

PUBLISHED IN FEBRUARY, MARCH, APRIL, AUGUST AND SEPTEMBER BY 
O. M. SCOTT & SONS CO. MARYSVILLE, OHIO 


Sixteenth Year 


_Number 77 


WINTER DAMAGE TO LAWNS 
N THESE nice fall days it is difficult 
to write about what may come in the 
dreary days of winter. Even so, after the 
severe damage to lawns during last winter 
it seems advisable to discuss what may 
happen in the next season of snow and ice. 
Much of the injury during cold weather 
is due to causes beyond control such as 
extreme cold with high winds at a time 
when grass is without the protection of a 
blanket of snow. Frequent freezing and 
thawing is especially damaging in heavy 
and poorly drained soils. In some winters 
a fungus may attack grass and cause a 
harmful disease called Snowmold. Turf 
damage from Snowmold was quite gen- 
erally reported last winter. 
Most attacks of Snowmold are thought 
te be caused by the fungus Fusarium 
nivali. This is dormant in soils most of the 
time but may become active when the 
Results of an attack of Snowmold on putting green turf. Note various sizes of affected spots 
condition is favorable for its development, 
namely, temperature just above freezing 
in combination with excess moisture. 
Quite often snow is associated with these 
conditions as when a soft snow falls on 
unfrozen ground or during melting of a 
heavy snow. In spite of the inference of 
the name, the disease Snowmold may 
appear even though no snow is present. 
In the early stages of the disease the 
fungus may appear as a thick cottony 
growth, covering definite but irregularly 
shaped patches. When wet the patches 
have a slimy feel. As the fungus grows it 
enters the grass blades and stems to break 
down the cell structure. As the grass dries 
it takes on a dirty, whitish-gray color. 
It is not so difficult to distinguish 
between the damage of Snowmold and 
other winter kill. In the latter case large, 
definite areas will be brown and dead 

compared to the lead pencil. Photos courtesy Green Section U.S. Golf Association. 
COPYRIGHT BY O. M. SCOTT & SONS CO. 
