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Diseases and Their Control 
Ray Blight or Flower Spot 
SYMPTOMS. The petals first show little spots and 
then the entire petal begins to rot. May be caused 
by Botrytis or Ascochyta. Botrytis is spread _pri- 
marily by splashed water. 
CONTROL. It is controlled by lowering humidity or 
spraying plants with Parzate when they show color. 
Spray with Parzate one ounce to 4 gallons of water 
plus one-third teaspoonful of Du Pont Spreader 
Sticker on the flower from below and above as soon 
as color shows and continue at 5-day intervals. 
Orthocide 50W one ounce to 4 gallons of water plus 
spreader used as a spray similar to Parzate was 
found a good control. An electric fan, placed above 
the plants will circulate the air sufficiently to re- 
duce disease. 
Root Knot Nematode 
SYMPTOMS. The nematodes or eelworms bore into 
the roots of the plants and cause knots or galls to 
develop on the root systems. As a result the plants 
are weak, yellowish and stunted in growth. 
CONTROL. Steam sterilization of the soil is very 
effective in eliminating the nematodes. Dowfume G 
is a good soil fumigation that will kill nematodes 
and not do any damage to the surrounding plants. 
Rust 
SYMPTOMS. Chocolate brown powdery pustules on 
lower surface of the leaves. 
Dodder Growing on Mums 
CONTROL. Parzate, one ounce to 4 gallons of water 
is most effective. 
Septoria Leaf Spot or Leaf Blight 
SYMPTOMS. Distinct circular spot on the leaves. 
These are greyish-brown in color and become brittle 
in the center. Affected leaves may turn yellow and 
die. More prevalent in the open. Some varieties are 
more susceptible than others. Sea Gull is very 
susceptible. 
CONTROL. When cuttings are received, dunk the 
tops into Fermate (2 tablespoonfuls to a gallon). 
Spray the plants with Parzate one ounce to 4 gallons 
of water plus one-third teaspoonful of Du Pont 
Spreader Sticker every 10 to 14 days. Cloth house 
mums should be kept covered until the buds can 
be seen. 
Verticillium Wilt or Seidewitz Disease 
SYMPTOMS. Margins of leaves turn yellow and even- 
tually wilt or dry up. This begins at base of plant 
and works up the stem. May affect one side of a 
stem or plant more than the other. No distinct spots. 
Varieties vary in resistance to this disease. 
CONTROL. Verticillium wilt can be avoided by pur- 
chasing our disease-free cuttings produced from 
cultured stock. It is also necessary to plant only into 
sterilized soil. 
Septoria Leaf Spot 
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