| On Topic
The science behind
hedges to improve
image: Laurance Clark
the sheep loses just trying to deal with the
weather.
Reduced production costs?
So far the team has worked out that over the
three months of winter, if it averaged a chilly 6
°C outside, this would increase the energy
deficit by nearly 0.25 mega joules per sheep,
per day.
This means that 100 sheep would need an
extra 189kg of dry matter silage, just to produce
the energy they need to keep warm, energy
that is therefore not available for growth.
Advice from the experts
Senior Farming Advisor Helen Chesshire
said: “Studies have shown that in cold, wet and
windy weather, lamb losses can be reduced by
up to 30 per cent if good shelter is provided.
“Sheltered, well-drained fields provide the
best physical conditions for lambing and good
mothering. By creating the right conditions for
ewes and young lambs, lamb mortality can
actually be reduced compared to housed
lambing.”
Tree shelter is invaluable in cold, wet and
windy conditions, reducing the risk of
hypothermia in new born lambs and the risk of
mastitis in their mothers.
Cold, exposed and windy conditions can
lead to an increased risk o f ewes developing
acute mastitis. This reduces the ability of the
ewe to support her lambs, increasing the
likelihood of lamb mortality or poor growth
rates.
www.farmingmonthly.co.uk
Shelterbelts can also be designed to assist
natural behaviours of ewes and provide
opportunities for isolation during lambing.
Isolation increases the chances of early
development of a strong bond between the
ewe and her lambs, better suckling and
colostrum intake, reduced disease risk and
greater resistance to the cold. And of course,
trees are great for providing summer shade,
allowing the sheep to seek respite from the
sun.
Trees can also improve soil quality, reducing
waterlogged ground conditions associated with
causing lameness and liver fluke.
Cumbrian farmers Paul and Nic Renison
have been using a rotational grazing system
(aka “Mob Grazing”) for the past three years.
New trees and hedges planted to support
their mob grazing project are already
increasing shelter for their flock and
reducing lamb loss.
The farm is home to between 900 and
1000 ewes and in order to help make the
farm profitable for themselves and their
family, Paul and Nic have very clear
objectives about their farm management.
Some 700m hedges are already in the
ground, or planned, providing this exposed
farm with much more shelter. Hedges here
lead to better adjacent grass growth over a
longer season, and lower lamb loss rates.
The rotational grazing utilises this grass
growth well and improves sward diversity
with lower input costs. Increasing
earthworms counts are a success measure
for the farm as they improve soils by
aeration and pulling in organic matter which
is key in securing future soil productivity.
The Woodland Trust is working with a
number of UK farmers to increase the number
of trees and hedgerows on their land to protect
their flock. The Trust’s Woodland Creation team
have supported the planting of over 41km of
new and restored hedgerows last winter alone.
Together with the Soil Association and Royal
Forestry Society, the Woodland Trust is staging
an agroforestry conference at Cranfield
University on June 22 where farmers can
discover the many benefits of planting trees on
farms. The conference will showcase some of
the UK’s leading agroforestry systems and look
at the main steps and questions faced in
getting them off the ground.
National and international speakers are
included in the line-up, along with those
currently practicing agroforestry techniques,
and Charlotte Smith of BBC Radio 4’s Farming
Today will chair the sessions. For more
information and to book tickets search
“Agroforestry 2017”.
Find out more about how the Woodland Trust
can help you plant trees, visit
woodlandtrust.org.uk/plant
May 2017 | Farming Monthly | 11