[LCN Newscast] English Ivy, the OTHER Kudzu

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English Ivy, the OTHER Kudzu

Do you have ivy on one of your trees?  If so, ask yourself how
long you want to keep that tree alive.  Because in the in the
long run, you can't have your tree and ivy too...


"Hedera helix" is commonly called English ivy.  It is a native of
Europe, but has become naturalized in America after importation
by English colonists.  It is considered invasive.

English ivy outcompetes both grasses, herbs and trees, often
reducing animal feeding habitats.  In warm areas, H. helix can
grow throughout the year and can outcompetes native vegetation
that is dormant during the winter.  Ivy is a notorious refuge for
rats and other undesirable vermin.  Many gardeners and home
landscapers remove ivy and replace it with plant species likely
to attract desirable wildlife such as birds, butterflies, and
beneficial bugs.  For trees it poses the following problems:

- Ivy competes with the trees, especially seedlings, for water
and nutrients.
- Ivy vines eventually grow into a dense cover on the bark of the
tree's trunk. depriving the bark of the normal contact with air
and micro-organisms.
- Ivy vines grow to a very large size - often four or more inches
in 30 or less years - and have a very high water content thus add
considerable weight to the tree making it more susceptible to
toppling and blow-down.
- The stiff, waxy characteristics of Ivy leaves hold water, ice,
and snow which also add to weight and exacerbate conditions
leading to toppling and blow-down.
- Mature Ivy grows in spiral pattern as opposed to the
horizontal-vertical pattern of the immature plant thus it 'furls'
out around the branches and trunk further reducing the ability of
the tree to perform photo-synthesis.
- When Ivy grows up the tree seeking the light it needs to mature
and propagate, it eventually covers the apical stem or apex of
the tree.  The tree reacts as if it has been topped: experiencing 
biologic stress and sending messages of its distress out to the
types of micro-organisms whose purpose is to hasten the demise of
the tree.
- The Ivy growing around the tree has supplanted the deciduous
plants which have a growth and decay cycle that replenishes the
nutrients in the soil.


How to Remove Ivy from Trees:

(Here are the basics, details are at
http://www.noivyleague.com/Pages/rem_meth_girdling.html )

- Cut the vine at waist height, be careful not to cut into the
tree bark.
- Loosen the vine around the tree base.
- Generally is best NOT to remove the upper vines, as it can
damage the bark, and bring down branches or yellow jacket nests
onto your head.  The vines will eventually die and fall on their
own.
- Remove the roots.  If the root can not be removed by hand,
strip the bark and notch the exposed section of the vine.  Paint
on an undiluted herbicide such as glyphosate.
- If English ivy is growing on tree-ferns, take care that all
pieces of the ivy are removed.  The growth of H. helix can be
sustained by the fibrous nature of the trunk.


Sources:
http://tncweeds.ucdavis.edu/moredocs/hedhel01.html
http://www.noivyleague.com/

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