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Plants of the Limestone Barrens A Presentation by John Maunder Curator Emeritus of Natural History The Rooms Provincial Museum of Newfoundland and Labrador The Limestone Barrens Habitat Stewardship Program Conservation and Sustainable Ecotourism Conference Plum Point, Newfoundland October 12-13, 2006 Plants? … What plants? … Cape Norman At first glance, there’s almost nothing there! Burnt Cape [photo: Pat Montegue] But, when you begin to look more closely … Watt’s Point … usually MUCH more closely…. Watt’s Point Flowers Cove You’ll see an amazing garden of botanical treasures! Redtipped Lousewort - Pedicularis flammea – Big Brook Some quite spectacular … Glacier Sedge – Carex glacialis – Boat Harbour Others pretty dull … But, what’s all the fuss about? Alpine Ragwort - Packera pauciflora – L’Anse aux Meadows Dwarf Hawk’s Beard – Crepis nana – Burnt Cape What makes these plants so special? Aren’t they just like plants from other places? Common Dandelion – Taraxacum officinale – Raleigh Well … some are … Northern Anemone - Anemone parviflora – Burnt Cape But most aren’t …It’s all a bit complicated Our limestone barrens species fall into about 5 special categories … … grouped by their general distribution near Eddies Cove West 1. Newfoundland Endemic “Limestone-Loving” Species Species found only in Newfoundland, in the whole world! Barrens Willow – Salix jejuna – Cape Norman Fernald’s Braya – Braya fernaldii – Big Brook and Watt’s Point Long’s Braya – Braya longii Sandy Cove and Yankee Point … and, MAYBE? “Burnt Cape Cinquefoil” Potentilla usticapensis … [or Potentilla pulchella var. pulchella] … There are varying taxonomic interpretations … so its endemic status is uncertain Burnt Cape 2. Gulf of St. Lawrence Endemic “Limestone-Loving” Species Species found only in the Gulf of St. Lawrence region (which includes the Newfoundland west coast and Strait of Belle Isle), in the whole world! St. Lawrence Primrose – Primula laurentiana – Raleigh Newfoundland Pussytoes – Antennaria eucosma Cape St. George Longleaf Arnica – Arnica lonchophylla – Humber Gorge 3. Disjunct “Limestone-Loving” Species Species found both in some far-away place, AND in our area, with a BIG GAP in between. Dwarf Hawk’s Beard – Crepis nana – Burnt Cape …. Disjunct to N tip of Labrador, and arctic and western North America Newfoundland Orchid – Pseudorchis albida subsp. straminea Burnt Cape - Disjunct to Greenland and one locality in Hudson Bay Woolly Arnica – Arnica angustifolia subsp. tomentosa – Point Riche Peninsula … Disjunct to mountains of northwestern North America [photo: Rene Charest] Pendantpod Oxytrope - Oxytropis deflexa var. foliosa – disjunct [from S Labrador] to N tip of Labrador, Gaspe, Hudson Bay, and low arctic and western North America Bodin’s Milkvetch – Astragalus bodinii – Cook’s Harbour … disjunct to western North America 4. More Widespread “Limestone-Loving” Species Calypso Orchid - Calypso bulbosa var. americana – Burnt Cape Yellow Ladyslipper – Cypripedium parviflorum var. pubescens – Port au Choix Small Roundleaf Orchis - Amerorchis rotundifolia – Burnt Cape Frog Orchid – Dactylorhiza viridis Killdevil Mountain [photo: M. Anions] and Burnt Cape Purple Mountain Saxifrage – Saxifraga oppositifolia – Table Mountain Tufted Saxifrage - Saxifraga cespitosa – Old Port au Choix Island Gentian – Gentianopsis nesophila – St. John Bay Alpine Chickweed – Cerastium alpinum subsp. lanatum – Lower Cove White Mountain Avens – Dryas integrifolia Sandy Cove [photo: N. Djan-Chekar] and Flowers Cove [photo: Pat Montague] Yellow Mountain Saxifrage – Saxifraga aizoides – Eddies Cove West Alpine Bearberry - Arctous alpina – L’Anse-au-Loup Newfoundland Oxytrope – Oxytropis campestris var. minor – Mount Parent, P.Q. Elegant Milkvetch - Astragalus eucosmus – L’Anse aux Meadows Hairy Willow - Salix vestita – Port au Choix 5. Widespread Species which are not “Limestone Loving” They’ll grow almost anywhere! Larch – Larix laricina – Big Brook White Spruce – Picea glauca – Table Head [photo: Pat Montague] Living on the limestone barrens can be quite a challenge! How do the plants manage it? Trailing Juniper - Juniperus horizontalis – Port au Choix [photo: Pat Montague] What conditions do they have to overcome? Alpine Pussytoes – Antennaria alpina subsp. canescens – Watt’s Point Many, it seems! It is really useful to understand what makes barrens of ANY type, “barrens”. Cape Norman The first challenge is DRYNESS … even in areas that receive a lot of moisture Burnt Cape [photo: Pat Montague] Wind is usually the critical factor … especially in winter. It’s not hard to tell how deep the sheltering snow gets in this area! Eddies Cove Trailing Juniper – Juniperus horizontalis – Port au Choix [photo: Pat Montegue] Even in summer, it helps to have a low profile to stay out of the drying wind, and within the thin, sun-warmed, surface air layer Dwarf Hawk’s Beard – Crepis nana – Burnt Cape Tight cushion architecture can conserve a core of dampness within the cushion Flowers Cove, “White Rocks” Some plants find other ways to stay out of the wind Laurentian Fragile Fern – Cystopteris laurentiana – Flowers Cove “White Rocks” Other plants just grow smaller in exposed areas [while usually preserving flower size!] Greenland Primrose – Primula egaliksensis – Cook’s Harbour and Boat Harbour Rand’s Eyebright - Euphrasia randii – Cape St. Francis Hair creates a layer of dead air against the plant surface to help slow moisture loss when the plant’s pores are open Netvein Willow – Salix reticulata – Lower Cove Waxy and leathery surfaces help slow water loss from the surface Reddish Sandwort - Minuartia rubella – Port Saunders Narrow leaves with less leaf surface area lose less water The second challenge of the barrens is COLD. However, cold is only partly a winter concern. For most arctic and alpine plants, once the temperature has dropped below a certain point, cold is just cold W of Red Bay, Labrador, July 12, 2001 The main thing affected by cold is the total length of the growing season … L’Anse-Amour, Labrador This photo was taken July 8 – and the willows are still just in early bud! Moss Campion – Silene acaulis – Burnt Cape Tight cushion architecture allows for a layer of “dead air”, within the cushion, that can warm up and stay warm all day Cold also leads to frost disturbance …. Watt’s Point … seen most dramatically in patterned ground Burnt Cape [photo: Pat Montague Daubenmire (1941) tap roots anchor plants deeply into the seasonallydisturbed frost-heaved soils This rare species, the Cutleaf Fleabane, grows in Humber Gorge Long’s Braya – Braya longii – Yankee Point Some roots are contractile ... each time a plant is heaved upward by frost, the root of the affected plant shortens to pull the plant back down into the soil, where it belongs. The third challenge of the barrens is obtaining sufficient NUTRIENTS. Barrens usually occur on thin, poor soils. Boat Harbour The THINNESS of the soil is largely the result of ice-age glacial scouring … Glacial Striae – Hawkes Bay Cape Norman … and subsequent wind and water erosion. Cape Norman The POORNESS of the soil is usually the result of its basic geology, or of its history of poor organic accumulation in places where vegetation has long been sparse. Cape Norman But even here, plants manage to grow … Barrens Willow - Salix jejuna - Cape Norman In general, precipitation tends to run off quickly … or just drain away, downwards, through the substrate … carrying unconsolidated nutrients with it. Port au Choix Oval-leaf Spearwort – Ranunculus flammula var. ovalis – Port au Choix Even so, some species, like this buttercup, seem to need such changing conditions! Arctic Bladderpod - Lesquerella arctica – Burnt Cape As you have already seen, plants of the barrens have all kinds of survival tricks Moss Campion – Silene acaulis Daubenmire (1941) LONG ROOT SYSTEMS are critical in accessing scarce moisture and nutrients from a very wide area of soil EVERGREEN LEAVES conserve hard-won and costly resources that would otherwise be lost, and have to be regenerated every year … Hollyfern - Polystichum lonchitis – Burnt Cape ….and, as long as evergreen plants stays relatively green throughout the year, photosynthesis can take place, on warm days, in any season, effectively lengthening the plant’s growing season Trailing Juniper – Juniperus horizontalis – Port au Choix In the limestone barrens, the chemistry of calcium adds to the challenge Encrusted Saxifrage - Saxifraga paniculata – Burnt Cape This saxifrage secretes excess lime from the edges of its leaves A major advantage of living on the barrens – is a lack of competition! Dwarf Hawk’s Beard – Crepis nana – Burnt Cape Many barrens species, such as Long’s Braya, actually thrive in disturbed areas where nothing else tends to grow Yankee Point But, in general, the plants of the barrens live on a razor’s edge Burnt Cape Alpine Milkvetch – Astragalus alpinus var. alpinus – Burnt Cape … with the rarer ones just making it … Balsam Ragwort – Packera paupercula var. balsamitae – Indian River … and some others doing much better … But, we really don’t know what’s ahead for them Peter Scott … will climate change help Long’s Braya … but hinder Fernald’s Braya? … or vice-versa? … or neither! We might guess … but we really don’t know. Will humans and nature eventually find ways happily co-exist? It would be nice! One thing is for sure … Even as tourists arrive in increasing numbers … Cape Norman … and humans in general continue to expand their influence Heavy equipment re-arranging the Romaines River floodplain, August 1, 2006 ! We still have much to learn Boat Harbour … any many discoveries to make! … End Crab Spider on Yellow Lady Slipper – Burnt Cape