Tuesday 23 June 2020

Dry heath

It's a biome! Dry heath is an intermediate stage in ecological succession; where well-drained soil is paused in its journey to becoming a real grown-up forest. This adolescence may be extended for decades if someone runs a bunch of sheep across the landscape and they nibble nibble to scarf up any wannabe trees before they become saplings. The Red Hill, for which our townland is named, is 200 ha. in extent and owned in common by ~20 shareholders. The Department of Agriculture and their puppet-masters in Brussels are interested in doing something different and potentially more productive with Ireland's uplands. On their watch, the foolish application of policies and subsidies has seen the wholesale degradation of the habitat by undergrazing; overgrazing, poaching, soil-erosion; monoculture forestry with invasive species; turf-cutting, not turf-cutting; heather burning. Last year we-the-commoners became part of a pilot study to investigate other uses for the hill than running lean-and-hangry, almost feral, yellow-eyed monsters of the species Ovis aries. Pilot studies are too often driven by haven't-a-clue policy-makers; I suppose, in fairness if they had a clue, it wouldn't need a pilot study.

Whatevs, like. The upshot is that we are now well into our second year of drawing down money from The Man and so, maybe, are in a position to see if anything we did last year has had any impact on The Hill and/or the thinking at head office. I used to share a house with two long-haired botanists (and their long-haired cat) and let's say I was glad I never had to sleep on the dander sofa. But they were super-sound interesting blokes despite having been born across the water.  Project Repurpose has hired another exemplar of the Type, as The Ecologist. And last Saturday a couple of us went for a yomp up and round the hill with Tom the Plant to record the presence / absence of key species on the dry heath. So it was qualitative rather than quantitative research.

Dry heath is increasingly rare in Western Europe and nobody wants to see the last few patches of the stuff disappear under shopping-malls or hundreds of hectares of Sitka spruce Picea sitchensis. There are (at least) three sources of concern:
  • Succession, especially if the replacing trees are foreigners like Sitka spruce and Christmas tree Abies procera. A few hawthorn Crataegus monogyna, black-thorn Prunus spinosa, hazel Corylus avellana and willow Salix spp. can be tolerated for shelter and hedging. And native birch Betula pubescens because it is so pretty.
  • Bracken Pteridium aquilinum: unforgiving competitor for light and nutrients during the Summer. Dangerous in July when they produce carcinogenic spores. Full of toxic secondary compounds, so it's a good thing that sheep refuse to eat the stuff.
  • Too much spiny gorse Ulex europaeus which can grow to impenetrable thickets, excluding or entangling sheep and forming a potential fire-hazard. Small quantities tolerated for day-brightening coconutty blossom and as a source of kindling
This [above looking southeast towards the plains of Wexford] is what we found.
  • The three heathers [all you need to know about the blooming heather, go lassie go]
    • Erica cinerea Bell Heather Fraoch Cloigíneach 
    • Erica tetralix Cross-leaved Heath Fraoch Naoscaí 
    • Calluna vulgaris Ling Fraoch Mór 
  • Other shrubberies
    • Ulex gallii Western gorse native to Ireland desirable indicator species
    • Ulex europaeus Whin/Gorse/Furze/Bushes invasive in blow
    • Vaccinium myrtillus blueberry/bilberry Fraochán [prev] 100 years ago the fraocháns was a big money-spinner for cash-poor families in the Blackstairs - read the book.
  • Sedges
    • Trichophorum cespitosum deergrass  Cíb cheanngheal 
    • Eriophorum angustifolium Cottongrass Ceannbhán
    • Schoenus nigricans Black Bog-rush Sifín
  • Forbs
    • Galium saxatile heath bedstraw Luibh na bhfear gonta [wounded man's herb for its supposed antiseptic qualities]
    • Potentilla erecta tormentil Néalfartach 
    • Stellaria holostea stitchwort Tursarraing mhór
    • Hyacinthoides non-scripta bluebell Coinnle corra [prev]
    • Pedicularis sylvatica lousewort Lus an ghiolla
    • Oxalis acetosella wood sorrel Seamsóg [prev]
    • Polygala serpyllifolia heath milkwort Na deirfiúríní
Tom the Plant needed to record at least 10 of a short list of species indicative / diagnostic of dry heath. He was 9 out of 10 within 500m and 40 minutes of opening the mountain gate, so that ticked the boxes. But he confessed to getting a proper education in the Blackstairs project because every commonage was different and everyone was good. And while identifying and preserving "dry heath" habitat had been a significant driver of the funding, "dry heath" was as hard to grasp and tie down as running water. All that book-l'arnin' was grand but the reality on the side of a blustery south-facing hillside in SE Ireland made for a lot of exceptions. Then again, those names put on biomes do have a predictive quality: if you find tormentil hugging the ground near a bunch of heather you'll be able to make money betting to find heath bedstraw within 5m.

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