colchicum leaves for dinner
Jane McGary (Wed, 08 Jun 2005 18:48:03 PDT)

My contribution to the discussion on what slugs (and other pests) eat and
what they don't, and what they don't die of:

In my experience over 20 years with my present garden (which is in absolute
Slug Hell, also known as western Oregon), I have watched certain plants be
ignored by slugs for 6 or 7 years (e.g., Meconopsis grandis) and then
suddenly devoured wholesale, while other plants (e.g., Hosta) have been
eaten for several years and then the slugs started leaving them alone.

I have two theories about this. One is that slugs "learn" somehow (through
some inherited cellular chemistry? their reproduction pattern is very
peculiar) to eat new plants, such as the Meconopsis, once a certain number
of the population have tried the plant and not died of it. Another, which
I've read about, is that certain plants produce new toxins, or enhanced
levels of toxins, in response to predator pressure; perhaps hostas do this.

I've grown Cardiocrinum for most of that time. Slugs destroy young
seedlings (I lost a whole flat of them this year), but once the plants
attain near flowering size, they are only slightly damaged. All the plants
I have in the ground now are offsets, not seedlings, so perhaps they, like
the hostas (same family), produce some defense against the slugs eventually.

As for deer, they don't eat colchicums, hostas, or cardiocrinums. Also,
they seem to have an aversion to LILIES WITH RED STEMS, a characteristic
that I'll look for the next time I order lilies.

Jane McGary
Northwestern Oregon