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Jake · 30-01-2011, 09:19 PM posted to uk.rec.gardening

On Sun, 30 Jan 2011 17:49:41 +0000 (GMT), wrote:

In article ,
Jake wrote:

Perhaps the issue is that the spanish bluebell is aggressive and could
probably satisfy the definition of invasive before too long. Foreign
introductions usually turn out to be a mistake, not just in the UK of
course - Australia's battling cane toads and even camels! Here the
grey squirrel's killing off the red, well at least the virus it
carries is.

Er, no. It isn't significantly more invasive than the native one.
It is a bit, but not enough to get excited about.

Let's not forget that gardeners introduced Japanese Knotweed,
Hilalayan Balsam, the so-called "Oxford Ragwort" and others. OK, maybe
the last was introduced by botanists not gardeners.

Only the first is a serious problem. Himalayan balsam is very
invasive, but does not form monocultures by excluding all other
plants. And Oxford ragwort isn't a problem at all.

The point is that almost all of our ecology is new - 11,000 years.
We probably have the ecology that is most resistant to alien
species of anywhere on earth.

I'm worried about the "being" that's being released to combat
knotweed. If the experiment succeeds knotweed will presumably cease to
be a problem but then a horde of "beings" will look for an alternative
food source. It's called evolution I think.

They have been and are testing for that. Species-specific parasites
very rarely behave as you say.

Regards,
Nick Maclaren.

Nick

I have two areas of the garden planted with native bluebells and
they've stayed put. My next-door neighbour and I worked out that a
planting of spaniards by the next door but one neighbour took six
years to migrate as far as my garden. Hopefully they've all been
removed now!

The other next-door neighbour is a farm with a decent stand of
knotweed currently about 80 yards away from me! Himalayan balsam
appeared in the garden the year before last as a single plant but last
year I was yanking it up repeatedly. HB was thick in the field next
door last year. Granted that an upside is that HB's shallow roots
don't half dig up the top of the soil and make it all nice and
crumbly. But I digress. HB's controllable and responds immediately to
glyphosate. Yank it up before seeding and you contain the problem (if
next door also yanks it up!).

Knotweed's a bit more difficult and I would love to have a solution to
the impending problem - at the current rate of advance I guess I've
got about 4 years before it reaches me. But there's a big but!

Cane toads were Australia's answer to cane beetle. Supposedly species
specific.

You say that they have been AND ARE testing ..... AFAIK, the Welsh
Assembly Government approved the release of the parasite into the wild
in March last year. If they are still testing then that, to the
uneducated like me, implies that they do not know for sure. But they
have apparently released it.

So I'm worried. This doesn't seem to be a nematode!

Cheers
Jake