Monday, 14 January 2013

Mistletoe Miscellany

Apologies for the belated posting of this write up of our December meeting.

Jonathan Briggs, who has studied mistletoe for 30 years, gave a most interesting and amusing talk on this peculiar shrub. There are about 1500 mistletoe species worldwide but his talk concentrated on “our” mistletoe, Viscum album.  It is unusual in that it is a hemi-parasitic, evergreen shrub that grows on deciduous trees; mostly on apple but also on lime, hawthorn and poplar. It is the only native white-berried species in northern Europe. Because it does not grow on the ground, it forms a spherical growth and each branch bifurcates every year to give an exponential growth. It's such a unique shrub and has attracted myth and legend through history. It has pagan associations and is rarely seen in churches although it is common in churchyards.

In the UK, mistletoe is found predominantly in Worcestershire, Gloucestershire, Herefordshire and Somerset. It grows in much of Europe but is not found in northern countries. England is on its northern edge and it is rare in Scotland. Despite growing in orchard counties, its connection with orchards is in question and its success in these counties may be due to climatic conditions. Mistletoe’s preferred growth areas may be moving to the north and east, perhaps caused by climate change.

Mistletoe (c) Jonathan Briggs

There are only a few birds that will eat the berries: mistlethrush and blackcap are the most common. Blackcaps are the most efficient propagators of the seeds as they don’t eat them but wipe them from their beak onto a branch, from where the seed has a good chance of germinating. Trees are killed if too much mistletoe is allowed to grow on them because the nutrients are diverted away from the host. Its management is important so it is marketed around Christmas time, when there is a strong demand for it and the berries are approaching their best. However, the male non-fruiting shrub should also be removed.

We hope to see you at our next meeting on 7th February when Peter Garner will be talking about Notable Trees of the Malverns.

Derek, Malvern Local Group

1 comment:

  1. The Thrushes in knew about but I didn't know it was Blackcaps too. Thanks for the info.