Skip to Content.
Sympa Menu

nafex - [NAFEX] Cold Weather Pruning/Sugar Maples

nafex@lists.ibiblio.org

Subject: North American Fruit Explorers mailing list at ibiblio

List archive

Chronological Thread  
  • From: "David Consolvo" <fruitopia@nexet.net>
  • To: North American Fruit Explorers <nafex@lists.ibiblio.org>
  • Subject: [NAFEX] Cold Weather Pruning/Sugar Maples
  • Date: Sat, 15 Feb 2003 17:39:02 -0500

Thanks so much for this fascinating theory! I admit I had pooh-poohed the
idea that pruning can't be done mid-winter.

Perhaps this dehydration/rehydration is why sugar maples produce so much sap
at taps when nights are below freezing and days are above? The trees are
taking water from above to the roots for the night, and rehydrating from the
roots to above during the day?

Speaking of which, I have gotten SO much more maple sap this year than any
other. Some years I get almost none. I've wondered if it is because
winters here are too mild; good maple sugaring seems to be all in colder
areas. This has been our coldest winter in a long time, so I wonder if that
is improving maple sap production.


David Consolvo
Hungrytown, Virginia, 1,200 feet elevation
Zone 7


----------
>From: Bernie Nikolai <bnikolai@shaw.ca>
>To: North American Fruit Explorers <nafex@lists.ibiblio.org>
>Subject: Re: [NAFEX] Re: Cold weather pruning Advice
>Date: Sat, Feb 15, 2003, 5:10 PM
>

>Del wrote:
>
> What is the mechanism that allows a whole stick
>>of dormant wood to dry out through a small end cut? I thought the juices
>>quit running in the winter.......Del
>
>Hi Del,
> I'm no scientist, but I have thought long and hard about apple tree
>hardiness (of necessity) in my climate. The dormant scionwood stick won't
>dry out, as I assume you have it in the fridge in a plastic bag with damp
>paper in the bag. But I think you mean "why would the tree you took the
>scion from dry out and be injured?"
> Here's my theory, but keep in mind I have never seen any scientific
>studies to support my beliefs. In cold climates like ours, a fruit tree
>survives by ridding itself of as much moisture as it can in the cells. Ice
>crystals, which are very jagged, will rupture the cell walls, killing the
>tree if they don't. Apple tree hardiness really means the trees that can
>desiccate or dry themselves out the most, then rehydrate when it warms up,
>are considered the most hardy. Tender trees either don't desiccate enough,
>and the ice crystals in the cells rutures the cell, and kills the tree, or
>else they do desiccate enough, but can't rehydrate succussfully, so they die.
> Take a good look at your trees on any cold day, well below 0F. You
>will see the thumb thick brances are all shrivelled up, with wrinkled bark,
>similar to taking a long bath and seeing your skin on your hands all
>shrivelled up. When the temperatures get back to near freezing, whether
>that is in a day or in a month, take another look at the same branches.
>They are fully rehydrated and look totally normal again! I am not
>hallucinating on this one Del, check it out for yourself, its an amazing
>phenomenon! That's why the LENGTH of the cold spell is often more important
>than the actual minimum temperatures in our cold zones. A week of -40 (F or
>C) is way tougher on the trees than one night of -40.
> Now as to how the tree "rehydrates", there are only three possible
>ways, 1/through the roots even though the ground is frozen solid, 2/ by
>sucking in moisture from the outside air, or 3/ by a combination of both.
>It is possible only a very small amount of moisture from the roots is
>needed, at least compared to summer conditions with lots of leaves and
>evaporation. So possibly the roots do send a very small amount of moisture
>back up to the branches despite being frozen. Or possibly the tree can just
>suck the moisture straight out of the air. After all, that's why we store
>dormant scions in a humid environment by adding damp paper. If the scions
>are stored at the right temperature, but bone dry, they often die in storage
>after a while. So obviously they have the ability to some degree to pick up
>moisture from the atmosphere. And also it doesn't have to be a lot of
>moisture, but it appears to be a very delicate balance, and some small
>amount of moisture is essential.
> Pruning in cold weather upsets this delicate balance somehow, and I
>believe its because the tree looses moisture that it can't replace in
>winter. I've noticed the same phenomenon one year with "scoot", a waxy
>coating with thiram to deter mice and voles. I really coated a few small
>trees, way thicker than normal, so they had a "coat of wax" on them. I had
>SEVERE winter damage on those trees, even though they were very hardy! I
>believe this was due to the tree being disrupted in terms of getting out or
>getting in moisture during the winter months. The wax didn't allow normal
>transpiration.
> So Del, most of the good folks on this list live in the virtual
>"tropics" compared to our winters, and can get away with all kinds of things
>such as mid winter pruning that we can't begin to get away with. But it
>makes growing an orchard in our climates all the more challenging and fun!
>We all have different challenges no matter where we grow. My advantage is
>all my trees are fully organic and never sprayed. There is no such thing as
>a codling moth, apple maggot, borer, plum circulio, or apple scab at my
>orchard, and the fruit is perfect or very near perfect without any sprays.
>I suspect very few on this list can grow high quality pome fruit in the same
>way without any pest control of any kind.
>Bernie Nikolai
>Edmonton, Alberta
>
>
>_______________________________________________
>nafex mailing list
>nafex@lists.ibiblio.org
>Most questions can be answered here:
>http://lists.ibiblio.org/mailman/listinfo/nafex
>File attachments are accepted by this list; please do not send binary
>files, plain text ONLY!
>Message archives are here:
>https://lists.ibiblio.org/sympa/arc/nafex
>To view your user options go to:
>http://lists.ibiblio.org/mailman/options/nafex/XXXX@XXXX (where XXXX@XXXX is
>YOUR email address)
>NAFEX web site: http://www.nafex.org/
>
>From pinewoodel@hotmail.com Sat Feb 15 23:24:59 2003
Return-Path: <pinewoodel@hotmail.com>
Delivered-To: nafex@lists.ibiblio.org
Received: from hotmail.com (f166.pav1.hotmail.com [64.4.31.166])
by happyhouse.metalab.unc.edu (Postfix) with ESMTP id 1332D20025
for <nafex@lists.ibiblio.org>; Sat, 15 Feb 2003 23:24:59 -0500 (EST)
Received: from mail pickup service by hotmail.com with Microsoft SMTPSVC;
Sat, 15 Feb 2003 20:26:08 -0800
Received: from 209.191.195.39 by pv1fd.pav1.hotmail.msn.com with HTTP;
Sun, 16 Feb 2003 04:26:08 GMT
X-Originating-IP: [209.191.195.39]
From: "del stubbs" <pinewoodel@hotmail.com>
To: nafex@lists.ibiblio.org
Subject: Re: [NAFEX] Re: Cold weather pruning Advice
Date: Sun, 16 Feb 2003 04:26:08 +0000
Mime-Version: 1.0
Content-Type: text/plain; format=flowed
Message-ID: <F166XtHfGfZXDwXiBX50002e3ac@hotmail.com>
X-OriginalArrivalTime: 16 Feb 2003 04:26:08.0777 (UTC)
FILETIME=[874DBF90:01C2D573]
X-BeenThere: nafex@lists.ibiblio.org
X-Mailman-Version: 2.1.1
Precedence: list
Reply-To: North American Fruit Explorers <nafex@lists.ibiblio.org>
List-Id: North American Fruit Explorers <nafex.lists.ibiblio.org>
List-Unsubscribe: <http://lists.ibiblio.org/mailman/listinfo/nafex>,
<mailto:nafex-request@lists.ibiblio.org?subject=unsubscribe>
List-Archive: <https://lists.ibiblio.org/sympa/arc/nafex>
List-Post: <mailto:nafex@lists.ibiblio.org>
List-Help: <mailto:sympa@lists.ibiblio.org?subject=HELP>
List-Subscribe: <http://lists.ibiblio.org/mailman/listinfo/nafex>,
<mailto:nafex-request@lists.ibiblio.org?subject=subscribe>
X-List-Received-Date: Sun, 16 Feb 2003 04:24:59 -0000


What a response Bernie! I am embarrased to say I had not noticed the
shrinkng / swelling of trees in winter......that is what assumption
does......though my wife who has lived here all her life says she has
noticed it. We have a warming trend coming, supposed to get up to 25F above
soon.....so you can bet I'll be out observing and learning. thanks, Del
Del Stubbs zone2/3


_________________________________________________________________
MSN 8 with e-mail virus protection service: 2 months FREE*
http://join.msn.com/?page=features/virus



  • [NAFEX] Cold Weather Pruning/Sugar Maples, David Consolvo, 02/15/2003

Archive powered by MHonArc 2.6.24.

Top of Page