CHICAGO American Rill Company NEW YORK 
TEPP sprays are all quite effective. In aerosol form 
Parathion and Dithio can be used. The systemics are 
also valuable but are somewhat slow acting. 
SLUGS, SNAILS 
Chlordane in which metaldehyde is used as an at- 
tractant is effective. 
SOWBUGS 
Sometimes called pillbugs, these pests chew stems on 
young plants. DDT is effective. 
SYMPHYLIDS 
The root system of plants is chewed by these pests 
and growth is severely checked. They are white to light 
tan, about 4% inch long, with two prominent antennae 
or feleers on their head. They move quite rapidly when 
disturbed and will dart back into soil crevasses if ex- 
posed to the light. A Lindane soil drench using 1 oz. of 
wettable powder to 30 gal. water which is applied to 
100 sq. ft. of bench area is effective. In raised benches, 
steaming will control them, but since they move down- 
ward it is not an effective control in ground beds. The 
Lindane treatment will last about one year. 
SPITTLE BUGS 
A frothy mass resembling spit is the hiding place of 
this small greenish colored insect. Lindane dusts or 
sprays will control it. 
TARNISHED PLANT BUGS 
These pests sting the growing tips which wilts and 
often abnormal branching is noted. Affected shoots 
seldom flower. DDT or Parathion in dust or spray form 
will control this pest but must be applied regularly. 
TERMITES 
Roots or stems may be “hollowed out” from attacks 
of this pest. No control is possible in this stage other 
than destruction of the plants. Termite swarms can be 
killed by Lindane or Chlordane dusts or sprays. 
THRIPS 
There are several types which attack the leaves and 
flowers at various times of the year. A short silvery 
colored streak is indicative that thrips are attacking 
the leaves and on petals the color may be brown. 
Lindane, Malathion, DDT, Parathion, Aldrin, and 
Dieldrin are all quite useful. 
WHITE FLY 
The injury is minor but their presence is undesirable. 
Either Parathion or DDT will eradicate them. 
Diseases 
BACTERIAL STEM ROT 
In warm weather a rot in the central portion of the 
stem beginning at the base will often cause heavy 
losses. It is most pronounced when the soil is kept un- 
duly moist. Steaming the soil is the best means of con- 
trol. Affected plants should be removed and destroyed. 
BOTRYTIS 
A rot of the petals, particularly on the softer vari- 
eties, is usually caused by the fungus organism known 
as Botrytis or gray mold. The affected area appears 
watersoaked. 
Growth of the organism is favored by high humidity, 
therefore, air circulation is an important means of con- 
trol. Use of heat lines when temperatures warrant or 
fans to move the air are two means of preventing 
growth of Botrytis. Dusting with Parzate or Zerlate is 
also useful. Burn caused by high light intensity may 
appear similar, but it occurs in bright weather, and at 
that time Botrytis is usually not a problem. 
DODDER 
This parasitic plant grows rather freely on chrysan- 
themums and can over-run the crop in a relatively 
short time. Dodder seed lives over winter in the soil 
and after germination, slender yellow-orange colored 
threads twine around the foliage and stems and obtain 
their food from the chrysanthemum. 
Steaming soil will kill the seed. If dodder is found, 
all traces of it must be removed either by hand pick- 
ing or destroying the mums or it will become a very 
serious pest. 
MILDEW 
The familiar white powdery appearance of the upper 
surface of the leaf is indicative that mildew is present. 
Occasionally stems will be affected. Mildew spores 
germinate and grow best in high humidity so air circu- 
lation by means of heat, ventilation, and fans will pre- 
vent or control it. Sulfur is effective but will bleach 
flowers. Mildex is also useful. 
ROOT-KNOT NEMATODE 
As the name implies, small knots are found on the 
root system; affected plants will lack vigor. There is 
no control other than destroying the plants and steam- 
ing the soil. 
RUST 
Small raised areas or blisters appear on the leaves 
or stems and when these break open, brown spores are 
released. Splashing water spreads this organism, so 
keeping the foliage dry and applications of Fermate, 
Zerlate, or Parzate are recommended controls. 
SEPTORIA BLACK SPOT 
Irregular black spots or blotches appear on the foli- 
age particularly when moisture is present. The use of 
Captan, Fermate, Zerlate, or Parzate sprays will con- 
trol this disease organism. 
STEM ROT 
Loss of plants from this trouble is common if the 
cuttings are planted too deep, overwatered, or too 
heavy a soil is used. Drenching the soil with a Fermate 
solution (1lb. per 100 gal.) will kill the organism at the 
soil surface. Shallow planting is recommended. 
STUNT 
Once greatly feared, this virus is now not a serious 
problem. Indexing stock or carefully selecting cuttings 
from presumably healthy plants are the control meas- 
ures that have been used. 
VERTICILLIUM WILT 
Though this fungus organism never kills the plant, it 
causes loss of foliage and vigor so the cut flowers are 
usually rendered unsalable. The organism lives in the 
soil and the plant, so steaming plus the use of cultured 
cuttings will insure a minimum of losses. 
