Page 40 - ALG Issue 3 2022

readers articles
Moths – an allotment harvest of beauty and interest
Dave Goulson, in ‘Silent Earth’, quotes a Bristol University study finding ‘that allotments had the highest insect diversity of any urban habitat - [...] higher even than city nature reserves’. My partner Sue and I have had an allotment on the outskirts of Chester for three years. When we took over, I began monitoring moths using a light trap, which apart from taking them out of circulation for a few hours, doesn’t harm them at all. I like to think of the moths as an additional harvest; it’s hard to match the vividness of
a Canary-shouldered Thorn or an Elephant Hawk-moth or the intricacy of an Angle Shades. While the summer months bring most moths, there are some to be found throughout the year. That said, I’ve yet to catch any at the allotments in December or January – all my December moths have come in November, for example.
Given how seldom you simply find a moth at rest during the day, it follows that many species must be masters of disguise, deception and concealment. Examples include several of the Quaker
species, which fly in spring and are well camouflaged among last season’s dead leaves. Others, like the Brindled Green, are hard to spot on algae- and lichen-covered branches, while there are several which resemble dead wood, with the Pale Prominent a prime example.
A few moths can be described as ‘allotment specialists’, including several using currant bushes as their larval foodplant; I’ve found two of these, the Spinach and the Currant Clearwing,
on my plot. (Many moth names are descriptive, but as far as I know the spinach has nothing to do with spinach at any stage in its life and nothing makes me think it looks like spinach either). Another currant specialist
is the V-Moth but, though I’ve found
it elsewhere, it has never graced my allotment traps – unsurprising since it has declined massively across the UK, with abundance down by 98% between 1970 and 2016 – if you find it, cherish
it (and inform your local County Moth Recorder).
I’ve found two of these, the Spinach and the Currant Clearwing, on my plot.
Given how seldom you simply find a moth at rest during the day,
it follows that many species must be masters of disguise
Some species certainly feed on our crops; neighbouring plotholders lost tomatoes to Bright-line Brown-eye caterpillars last year; I was happy to see the adults in my trap, but perhaps
I won’t be so pleased if they nibble my fruits in the greenhouse I’m planning to erect soon, and I’ve yet to find out how the Codling Moths will affect the apples I planted last winter. Even if they do, I shan’t be using pesticides to eradicate them, and I’ll take comfort from
the presence of at least one helpful species, the White Plume Moth, whose caterpillars feed on bindweed.
On the Venn diagram of unusual pursuits, there’s certainly some overlap between moth enthusiasts and allotmenteers, so if you want
to explore the mothy biodiversity of your own plot there’s a chance there’s
40 Allotment and Leisure Gardener
I’ll take comfort from the presence of at least one helpful species, the White Plume Moth.