plant walks and talks (2018-2019) - course notes ......talk in scout and guide hut (may 9). seymour...
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Plant Walks and Talks (2018-2019) - course notes
Course leader: Alan Hamilton 01483 414597, 07593812715
Meeting places and times
Meet at 10.00 at the places below (except for the walk on June 27, which will start at 11.00).
Make your own way to the starting points, using car sharing as possible. Each event lasts
about 2 hours, except the last, which will be followed by a picnic (bring you own food and
drink) and (in the afternoon if your wish) a visit to see the house of Gilbert White at
Selbourne (you will have to pay your own entrance fee).
Bunmore Copse (May 2). To see bluebell wood and spring flowers. Meet opposite Withies
Pub, Compton, 10 a.m. SU965468. Take A3100 Godalming to Guildford road, turn left at
roundabout down B3000 towards Compton. Withies Pub is down a road on right after 1.5
miles. Park opposite pub.
Talk in Scout and Guide Hut (May 9). Seymour Road, Godalming. SU957434. Meet 10 a.m.
Go towards Milford from Godalming. After the railway bridge after the Inn on the Lake, turn
right up Eashing Lane. Seymour Road is on the left at the top of the hill. The Scout and Guide
hut is opposite Green Oak Primary School. Please come to this talk with a few specimens of
plants with flowers plus stems and leaves attached - we will be looking at these specimens
to learn about plant identification. Please also bring a flora (book used for identifying the
plants) if you have one.
If there are a lot of participants in this course, the group will be divided into two for all
except the last field trip. Those who are able will be requested to come on the Friday
following the Thursday. This will not apply to the last event - everyone who wants to
come should come on the Thursday:
Hankley Common (May 16 and possibly 17). To see heathland (on Lower Greensand). Meet
Hankley Common Car Park, 10 a.m. SU890411. Go to Elstead, turn left along Thursley Rd
after Woolpack Inn. After 3 miles, road turns sharp right, then sharp left. Go straight on at
the second turn down a dirt track. Car park is on left at top of hill after 1 mile.
Ebernoe Common (May 23 and possibly 24). Ancient woodland and species-rich grassland
on Gault Clay. Meeting place: car park of Ebernoe Church, 10 a.m. SU975278. From Milford,
take A283 towards Petworh. After Northchapel and turning to the right to Lurgashall, take
next turning left (Streel’s Lane). Streel’s Lane bends sharply to the left and then sharply to
the right. About ¾ after the sharp right-hand bend, there is a track to the right leading to
Ebernoe Church.
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Farncombe Boat House (June 6 and possibly 7). Riverside and floodplain plants. SU981445.
Meet on river bank opposite the boat house, 10 a.m.
Sheepleas (June 13 and possibly 14). Chalk grassland and woodland. Meet Sheepleas Shere
Road Car Park, 10 a.m. TQ085515. Nearest postcode KT24 6EP. The easiest way to get there
is go up the A246 from Guildford towards Leatherhead. After Hatchlands Park (on left), turn
right at roundabout (Sheepleas is signposted). The car park is on the left (a little hidden)
inside a wood.
Box Hill (June 20 and possibly 21). Chalk grassland and woodland. Meet in car park
opposite visitor centre at top of Zigzag Road, 10 a.m. Note there is a parking charge for non-
National Trust members (last year £3 for 2 hour). To get there: Take A25, go past Dorking,
turn left onto A 24. Turn right at 2nd roundabout (signed ‘Box Hill’). Turn right off this road
(signed ‘Box Hill’) and go up ZigZag Road to top of hill and park in the car park opposite the
NT visitor centre.
Noar Hill (June 27 – everyone who wants to come should come on this Thursday – there
will not be a Friday trip). Chalk grassland and scrub, followed by a visit to the Gilbert
White Museum. Meet by side of lane near Noar Hill, 11 a.m. SU738323. To get there: go
down A3, turn right at roundabout on B3006 towards Selbourne. Just before Selbourne, turn
sharp left just after Ketcher’s Farm (which is on the right) on lane towards East Tisted. Take
first turning left and park by side of the lane taking care not to obstruct the lane (large farm
machinery may pass). Remember to bring a packed lunch and a drink if you want to stay for
a picnic. We will have a visit to the Gilbert White Museum after lunch. Entrance fee
(concession) £9.
Turn left just
before Selbourne
Turn left &
park by side
of lane. DO
NOT
OBSTRUCT
THE LANE Coming from A3
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The main groups of plants are as follows:
Pants are a group of organisms able to capture energy from the sun, using it to create living
matter from non-living materials.
Lower (or non-vascular) plants
Bryophytes (hornworts, liverworts and mosses)
Higher (or vascular) plants
Pteridophytes (horsetails, ferns and clubmosses)
Seed plants
Gymnosperms (conifers, ginkgo, cycads)
Angiosperms (flowering plants)
Monocotyledons (having one seed leaf)
Dicotyledons (having two seeds leaves)
Life forms of plants. Some commonly recognised are trees, shrubs, herbs, climbers,
scramblers, epiphytes, parasites.
Evolution of land plants
All land plants are descended from a common ancestor (green algae) that lived nearly 500
million years ago.
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Recognising plants by their vegetative characteristics, e.g. leaves of British
trees (NB Turkey oak, Red oak and Sweet chestnut are not native)
Quercus petraea
(Sessile oak) Quercus rubra
(Red oak - American)
Quercus cerris
(Turkey oak - central
to SE Europe) Quercus robur
(English oak)
Corylus avellana
(Hazel)
Ulmus procera
(English elm) Ulmus glabra
(Wych elm)
Carpinus betulus
(Hornbeam)
Alnus glutinosa
(Alder) Tilia platyphyllos
(Large-leaved lime)
Fagus sylvatica
(Beech)
Populus tremula
(Aspen)
Betula pendula
(Silver birch)
Salix caprea
(Goat willow)
Salix alba
(White willow) Castanea sativa
(Sweet chestnut)
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Parts of the flower Apetalae: (hazel – wind-pollinated)
Monocotyledon flower (flowering rush
– 3 sepals and petals) Dicotyledon flower (Geranium
– 5 sepals and petals)
Zygomorphic flower with
joined petals (foxglove)
Inferior ovary (snowdrop)
Illustrations to show variations in flower structure in flowering plants
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Geology and soils of the Godalming area
Solid geology. There are three main formations in the Godalming area, all of Cretaceous
Age (145-66 million years ago). This is the last phase of the age of the dinosaurs (which
became extinct 66 million years ago – apart from the brids – as a result of environmental
changes caused by the impact of a huge meteor falling near Mexico). The date of 145 million
years ago marks about the time when the first flowering plants (Angiosperms) appeared. By
66 million years ago most of the plant families with which we are familiar had appeared.
Chalk (100-66 million years old). This is a soft calcareous rock formed from
sediment that was deposited in a warm shallow sea. Much of the chalk
consists of microscopic plates of green planktonic algae known as
coccolithophores (left). Flint nodules (chemically silicon dioxide) occur in the
flint. The Chalk gives rise to alkaline soils. Chalk grassland is the most species-rich type of
vegetation found in Britain.
Lower Greensand (126-113 million years old) typically consists of unconsolidated sandstone
originally deposited in a near-shore marine environment. In places, the Lower Greensand is
enriched with lime (giving rise to more alkaline soils) or consolidated (Bargate stone in
Godalming). Soils formed from Lower Greensand are typically acidic.
Weald Clay (136-125 million years old) is a blue-grey mudstone which turns yellow and very
sticky when wet. It forms a heavy soil liable to water logging with rain.
Godalming
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Superficial deposits. These include clay with flints, a thin deposit found in many, more
level, places on more level areas of the chalk. The soils are not calcareous. Alluvium occurs
in valley bottoms. Much of this was deposited after clearance of forest for agriculture in
prehistoric times. The greensand is readily eroded if left exposed or where there are paths
or tracks, resulting in spreads of redeposited material downslope.
Processes causing change to the flora and habitats
The life cycles of plants. Seed > seedling > young plants
> mature plant, reproducing > old age > death. For
example, ling heather (Calluna vulgaris), the dominant
plant in heathlands, has four main stages: (1) pioneer
(0-5/6 years) – seedling development and
establishment until the plant has developed into a
fully-formed bush; heather cover is small and other
species of vascular plants reach their maximum
abundance, also mosses and lichens; (2) building (up to
15 years old) - excludes all other flowering plants; (3)
mature; (4) degenerate (after ca 30 years) - active
growth declines, canopy opens and exposes more ground, bryophytes reach their maximum
abundance and other species of plants are able to become established.
Vegetation succession. This is the sequence of species and vegetation types that can
naturally replace one another with the passage of time. One common change is for shorter
types of vegetation to become replaced by taller ones, as short species are replaced by tall
ones, winning the battle for light. The picture is for succession in North Carolina, taking
about 100 years to go from the pioneer phase, through various intermediate vegetation
types to the climax community (which then remains, but still changes internally as individual
plants die and are replaced in their positions by others).
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Arrival of new species and disappearance of
others. A recent example has been the arrival
and spread of the fungus that causes ash
dieback (dying ash pictured right).
Extinctions are evolution of new species.
Pictured right: life in the last interglacial in
Britain (130,000-113,000 years ago). The
climate was a little warmer than today, but the
natural vegetation was broadly the same as in
the present warm phase – the postglacial
period, which began ca. 10,000 years ago).
Trees included oak, elm, alder, etc.. The fauna
broadly included modern species of animals,
plus auroch and some (perhaps surprising)
additions – lion, straight-tusked elephant,
hippo, an extinct rhinoceros.
Changes in the physical environment. For example: soils, and climate.
Changing using of the land. Left - native forest (Epping Forest). Right - Douglas fir
plantation.
It is not only changing use of the land that is
relevant to the look of the landscape here, but
throughout the world, now we are an
interconnected global economic system. Pictured
right: greenhouses in Almeria. In extreme south-
east Spain - the home of spaghetti westerns. Many
British supermarkets now get lettuce and tomatoes
here.
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Ecostages: Wild plants and their habitats around Godalming in wider temporal and spatial contexts (GHP = global human population) ECOSTAGE ECONOMY CULTURE NEWCOMERS TO THE BRITISH FLORA
(& pests and diseases) HABITATS & LANDSCAPE
(related to production and use of biological resources) (around Godalming)
Globalisation accelerating. GHP reaches 7,700,000,000 (2018 AD)
Intensive industrialised farming & ‘scientific’ forestry. Widespread decoupling of places of production and use of resources. Many people high consumers of resources
Decline in widespread detailed knowledge of local nature. Reality of global ecosystem realised, rise in environmentalism
Mass imports of plants and plant-based products. Some serious pests & diseases introduced: virulent strain of Dutch Elm Disease (1960s), Sudden Oak Death (2003), Ash Dieback (2012).
Industrial farming & forestry result in extensive loss & fragmentation of semi-natural habitats (meadows, ancient woodland, heathland). Pollutants influence flora (global warming, acid rain). Establishment of Nature Conservancy (1949). Competition for land use (food production, nature, housing)
1950 AD: PROPOSED DATE FOR START OF ANTHROPOCENE. Global marker: radioactivity from nuclear tests detectable worldwide
Rise and spread of ‘the West’. GHP reaches 2,500,000,000 (1950)
European trading networks expand & become global. Industrialisation Revolution. Growing reliance on fossil fuel
Transformation of Europe economically & culturally, coming to influence everywhere else. Rise of science & natural history. National parks
Global exploration leads to many introductions to British gardens, for forestry, etc. Introduced invasive include: sycamore (1500), Turkey oak (1735), Himalayan balsam (1839), Japanese knotweed (1800s)
Peak of iron-smelting industry using charcoal in the Weald (1500-1650). Agricultural revolution from ca. 1700 (enclosed fields, hedges, liming, crop rotation). Establishment of Forestry Commission (1919); forest area expands
1500 AD: NEOPHYTE/PALAEOPHYTE BOUNDARY FOR INTRODUCED SPECIES. WOODLANDS PRESENT BY 1600 AD CONSIDERED AS ‘ANCIENT’
Subsistence production. GHP reaches 500,000,000 billion (1500 AD)
As before, but with production added (crops & livestock). Later: more intensive agriculture (e.g. irrigated), pre-industrial states & more trade
As before, but with rituals and ceremonies added to ensure the harvest. Later, invention of writing, information diffusion & xxx
Introductions of crops (earliest included wheat, barley & peas), plus other plants (including weeds)
Farmland expands. People influence abundances of tree species. Woodmanship practiced. Faunal extinctions: bison 3000 BC, auroch 1000 BC, wild boar 1400 AD, beaver 1500 AD. Heathlands developing from 2500 BC
FROM 4300 BC (in Britain) : ADOPTION OF AGRICULTURE: PROPOSED OF ANTHROPOCENE (earliest 9500 BC in Middle East)
Wild produce harvesting. GHP reaches 5 million (10,000 BC)
Dependency on local wild bioresources through gathering, hunting & fishing. Mesolithic people in woodland habitat. Palaeolithic people in earlier times
Many people very knowledgeable about local bioresources. Close connections perceived between natural, human & spiritual worlds
Temperate flora enters from south after end of ice age: pine 8500 BC, then oak, lime 7300 BC. Land bridge to continental Europe broken 5600 BC
The wildwood develops from 8500 BC from previous tundra-like conditions. Soil maturation. People probably had some influence on the wildwood (e.g. burning for hunting purposes)