introductiontothemanagementofgrasslandandwetlandhabitats...

3
Introduction to the management of Grassland and Wetland habitats Mark Webster 14/9/15 Pott Row Village Hall for GVCG A Summary of presentation with additional reference to The History of the Countryside Oliver Rackham 1986 J.M.Dent; Fens, Bogs and Marshes: their flowers and vegetation a presentation at Wicken Fen by Owen Mountford 2015; http://www.wildlifetrusts.org/wildlife/habitats/lowlandmeadows Meadow is Grassland created by cutting or Mowing by humans for hay. Pasture is grassland grazed by Farm animals. Trees are the natural vegetation in our latitude round most of the world. Grassland occurs in places that are too dry or too high for trees or are grazed too much by wild animals. Pollen studies suggest grassland was rare before civilization. The landscape appeared to transform to grassland beginning with the arrival of Neolithic man in 4000 BC. Meadows and pastures though now a welldefined plant communities appear to have assembled together from a selection of plants that once grew in places too high or too far north for the wild wood. Meadows tend to grow on fairly neutral soils. Acidsandy soils tend to become a heathland population. Pasture is often wet marshy grassland or fen and tends to be acid and chalk grassland. Grazing farm animals on pastures are often sheep goats and Highland cattle. Churchyards are sometimes the best piece of ancient grassland in any locality Broadly there are 3 types of meadow. Unimproved or nutrient poor or nonfertilized; is best or the most bio diverse and is dominated by thinner grasses which allow other herb species to coexist. Less than 15,000 hectares of unimproved neutral grassland remains in the UK

Upload: others

Post on 31-May-2020

4 views

Category:

Documents


0 download

TRANSCRIPT

Page 1: IntroductiontothemanagementofGrasslandandWetlandhabitats ...btckstorage.blob.core.windows.net/site13320... · • InappropriateManagement"includes"over"mowing,toppingand"not"removing"the"cuttings,"

Introduction  to  the  management  of  Grassland  and  Wetland  habitats  

Mark  Webster  14/9/15  Pott  Row  Village  Hall  for  GVCG  

A  Summary  of  presentation  with  additional  reference  to  The  History  of  the  Countryside  Oliver  Rackham  1986  J.M.Dent;  Fens,  Bogs  and  Marshes:  their  flowers  and  vegetation  a  presentation  at  Wicken  Fen  by  Owen  Mountford  2015;  http://www.wildlifetrusts.org/wildlife/habitats/lowland-­‐meadows  

Meadow  is  Grassland  created  by  cutting  or  Mowing  by  humans  for  hay.  

Pasture  is  grassland  grazed  by  Farm  animals.  

Trees  are  the  natural  vegetation  in  our  latitude  round  most  of  the  world.    Grassland  occurs  in  places  that  are  too  dry  or  too  high  for  trees  or  are  grazed  too  much  by  wild  animals.  Pollen  studies  suggest  grassland  was  rare  before  civilization.    The  landscape  appeared  to  transform  to  grassland  beginning  with  the  arrival  of  Neolithic  man  in  4000  BC.    Meadows  and  pastures  though  now  a  well-­‐defined  plant  communities  appear  to  have  assembled  together  from  a  selection  of  plants  that  once  grew  in  places  too  high  or  too  far  north  for  the  wild  wood.  

Meadows  tend  to  grow  on  fairly  neutral  soils.  Acid-­‐sandy  soils  tend  to  become  a  heathland  population.    Pasture  is  often  wet  marshy  grassland  or  fen  and  tends  to  be  acid  and  chalk  grassland.    Grazing  farm  animals  on  pastures  are  often  sheep  goats  and  Highland  cattle.      

 

Churchyards  are  sometimes  the  best  piece  of  ancient  grassland  in  any  locality    

Broadly  there  are  3  types  of  meadow.    

• Unimproved  or  nutrient  poor  or  non-­‐fertilized;  is  best  or  the  most  bio  diverse  and  is  dominated  by  thinner  grasses  which  allow  other  herb  species  to  coexist.  Less  than  15,000  hectares  of  unimproved  neutral  grassland  remains  in  the  UK  

Page 2: IntroductiontothemanagementofGrasslandandWetlandhabitats ...btckstorage.blob.core.windows.net/site13320... · • InappropriateManagement"includes"over"mowing,toppingand"not"removing"the"cuttings,"

• Semi-­‐  improved  meadow  Semi-­‐improved  grasslands  still  retain  a  good  number  of  grasses  and  valuable  wildflowers  such  as  Red  Clover,  Bird's-­‐foot  Trefoil,  Ox-­‐eye  Daisy  and  Knapweed  which  are  important  for  Bumblebees  and  many  other  insects.  Under  traditional  management  these  also  have  the  potential  for  supporting  more  species.  

• Improved  or  fertilized  meadow  dominated  by  thicker  grasses  which  tend  to  outcompete  other  species  by  creating  dense  shade.  

Churchyards  are  sometimes  the  best  piece  of  ancient  grassland  in  any  locality  as  they  may  as  old  as  the  oldest  fragment  of  the  church  and  will  often  have  been  grazed  or  mown.    However  even  Churchyard  meadows  can  be  altered  by  too  much  tidiness  or  excessive  mowing.  

There  has  been  a  loss  of  meadows  during  the  twentieth  century.    Up  to  98%  of  lowland  meadows  have  been  lost  since  1945  according  to  the  Countryside  Commission  1984.  This  has  been  caused  by  a  number  of  factors  including  changes  in  farming  practice,  imported  feeds,  silage  and  urbanization.  

Why  manage  meadows?  

In  order  to  hold  back  succession.    For  example  historically  in  the  North  America  prairies  or  pastures  were  maintained  by  the  dry  climate,  grazing  by  large  herds  of  buffalo  and  burning.    Since  the  extermination  of  buffalo  trees  have  advanced  into  the  prairie  land.    Britain  is  too  wet  for  grassland  to  avoid  invasion  without  grazing  or  mowing.      Accordingly  the  habitat  will  succeed  into  woodland.    

Each  part  of  the  UK  boasts  its  own  specialities,  but  the  one  characteristic  shared  by  traditionally  managed  lowland  meadows  is  the  high  number  of  herbs  and  grasses  –  they  can  frequently  boast  up  to  30  grasses  and  100  or  more  wildflower  species.  Grasses  include  quaking-­‐grass,  sweet  vernal-­‐grass,  crested  dog's-­‐tail  and  red  fescue,  while  flowers  include  devil's-­‐bit  Scabious,  pepper  saxifrage,  green-­‐winged  orchid,  snake’s-­‐head  fritillary  and  adder’s-­‐tongue  fern.  In  damper  areas,  cuckooflower,  ragged-­‐Robin  and  yellow  iris  can  be  found,  as  well  as  rarer  species  like  narrow-­‐leaved  water  dropwort.  

 

How  to  manage  meadow?    

In  order  to  maintain  a  meadow  cutting  and  raking  needs  to  be  undertaken.    On  unimproved  meadow  x1  per  year  is  sufficient.    Less  unimproved  meadow  may  require  x  2  cuts  per  year.    The  cutting  is  undertaken  mid  to  late  summer  (Late  June  and  September)  and  the  second  cut  in  early  autumn  (late  September  or  October).    

Cutting  can  be  undertaken  with  a  hand  scythe  or  an  Allen  Scythe  or  reciprocating  mower  which  is  a  toothed  blade  sliding  back  and  forth  horizontally  across  stationary  teeth  to  produce  a  scissor  action,  and  also  drives  two  large  wheels  for  forward  travel.    

In  order  to  render  the  habitat  nutrient  poor  it  is  essential  that  the  cut  vegetation  is  raked  off.    

Problems  Faced  when  managing  meadows.  

These  include:  

• Scrub:  this  includes  a  variety  of  woody  species  such  as  Hawthorn,  Bramble,  Oak  and  Silver  Birch  which  sometimes  grows  very  densely,  shading  out  other  low  growing  herb  or  grass  species.    Scrub  will  mature  into  secondary  woodland  if  left  unmanaged  

• Nettles,  Thistles,  Brambles  and  Ragwort,  invasive  species,  sites  that  have  been  neglected  or  over  managed.      

Page 3: IntroductiontothemanagementofGrasslandandWetlandhabitats ...btckstorage.blob.core.windows.net/site13320... · • InappropriateManagement"includes"over"mowing,toppingand"not"removing"the"cuttings,"

• Inappropriate  Management  includes  over  mowing,  topping  and  not  removing  the  cuttings,  fertilizers,  tree  planning  broad  spectrum  weed  killers,  pond  dredging  and  overgrazing.  

Mark  suggested  avoiding  being  tempted  to  create  meadows  from  scratch.    The  creation  of  meadows  was  dependent  upon  having  poor  soil  in  the  first  place.    However  this  may  be  a  practical  solution  in  urban  settings.    However  it  does  need  ongoing  management  to  ensure  the  new  annual  seeds  have  bare  ground  in  which  to  germinate.    

Wetland  Habitats  

The  word  Fen  is  used  to  mean  different  habitats  in  a  vernacular  (native  language  or  dialect)  sense  but  also  is  used  in  a  scientific  sense.    So  here  is  an  attempt  to  clarify  the  scientific  meanings:  

Expressed  simply    

• a  mire  is  vegetation  on  waterlogged  peat  • A  Bog  is  a  mire  where  Sphagnum  (bog-­‐moss),  Heathers  (ericaceous  shrubs)  and  cotton  grass  

dominate  and  where  the  water  is  acidic.    The  best  example  of  this  locally  is  Roydon  Common.  This  is  unusual  habitat  to  be  found  in  East  Anglia  because  bogs  are  generally  found  in  Northern  and  Western  Britain.    

• A  Fen  is  a  mire  dominated  by  tall  grasses,  sedges,  rushes  and  forbs  where  the  water  may  be  mildly  acidic  but  is  probably  around  neutral  or  even  alkaline.  

 

A  fen  

Reed  beds  require  cutting  every  3  years  and  this  is  generally  undertaken  in  the  winter,  Sedge  beds  in  the  summer.  

KR  15/9/15