Plantago lanceolata
is a high pollen producer and its distinctive pollen grains
are wind transported (Sagar & Harper 1964) although to
a slight extent also by insects. The presence of P.
lanceolata in the vegetation is therefore reflected
well in the pollen rain and it can be used as a reliable
indicator species in pollen diagrams. P. lanceolata
is usually interpreted as evidence of the presence of
open areas, waste ground or pasture and so is often associated
with deforestation caused by human activity in the Holocene.
It has been recorded regularly from Late Devensian deposits,
when there would have been many open ground habitiats
dominated by herbaceous communities where it would have
existed. Its pollen has also been recognised in pre-Holocene
interglacials however and so it clearly found suitable
habitats where naturally disturbed soils and vegetation
occurred (Godwin 1975) even during the mid-interglacial
phases of maximum forest development. All interglacials
from the Cromerian (oxygen isotope stage 11) onwards have
records of P. lanceolata pollen, sometimes in high
values. As with the present day, such habitats would occur
beyond the forest zone at altitude or in coastal locations.
Landslides, changes in river courses, fire, storms and
the actions of large herbivores would all naturally have
created open ground where weeds like P. lanceolata
would survive before humans became implicated in its spread.
Such natural events would have occurred in the early to
mid-Holocene too and allowed its survival. Low frequencies
occur throughout these forest phases of the Holocene when
human agriculture was not a factor. P lanceolata
occurs often in the early regeneration phase after fire-disturbance
of woodland, however, which may have had a natural cause
or be due to the activities of Mesolithic hunter-gatherers
(Simmons 1996). Its most common palaeoecological presence,
however, is as a consistent indicator of forest clearance
for agriculture by Neolithic farming communities, associated
with pasture land and cultivation as it is today. Consistent
frequencies often begin around the Ulmus decline about
5,000BP, which may partly have been caused by the activities
of Neolithic farmers. In later prehistory and after, increasingly
intensive forest clearance provided widespread opportunities
for the spread of P. lanceolata, especially where
the land-use practised was for pasture and animal grazing.
P. lanceolata has effectively become recognised
as the signature of pastoral agriculture in pollen diagrams
(Behre 1981), with pollen frequencies often as high as
5-10% of total pollen, and occasionally much higher. It
can also form part of the arable herb suite, however,
and interpretation of its role in the agricultural weed
community needs careful consideration. Very high percentages
of P. lanceolata in more recent times may very
well reflect large areas of abandoned waste ground and
rough grassland as much as managed pasture.
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