X-Message-Number: 23393
From: "Basie" <>
Subject: What one can learn from frozen Turf again  (2)
Date: Fri, 6 Feb 2004 18:25:36 -0500

      Page 2
When slow freezing occurs, water is slowlydrawn out of the cells and all
freezable wateris crystallized in the intercellular spaces. Ifsuch a
condition is not prolonged, the plant mayescape injury.Turf Killed at Time
of ThawWhen freezing occurs, water is pulled fromthe cells and the cell wall
is pulled inward. Theprotoplasm in the cell becomes plasmolized, orballed
up. Unless the protoplasm is well sup-plied with bound or unfreezable water,
it be-comes brittle. Upon thawing, water rushes backinto the cell through
the highly permeable cellwall, and the protoplasm may be stretched
andsubjected to shear forces sufficient to destroyit. Under these
conditions, turf is killed at timeof thaw.Turf Killed While FrozenThe work
done by Dr. Jack Le Bean, of bridge Experiment Station in Alberta,
Canada,indicates that fungi in plants produce gaseswhile the plant is
frozen. These gases may causedeath. This production of toxic gas and
trafficon frozen turf are the two main causes of turfdeath while still in a
frozen state.The most comprehensive work on ice sheetdamage has been done by
Dr. James Beard ofMichigan State University. Some of the mech-anisms of ice
sheet damage suggested by Dr.Beard are the depletion of oxygen, the
accumu-lation of carbon dioxide and the leaching ofcellular constituents.
Although Dr. Beard hasthus far reached no definite conclusions on thematter,
his work indicates that direct effects oflow temperature may be more
important thanany of the mechanisms of ice sheet damage.Turf Killed After
ThawingMany of the common pathogens associatedwith winter injury are
apparently very active,and their destruction may be most pronouncedjust
after thawing begins and when the plantis striving to re-initiate
growth.What Do When Occurs1. Water lightly and regularly until the plantcan
re-establish its root system.2. Where no plant is left, replant
followingwhatever renovation is possible with spiker andperhaps some
vertical mowing or vertical slicing.3. Gentle treatment of the turf as if
the en-tire damaged portion were all new seedlings,which in effect it is, is
called for.When frozen soil begins to thaw, heaving mayWinter injury has
been so widespread andalso occur. Heaving may cause a large portionsevere
recently that numerous experiment sta-of the root system to be pulled off.
If crowntions have begun to study the matter moretissue has also been
damaged, little of the plantcritically. There has been a renewed interest
inis left to support continued growth, and deathsoil warming by the use of
electric heatingoccurs when the immediate energy supply iscables and in the
use of various types of cover-exhausted.ings.Desiccation is the drying out
of soil and planttissues. It may cause severe damage in winterif adequate
moisture is not maintained. In theabsence of snow cover, moisture may be
lostfrom frozen soil by sublimation. This means thatthe moisture may pass
directly from solid togas without becoming a liquid which is of coursethe
only form available to the plant. When thishappens, plants simply die from
drought.Ice Win t Learn The Cause, Improve The Cureby JAMES W. TIMMERMAN,
Agronomist, USGA Green Sectionthe last five years, golf courses in
theNorthern United States have experienced winterinjury as severe as any in
history.What are the causes of winterkill and what isknown of their
destructive action?The ravages of winter are easily classed intosix
categories:ASSOCIATED ICE SHEET DAMAGEThe extensive damage suffered from
ices h e e t s d u r i n g t h e 1 9 6 1 - 6 2 w i n t e r s e a s o
nprompted considerable research. Investigatedcauses of ice sheet damage
include:1. Oxygen suffocation under the ice sheet.MARCH 19703TER at They
Look What to do About Themby M. GRIFFIN, Agronomist, USGA Green Sectionturf
problems can be deadly, unpre-in the sap solution and in intercellular
spacesdictable, and the worst problems those whoas well as within the cell
proper. When rapidwork with turf can encounter. The problemsfreezing occurs,
ice crystals form within thethough, are not insoluable. We can examine
howcell, and the protoplasm (the vital part of theturf is damaged during the
winter and, wherecell) may become disorganized. Intercellular icepossible,
explain what can be done to lessenof this kind will almost always cause
severethe problem.damage or death.Turf Killed at Time of FreezingIf the
plant has not had time to "harden"properly it may die at the initial freeze.
In thiscase, the plant is rapidly growing and may bein a rather succulent
condition with a high con-tent of water in its cellular structure. Water
isWhen the plant is "hardened" by the gradualonset of cold weather and a
slowing down of thegrowth process, the tissues lose much of theirfree water
and the sap solution becomes moreconcentrated. Biochemical and
biophysicalchanges cause the protoplasm to become hy-drated with water in a
"bound" or unfreezableform and death is less likely to occur.Learnthe
laNorthern Uniterinjury as severeWhat are theknown of their The ravagessix

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