"anne" wrote in message
...
If I trim 4 foot from the height of a hedge will this give me 4 foot more
light on my allotment?

The problem is, that during the day the sun travels the length of a hedge
that runs all the way up the side of the allotment and the hedge puts 50%
of
the allotments's entire length in the shade. This is now - september. How
much will it decrease in winter and how much will it increase in summer?

My main question though, is does the amount you cut off equal the amount
of
sunlight you gain.

Hope you can help, I think I've made a mistake with my choice of allotment
:-(

If I have this straight your hedge runs East -West. If this is the case I
would expect that during the Winter when the sun is lower then every foot
you take off the hedge will release much more than a foot from being shaded.
When the sun is higher in the summer the effect will not be so great & may
even be less than a 1:1 ratio.

You could work it out for yourself. Measure the height of the hedge and then
measure how far out the shaded area is from the side of the hedge (not the
middle). If the hedge is 8 foot high and creates 16 foot of shade then you
know that each foot you take off the hedge will release 2 foot of ground
from the shade.

So measure the two distances and divide the width of the shaded area by the
height of the hedge to see how much you will release from the shade for
every foot you take off the hedge. This will be a "more or less" calculation
!!

I.