undertaking a long-overdue clearance of the ‘weeds’ dominating a bed of leeks in my vegetable patch, if only to salvage something of the crop. Prominent amongst them were three members of the dead-nettle family Lamiaceae, thankfully all annuals, unlike many of my other invaders.
The smallest, red dead-nettle Lamium purpureum, is very familiar to me, with its often purplish shoots and stalked, rather round-toothed, stem leaves which resemble those that subtend the small, purplish-red flowers.
However, there was also a single plant of a taller relative with rather larger flowers. Its middle and upper leaves lacked stalks and the sepals were covered with close-lying hairs, all of which made it the northern dead-nettle Lamium confertum. This latter species is, as its name suggests, now restricted almost exclusively to Scotland. It has turned up in Assynt, so far, just three times, at Clachtoll (potato patch, 1997), Clashmore (garden, see picture taken 14th October 2014), and in my garden at Nedd, where I noticed it first in August 2015.
Most conspicuous of the three, at well over a foot tall, were two sprawling plants of another, slightly more distant relative, covered with rigid, bristly hairs, which I recognised as one of the hemp-nettles Galeopsis spp. Two species occur in Assynt, the common hemp-nettle G. tetrahit, which was described in the Flora of Assynt as ‘an uncommon weed of gardens and disturbed ground’ and the bifid hemp-nettle G. bifida, which was recorded locally for the first time in 1995, in the garden at Kerrachar.
A close look at the flowers (see photograph taken down microscope) revealed a purplish-red lip with the pigment extending right to the recurved sides and a marked notch at its end. This identified it without doubt as the second, rarer species G. bifida. I first noted it at Nedd last September, when a single plant turned up, and I have spared one of the plants this year to see if it occurs again. Were it much larger, it would surely qualify as a most attractive flower, but size and circumstances are against it.
Many of these ‘weeds’ were probably much commoner in the past, when much more croft ground was cultivated. The recent occurrences at Nedd may reflect my somewhat relaxed attitude towards weeding, but it is still a puzzle where they have come from.
Ian M. Evans