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nafex - [nafex] Re: Hand Pollenate Pawpaws.

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  • From: "Christopher Mauchline" <mauch1@aol.com>
  • To: nafex@egroups.com
  • Subject: [nafex] Re: Hand Pollenate Pawpaws.
  • Date: Wed, 24 Jan 2001 14:44:50 -0000

If you have more than one tree, you can skip the capsule part. Just
find a ripe (male) blossom on one tree - pick it. Take blossom and
brush over to tree to be pollinated. Find female stage blossom, use
brush to gather pollen from male blossom and brush on the female
blossom. You do sacrifice the blossom you pick, but if it's early in
the flowering season, it may not be pollinated anyway.

Chris Mauchline
SE PA, zone 6
P.S. I also learned the mistake of buying "seedling" Pawpaws. I think
even though little work has been done, that at least some of the
selected varieties are far superior.


--- In nafex@egroups.com, "Gordon C. Nofs" <gcnofs@h...> wrote:
> Ginda
> If you read the information, you will find as I did that the
pollen will
> not ripen in a plain bottle. Hence the gelitin capsules which it
does ripen.
> I collect one day and put on the next and collet more. I continue
this
> process untill I get tired of it or run out of ripening blossems.
Which
> takes weeks.
> Did you know the the cousin the Cherimoya grown in orchards of
California
> are all hand pollenated?
> Gordon
>
> *******************************************************************
> What a great post. Have you ever tried Q-tips instead of the
capsule
> and brush?
>
> "Gordon C. Nofs" wrote:
> >
> > Thought that there might be some interest for some out there.
> >
> > 1
> >
> > Doing what comes unnaturally
> > How to hand-pollinate pawpaws
> > By Neal Peterson
> >
> > Some people find that Pawpaw trees just don't produce
fruit. "Why?" they
> > ask. The answer usually is, "They need a pollinator." Sometimes
this
> > means they need a helping hand in their pollination. Literally.
> > Hand-pollination. The question then be-comes, "How do you do it
if you've
> > never done it? When is the pollen ripe? When is a flower in the
female
> > stage and most receptive? How do you do the act itself -
transfer the
> > pollen to its appointed spot?" It's all very easy, but - like
human sex -
> > it ~ isn't necessarily obvious how to do It.'he first time. Here
are some
> > simple pointers to guide you if you aspire to pollinate pawpaws
by hand.
> > Pawpaw blossoms begin life as females and later become males.
They are
> > designed this way to discourage
> > self-pollination. In the female stage the petals are held rather
tightly
> > together, forcing the small flies and beetles that visit the
flowers,
> > searching for nectar, to brush past the stigmas where the pollen
they
> > carry on their backs can be deposited. In this stage, the petals
will
> > have turned color, from green to maroon (although some green may
still
> > show) but the anthers will be tightly pressed together as a
solid green
> > ball, and the stigmas will appear green and shiny.
> > In the later male stage, the petals darken more, the fetid
flower odor
> > intensifies, the ball of anthers loosens (no longer solid) and
the
> > anthers turn from green to brown, shedding the yellow dust-like
pollen.
> > In this stage, the petals flare back, allowing the visiting
insects to
> > brush easily past the anthers, thereby collecting pollen on
their backs.
> > The first trick for the hand pollinator is collecting the
pollen. There
> > are many ways to do this, but my own
> > Preference is to use large empty gelatin capsules (size XXX)
that you may
> > buy at health food stores. I open
> > the capsule and use one end as a cup to scrap the ripe-with-
pollen
> > anthers, causing them to fall into the capsule. I then close the
capsule
> > and label the contents with an indelible pen. These capsules,
being made
> > of gelatin, absorb moisture, promote the anthers to release
their pollen,
> > which then adheres to the sides of the capsule. I then use a
very small
> > camel's hair brush to collect the pollen from the sides of the
capsule,
> > and apply the pollen to the stigmas of the female flower. For
the sake of
> > thoroughness, and to learn the results of my efforts, I also tag
the
> > flowers I have pollinated. The final pointer has to do with
picking the
> > right time of day and the right type of day for pollinating. I
find that
> > I get the best results on a perfect spring day, when the sun is
bright,
> > the air is warm, the breezes gentle or not at all. I don't do it
in early
> > morning or late in the day. When in doubt about how to do it,
think like
> > a flower, think like a beetle.
> >
> >
**********************************************************************
***
> > *************
> > My Botanical Rendezvous
> >
> > By Colleen Anderson
> > I'm an infamously bad gardener, but six years ago I planted a
Pawpaw seed
> > in my yard, and it grew. I nursed the little sprout along and,
about the
> > second year, transplanted it to the sunny side of Arlington
Court, where
> > I live. It thrived. Last year, the first blossoms appeared -
only four of
> > them, but there was no denying it - my tree was at least a
teenager.
> > This year, it's an adult. The tree is tall and straight, and the
lovely,
> > blood-brown, bell-shaped flowers are everywhere - there must be
two
> > hundred. My tree could be fruitful - but, like people, paw-paws
need
> > intimate company in order to reproduce - and there isn't another
Pawpaw
> > within shouting distance.
> > So I have been assisting nature. My tree's mate came from a fine
stand of
> > pawpaws in Kentucky. I carried the precious pollen back in small
> > capsules. On a beautiful, warm day last week - the perfect sort
of day
> > for romance -1 had a go at hand pollinating. It didn't take
long, and it
> > wasn't very exciting - dipping a small brush into the pollen
capsules and
> > delivering it to the waiting blossoms - but still, I tried to
> >
> > 2
> >
> > accomplish it without attracting attention. Plants may not care
about who
> > watches their sexual encounters, but I couldn't get over the
feeling that
> > there was something illicit about this endeavor.
> > Nevertheless, word got around. By that evening, my neighbors
were teasing
> > me about my midaftemoon botanical rendezvous. All over the
block, they're
> > calling me "Madame Pawpaw."
> > I feel more like a grandmother-in-waiting. I'm looking forward
to the
> > story this summer will tell. Will my lovely young tree be
compatible
> > with her Kentucky gentleman? Will the blossoms swell into
clusters of
> > fruit? Will we have Arlington Court paw-paws this fall? Stay
tuned. With
> > luck, I'll be making a birth announcement.
> > This essay was originally broadcast as a commentary on West
Virginia
> > Public Radio in April 1996. The
> > harvest was bountiful.
> >
**********************************************************************
***
> > *********
> > Pawpaws in the Garden
> > SITE, SOILS, AND HABITAT. Although the Pawpaw is capable of
fruiting in
> > the shade, optimum yields are obtained in open exposure, with
some
> > protection from wind (on account of the large leaves).
Germinating
> > seedlings, however, will not survive under those conditions
because they
> > are extremely sensitive to full sunlight, which can kill them.
Shading
> > for the first year, and sometimes the second, is normally
required, and
> > it is for this reason that pawpaws are almost always found in
nature as
> > an understory tree. The soil should be slightly acid (pH 5.5-7),
deep,
> > fertile, and well-drained. Good drainage is essential to
success. Pawpaws
> > will not thrive in heavy soil or water-logged soil. In habit it
is a
> > small tree, seldom taller than 25 feet. Grown in full sun, the
Pawpaw
> > tree develops a narrowly pyramidal shape with dense, drooping
foliage
> > down to the ground level. In the shade it has a more open
branching habit
> > with few lower limbs and horizontally held leaves.
> > PROPAGATION BY GERMINATION. Pawpaw seed is slow to germinate but
not
> > difficult if certain procedures are followed. Do not allow the
seed to
> > dry for long periods (ie., months) because this can destroy the
immature,
> > dormant embryo. To break dormancy, the seed must receive a
period of
> > stratification (exposure to cold temperatures) for 90-120 days.
this may
> > be accomplished by sowing the seed late in the fall and letting
it
> > overwinter; the seed will germinate the following year in late
July to
> > late August. Another way is to stratify the seed in the
refrigerator
> > (32-40F/0-5C). In this case the seed should be stored in a
plastic
> > ziplock bag with a little moist sphagnum moss to keep the seed
moist and
> > suppress fungal/bacterial growth. After stratification the seed
should be
> > sown in a well-aerated soil mix, pH 5.5-7, with an optimum
temperature of
> > 75-85F (25-30C). The root will normally emerge from the seed
coat on the
> > 18th day, develop into a taproot about 10 inches deep, and then
send up a
> > shoot on day number 64. Germination is hypogeal: the shoot
emerges
> > without any cotyledons. For the first two years growth is slow
as the
> > root system establishes itself, but thereafter it accelerates.
> > Fruitbearing normally begins when the sapling reaches 6 feet,
which
> > usually requires six to eight years.
> > PROPAGATION BY VEGETATIVE MEANS. Pawpaw clones are easily
propagated by a
> > number of grafting and budding techniques, such as whip-and-
tongue,
> > cleft, bark inlay, and chip budding. The only method that does
not
> > produce good results is T-budding. Shoot cuttings have proved
virtually
> > impossible to root, while root cuttings are usually successful.
Although
> > it is common for a Pawpaw to sucker from the roots, and would
therefore
> > seem a natural way to propagate a clone through transplanting
root
> > suckers, in practice this is extremely difficult. Pawpaws are
ordinarily
> > quite difficult to transplant. They have fleshy, brittle roots
with very
> > few fine hairs. Experimentation has shown that, to be successful,
> > transplantation should be done in the spring at the time that
new growth
> > commences, or soon after. (This is basically the same as for
magnolia.)
> > If many roots are lost, it may be desirable to prune the top to
bring it
> > into balance with the remaining roots.
> > 3
> > POLLINATION, NATURAL AND ARTIFICIAL.
> > Pollination is the major limitation to Pawpaw fruit set. The
flowers are
> > protogynous, meaning that the stigma (the female receptive
organ) ripens
> > before the pollen, and is no longer receptive when the pollen is
shed.
> > Thus the flower is designed not to be self-pollinated. In
addition,
> > Pawpaw trees are self-incompatible, requiring pollen from a
genetically
> > different tree in order to be fertilized. Finally, the natural
> > pollinators of the Pawpaw-various species of flies and beetles-
are not
> > efficient or dependable. Although it requires a little extra
labor, hand
> > pollination can be well worth the effort and can be done as
follows:
> > Using a small, flexible artist's brush, transfer a quantity of
fresh
> > pollen from the anthers of the flower of one clone to the ripe
stigma of
> > the flower of another clone. Pollen is ripe when the little ball
of
> > anthers is brown in color, loose and friable; pollen grains
appear as
> > yellow dust on the brush hairs. The stigma is ripe when the tips
of the
> > pistils are green and glossy, and the anther ball is still hard
and
> > green. Do not overburden the tree with fruit, as this will
stress the
> > tree, resulting in smaller than normal fruit, and may cause
limbs to
> > break under excessive weight.
> > PESTS. In its native habitat the Pawpaw has few pests of any
importance.
> > The worst pest is Talponia plummeriana, the Pawpaw peduncle
borer, a
> > small moth larva (about 5 mm long) that burrows in the fleshy
tissues of
> > the flower, causing the flower to wither and drop. In some years
this
> > borer is capable of destroying the majority of blossoms.
Another pest is
> > Eurytides marcellus, whose larvae feed exclusively on young
Pawpaw
> > foliage, but never in great numbers. The adult butterfly is of
such great
> > beauty that this should be thought more a blessing than a curse.
> > Sometimes the fruit surface may be covered with patches that are
hard and
> > black; this is a fungus infection, but it seldom has any effect
on flavor
> > or edibility. Deer will not eat the leaves, twigs, or fruit.
Outside its
> > native region, the Pawpaw is sometimes reported to be plagued by
pests,
> > but this may be because of poor health resulting from improper
soils and
> > an unsuitable climate.
> > The Pawpaw Foundation, August 1990
> >
> > Bees show no interest in Pawpaw flowers. The task of pollination
is left
> > to unenthustic species of flies and beetles. A better solution
for the
> > home gardener is to hand pollinate. Using a small soft artist's
brush to
> > transfer pollen to the Stigma (Female part of the blossom)
Pollen is
> > ripe for gathering when the ball of anthers is brownish in color
loose
> > and friable. (Male part of blossom, up to top inside flower
above the
> > female part) Pollen grains should appear as small beige colored
> > particles on the brush hairs. The stigma (female part) is
receptive when
> > the tips of the pistils are green, glossy, and sticky, and the
anther
> > (male part) is firm and greenish to light yellow in color.
> > So the female part is ready when the male part is not in
the same
> > blossom.
> >
> > Gordon C. Nofs
> > Flint, Michigan
> > gcnofs@h...
> >
> > _________________________________________________________________
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>
> _________________________________________________________________
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