Date: Tue, 28 Nov 2000 22:35:43 -0400 From: Botanique <botaniqu@pitcherplant.com> To: cp@opus.hpl.hp.com Message-Id: <aabcdefg3433$foo@default> Subject: Re: Tannins
Dear John,
>
> > I read an article by Rob Sacilotto (Botanique Nursery) in the June '98
> issue
> > and he says "Some [Sarracenia] may require tannins to produce pigment,
> > others may not." Is it known which ones require tannins? I would guess
> > that the more colorful varieties would benefit more from tannins, like
the
> > red and black-tube varieties of flava and alata maybe?
>
I was forwarded this query, and since my name and article were mentioned,
felt compelled to respond, though I am not currently on the list server.
First, the article on tannins,"The Use of Tannic Teas in Carnivorous Plant
Culture" appeared in Dec. 1996 volume 25, number 4 issue of the Carnivorous
Plant Newsletter. This was a summary of some experiments involving tannins
in Sarracenia pigment, morphology and also effects in other CP. It is easy
for any person to pontificate about the subject and make statements that
are not founded in reason and scientific method. To really know what is
happening, you first have to admit you don't know and want to find out the
truth. To anyone that "thinks they know"...show me the data. I used a
series of identical, cloned plants and controlled conditions to arrive at
conclusions. I am a Botanist with extensive training in plant anatomy,
morphology and physiology, so the tannin test had the usual experimental
details such as standardized tannin solution, control groups(not treated),
alternate chemical treatment (chelated iron), identical environment for all
groups, etc. The published article did not go into the massive data
collection and technique in detail because it would have engulfed a couple
issues with boring numbers. The results were evaluated and many people were
witnesses to the actual differences in plant shape, vigour and color. The
test plants were on display at a regional CP meeting here.
What is important to the grower is that tannins and the associated organic
acids:fulvic and humic acids, are groups of dynamic chemicals that effect
the soil chemistry in complex ways. These chemicals leach out of potted
plants, fairly quickly, depending on temperature and irrigation practices.
If you disturb the root system of some Sarracenia, the pigment fades from
root distress. So let's see, if I keep the plant in the same soil-it fades
from lack of certain chemicals that act as metabolic facilitators, and if I
repot the plant-it fades from root disturbance! That's where the peat tea
comes in, it:
#1.can bring the pH of soil down in soils neutralized by leaching,(this
completely changes (from neutral or near-neutral) the variety of
nutrients(Nitrogen, Iron. Calcium, Magnesium and many others) available to
the plant.#2 Replaces many organic catalysts and inorganic nutrients that
become scarce. #3. Allows chelation of Iron which is very important in
pigment formation. This is most likely accomplished by the breakdown of
tannic acids into fulvic and humic acids that bind with Iron and make it
available to the plant. Plants usually need a "chelated" form of Iron, rust
won't work!
Sarracenia treated with foliar and soil applications of commercial
chelated iron (non-tannic chelation) also showed improved color over
controls, but showed signs of chemical stress, commonly associated with
high conductivity soils (i.e.salt damage.) The beauty of the tannic tea is
that it does not behave like a salt, it has low conductivity (dissociation)
and is safer, longer lasting than chemical treatments.
The red pigment in several Sarracenia was unquestionably improved by the
use of tannic teas in established plants. Some plants that were planted in
a man-made bog had been there for over ten years and did not show "normal"
pigmentation during that time. Yet the same group turned red when tannic
teas were applied within five months. Most of the test plants were isolated
in pots. Results were clear: some pigmented groups of Sarracenia colored-up
and were more vigorous with tannic teas. All plants survived, treated or
not.
Some Sarracenia do not seem to change much with or without the tannins,
especially the lighter pigmented forms. S. flava var. rubricorpora showed
some improvment,slight improvement or dramatic improvement, depending on
the clone. The plants most affected/improved by the tannic tea included:
S.alata-black-red form, S.flava-SW Florida dark red form, S.flava-all
veined forms, S.purpurea-black-red, S.leucophylla-hot pink color forms.
S.flava var. cuprea (copper top) showed slightly better color but 25%
taller pitchers in the clones tested. S.minor also showed improvement.
No matter how you mix your soil, it will become eventually become lacking
in nutrients if you don't add them. You can overcome this several ways and
the above experiments were designed to help growers respond to a dilemma. I
seriously doubt anyone else can speak about this subject with the same kind
of factual backing; it's a royal pain to keep track of a large test group
(over 100 Sarracenia plants.) When I have some potted Sarracenia that need
a color boost, I give them a few applications of tannic tea while the
pitchers are forming. If it didn't work, I wouldn't waste my time doing it.
I would also add that if you grow high drainage, low pH plants, such as
N.villosa, N.lowii, N. macrovulgaris, N. burbidgea, you can really benefit
from tannic teas because the soil usually has a low organic content
(i.e.high mineral, such as perlite), and a tendency to go nuetral fast.
Nature creates these and rain/water distributes them.
This was not a "one paragraph" subject, and my apologies if this was a bit
tedious to read. Easy answers, on this subject, are trademarks of an
untrained mind. This subject is not simple, but I hope the important points
can be extracted by the reader, used to better their growing skills, and
perhaps encourage others to set up legitimate experiments, rather than
illegitimate comments, opinions, etc. I am still working on this subject
and hope to publish some updates once I get more info nailed down.
Meanwhile, see the above mentioned article for recipe information and other
helpful hints.
Sincerely, Rob Sacilotto/ Botanique (http://www.pitcherplant.com)
This archive was generated by hypermail 2b30 : Tue Jan 02 2001 - 17:35:15 PST