SPRAY CALENDAR 93 
Grape Leaf Hopper. Small yellow and red 
marked leaf-hoppers sucking sap from under side 
of leaves. Spray under surface with D-X. 
Black Rot. Causes reddish-brown spots on 
leaves; more rarely on stems; especially bad in 
rotting the berries, which finally become hard, 
shrunken and wrinkled black mummies. This is 
one of the worst diseases of the grape, and often 
dificult to control by spraying, which must be 
thorough, especially the first season. Begin spray- 
ing before blossoming time, about the last of May, 
with a second application just after blossoming 
and subsequent sprayings at intervals of about 
ten to fourteen days. Use Bordeaux up to the 
last of July; usually four or five sprayings with 
Bordeaux are sufficient. 
HOLLYHOCK 
Rust. Appears as small, compact, reddish-brown 
outbreaks on leaves and stems. After their death 
in fall, cut off the plants close to the ground, care- 
fully gather up these and any rubbish that may 
contain spores and destroy them. Spraying with 
Bordeaux is recommended by some as helpful in 
checking the rust; begin as plants push through 
the ground. 
MAPLE 
Maple Borer. Larva tunnels in spiral course up- 
ward around trunk or larger branches of sugar 
maple, working in sapwood and cambium, often 
girdling the trees. Examine trees in September 
for sawdust. Find the burrow, inject Borerkill 
and plug the opening. 
Woolly Maple Leaf Scale. Cottony or woolly 
masses of wax, containing the females, eggs and 
sometimes larvae, appear on the under side of the 
leaves in midsummer; insects suck out the sap, 
causing leaves to fall prematurely. Males and 
larvae enter crevices of bark of trunk and branch- 
es; larvae make cases here and pass the winter. 
Attacks only sugar maples. Spray dormant trees 
with nicotine solution and soap. Burn all infested 
leaves. 
Cottony Maple Scale. Large, oval, brown, soft 
scales on back of branches of silver and red ma- 
ples. Each scale in early summer develops a large 
cotton-like tuft of wax nearly half an inch long, 
and soon after the young appear. Spray with 
Scalecide or Sunoco when dormant. 
MUSK MELON 
Melon Aphid. Sucks the sap from the under 
side of the leaves and, when abundant, causes 
much damage. Underspray the leaves with nico- 
tine solution, D-X or Red Arrow. 
Striped Cucumber Beetle. See Cucumber. 
NASTURTIUM 
Aphid. Brown aphids cluster on stems and 
leaves, sucking the sap. Spray with nicotine solu- 
tion, D-X or Red Arrow. 
ONION 
Thrips or “White Blast.” Very small insects 
which feed upon the surface of the leaves, giving 
the field a whitish appearance. Burn all tops and 
refuse; burn over the grass land around the field 
to kill over-wintering insects. Spray with nicotine 
solution or Red Arrow. 
PEA 
Green Pea Aphid. Attacks the plants early in 
June and sucks up the sap from the leaves and stems, 
often causing great injury. Early peas may ma- 
ture a crop before aphis injures them. Spray 
vines with D-X, Red Arrow or Rotenone Spray. 
POTATO 
Flea Beetle. Small black jumping beetles eat 
holes through the leaves. Spray or dust upper 
and under surfaces with Rotenone or Cryolite. 
Colorado Beetle. Adults and larvae devour the 
leaves. Spray with lead ar- 
senate as soon as injury is 
apparent. May be used in 
Bordeaux mixture. 
Three-Lined Potato Beetle. 
Larvae feed upon the leaves 
and carry their black excre- 
ment on their backs. Spray 
with lead arsenate. 
Stalk Borer. Larvae tun- 
nels inside the stalk. Burn 
infected vines. 
Potato Aphid. Green aphids 
appearing in large numbers 
suck the sap from shoots and 
stems, causing much damage. 
Spray with nicotine solution, 
D-X or Red Arrow. 
Blight or Downy Mildew. 
Causes a sudden blackening of the leaves, and 
often death to the vines, from July to September, 
in moist seasons; usually shows a slight whitish 
growth of fungus on the under side of leaves; rots 
tubers. Spray with Bordeaux before the trouble 
appears about July lst, and keep vines well covered 
to the end of the season. Three to five sprayings 
by hand to five to seven by power sprayer are 
necessary. After last cultivation thoroughly ridge 
up the rows to help keep the spores from washing 
down the tubers. Early varieties often escape 
blight by maturing before its appearance. 
Scab. Produces the common scabby appearance 
on surface of tubers. Soak seed tubers one and 
one-half hours in formalin (formula B). Formalin 
fumes are often used when large quantities are 
treated. Care in filling space sufficiently, however, 
is necessary to avoid injury by “pitting” from 
absorbtion of fumes. Avoid planting on infected 
land by systematic rotation. The use of lime, 
wood ashes, and various barnyard manures will 
increase the amount of scab. The same trouble 
occurs on beets and turnips. 

Potato Beetle 
ROSE 
Rose Slug. Eats away the green portions of the 
leaves. Spray with D-X or Red Arrow or Triogen. 
Aphid or Green Fly. Suck sap from the leaves 
and stems. Spray with Nicotine solution, Red Ar- 
row or Triogen. 
Mildew. Develops a white powdery or cob-web- 
like growth on the young leaves, which become 
more or less distorted and fall off. Tea roses 
especially susceptible. Treat same as for leaf 
blotch or dust with wettable sulphur; be care- 
ful in airing greenhouses. 
SQUASH—PUMPKIN 
Squash Lady Beetle. Both adults and larvae 
devour the leaves. Spray with lead arsenate and 
Dax 
Striped Cucumber Beetle. See Cucumber. 
Squash Bug or “Stink Bug.” A brown bug three- 
fourths of an inch long sucks the sap from the 
under side of the leaves, causing them to wilt and 
die.. Ask for special information. 
