rot and borer resistant iris: a myth?

Jim Wilson said:
 >> The need for spraying, though, probably depends a lot more on where you
 >> live than on what varieties you choose.  In large sections of the
 >> iris growing world, it's possible to go for a while, years even,
 >> without spraying, and then suffer some serious losses, whatever you
 >> have chosen.

Sobering news.  There are not bearded cultivars that are strongly rot and borer
resistant? I'm willing to go back completely to pre-1950s varieties if need be.
If this search is fruitless for a large swath of the U.S., then be prepared for
AIS membership to drop significantly in the coming years.  Reluctance to use
garden chemicals in on the rise, more and more of them are being removed from
the market, and beautiful "new" perennials of all kinds that don't require them
are flooding into nursery commerce.

Re nematodes: As an organic gardener, I'd love to see research prove them
effective against the iris borer.  (Of course, this would still leave the rot
and leaf-spot problems unsolved.)  But aren't larva-eating nematodes soil
dwellers?  That is, wouldn't borers be safely out of the soil and in the iris
by the time they're at the stage where they'd be attractive to nematodes?

  >> the AIS standards are our best hope for maintaining perspective.  One
  >> could argue that the casual grower's interaction with catalogs that
  >> stress pretty flowers alone is where the perspective isn't present.
  >> Those who take the time to learn and appreciate the full set of
  >> criteria that the society urges are the ones who will end up
  >> recommending plants closer to your ideals.

Wish I could believe that, but so many of the AIS standards are moving targets
having to do with bloom form (size, wide and flaring falls, ruffling, closed
standards, etc.) which are of virtually no importance to me compared with
garden toughness.  Even substance, branching, and bud count are values I'm
willing to sacrifice to some extent for a plant that will perform reliably.

Re the casual growers: These would be people who get their bearded iris not
from iris specialists, but general garden catalogs?  The TB selections of some
of the largest U.S. perennial merchandisers,  Wayside and White Flower Farm,
consist largely of fairly recent Dykes and other AIS award winners. Are these
indeed the iris to be 'pushing' to the general gardeer, or are there other
cultivars with less perfection of appearance but stronger constitutions?

Perhaps my impression is wrong, but it has always seemed to me looking in at
the iris world from the outside, that there was a point in iris gardening
history when rot and borers were not such enormous problems.  Then they began
to be.  I can't pinpoint the period, but it seems to have been somewhere in the
late 40s and early 50s.

Reinforcing this idea for me was the difference in treatment of the topic of
pests and diseases in Sidney Mitchell's _Irises for Every Garden_ and a later
(early '60s?) book by Leslie Cave (British).  But what had the strongest impact
was probably R.W. Munson's introduction to _Hemerocallis: The Daylily_. It is
is an impassioned plea to daylily hybridizers not to let disease and insect
susceptibility creep further into the Hem. gene pool:

  "We have seen breeders in other genera march heedlessly into the future --
  a future dimmed because they were indifferent and ther plant became too
  difficult to grow or too much of a 'nuisance'."

Munson's close association with Steve Moldovan leaves little doubt of the
identity of one of these "other genera".  Is Munson all wet here?  Did not the
the quest for ruffling, size, new colors and patterns, etc. lead iris
hybridizers to overlook infirmities?  (In other words, will I not be able to
find older cultivars that predate this terrible turn because it didn't really
happen that way?)

 Nell Lancaster, Lexington, VA   75500.2521@compuserve.com    USDA zone 6b
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