THE NATIONAL NURSERYMAN 171 
Common name, botan¬ 
ical name, and dura¬ 
tion of life. 
Color, size and arrange¬ 
ment of flowers. 
Sections where in¬ 
jurious. 
Method of seed distri¬ 
bution; vegetative 
propagation of the 
perennials. 
Place of growth and 
products injured. 
Dandelion (Taraxacum 
officinale), P. 
Yellow; 1% inch; head. 
Entire United States. 
Wind; taproot, which 
spreads but little. 
Lawns, meadows, waste 
places; hay and 
lawns. 
Dock, yellow dock, 
sour dock (Rutnex 
arispus), P. 
Green; *4 inch; pan¬ 
icle. 
-do . 
Hay and straw, clover 
and grass seed; tap¬ 
root, which spreads 
but little. 
Hay, small grain, and 
hoed crops. 
Dodder, alfalfa dodder, 
field dodder (Cuscata 
artens is), A. 
Yellow; y 8 inch clus¬ 
ters. 
All clover and alfalfa 
regions. 
Hay, clover, and alfal¬ 
fa seed. 
Clover and alfalfa fields 
Dogbane, Indian hemp 
(Apocynum canna- 
bium), P. 
Greenish white; % 
inch; terminal clus¬ 
ters. 
Upper Mississippi Vay- 
ley. 
Wind; creeping root. 
Fields with sandy soil; 
pasture, grain and 
hoed crops. 
Fern, brake ( Pteridium 
aquilinum) , P. 
No flowers. 
Northwestern States 
and the Pacific coast. 
Spores scattered by 
Wind; running roots. 
Logged-off land, mea¬ 
dows, and pastures. 
Fleabane, horseweed, 
(Erigeron canadensis), 
A 
White; % inch; heads 
in cymes. 
Entire United States. 
Hay, grass and clover 
seeds. 
Meadows, pastures, and 
grain fields. 
Foxtail, yellow foxtail, 
pigeon grass ( Chae- 
tochloa glauca), A. 
Green; spikes . 
.... do . 
% 
Animals, hay, grain, 
and grass seeds. 
Land cultivated in 
early part of season; 
young grass and clo¬ 
ver seedlings. 
Hawkweed, orange 
weed, devil’s paint¬ 
brush (Hieracium au- 
ranticaum), P. 
Orange; 1 inch; heads. 
Maine to Ohio . 
Wind, grass and clover 
seeds; runners sim¬ 
ilar to strawberry. 
Untillable pastures and 
meadows. 
Iron weed ( Verno none- 
boracensis), P. 
Purple; 1-3 inch; heads 
Maine to Maryland and 
Iowa to Kansas. 
Wind ; short thick root¬ 
stocks, making plant 
grow in bunches. 
Pastures and meadows. 
Jimson weed (Batura 
Purple; 3 inches; soli- 
Maine to Minnesota 
Pods and plants blown 
Pastures, barnyards, 
stramonium), A. 
tary. 
and Texas. 
by wind. 
and waste lands; 
seeds, flowers, and 
leaves poisonous. 
Johnson grass (Helens 
halepensis), P. 
Green; y 8 inch; pan¬ 
icle. 
Virginia to Texas and 
California. 
In hay, grain, and 
grass seed; running 
rootstocks. 
All crops except hay. 
Grain fields and hoed 
Lamb’s - quarters, pig¬ 
weed, ( Chenopodiut» 
album), A. 
Green; very small; 
panicle 
Entire United States 
Grain and grass seed. 
crops. 
Lettuce, prickly let¬ 
tuce (Lactuca vvrosa), 
A. 
Milkweed, common 
milkweed (Asclepis sy- 
riaca), P. 
Yellow; 14 inch; heads 
in panicles. 
Ohio to Iowa, Utah to 
California. 
Wind . 
Everywhere; all crops. 
Purple; y 2 inch; um¬ 
bels. 
New York to Minnesota 
Wind; creeping, roots. 
All crops and in pas¬ 
tures. 
Morning-glory (Ipomea 
hederacea), A. 
White, purple, or blue; 
114 inch; solitary. 
New York to Missouri. 
Corn stover, straw, and 
wind. 
Cultivp.ted fields, es¬ 
pecially corn, and 
small grain. 
Mustard, wild mustard 
charlock (Brassica ar- 
vensis), A. 
Yellow; 14 inch; race¬ 
mes. 
Maine to Washington. 
Grain, grass, clover and 
rapeseeds. 
Small-grain fields and 
meadows; grains. 
Nut-grass, coco (Cy- 
perus rotundas), P. 
Brown; 1-16 inch; 
spikelets. 
Maryland to Florida 
and Texas. 
Wind, nursery stock, 
hay, and grass seed; 
tubers. 
All soils; hoed crops. 
Penny cress, French 
weed (Tlilapsi ar- 
vense), A. 
White; y 8 inch; race¬ 
mes. 
North Dakota and 
Minnesota. 
Wind . 
Grain fields and pas¬ 
tures; grain and dairy 
products. 
Pigweed, redroot, care¬ 
less weed (Amaran- 
thus retrofleams), A. 
Green; quite small; 
spikes in panicles. 
Entire United States. 
In grain and grass 
seeds; plants blown 
by wind. 
Plowed land; hoed 
crops. 
Plantain, buckhorn, rib 
grass (Plantago lan¬ 
ceolate) , P. 
White; 1-16 inch; spike 
.... do . 
Hay, clover, and grass 
seed; spreads but 
slowly from a crown. 
Everywhere; meadows, 
pastures, and lawns. 
Poison ivy, poison oak 
(Rhus toxicodendron) 
P. 
Greenish white; % 
inch; panicles. 
Entire United States. 
Does not spread fast by 
seeds; running root¬ 
stocks. 
Moist rich land, along 
fences; poisonous by 
contact. 
Purslane, pusley (Por- 
tulaca oleracea), A. 
Yellow; 14 inch; soli¬ 
tary. 
.... do . 
Tillage implements; 
has a long seeding pe¬ 
riod. 
Rich cultivated land, 
especially gardens; 
hoed crops. 
Quack-grass, witch- 
grass (Agropyron re¬ 
pens), P. 
Green; spike . 
Maine to Pennsylvania 
and Minnesota. 
Seeds of grain and 
coarse grasses; creep¬ 
ing rootstocks. 
All crops on the better 
soils; hoed crops. 
Ragweed, smaller rag¬ 
weed (Ambrosia ela- 
tior), A. 
Yellow; 14 inch; small 
heads on spikes. 
Entire United States. 
Wind carrying matured 
plants; in grain and 
red-clover seeds. 
Everywhere, especially 
grain stubble; hoed 
crops and young grass 
seeding. 
Russian thistle, tumble 
Purplish; 14 inch; soli- 
Minnesota to Washing- 
Wind rolling matured 
Everywhere; small- 
weed (Salsola pesti- 
fer), A. 
tary. 
1 
ton and southward. 
plants. 
grain and hoed crops. 
St. John’s-wort (Hyper- 
Yellow; % inch; 
Maine to North Caro- 
In hay and grass seed; 
Meadows, pastures, and 
icum perforatum) , P. 
cymes. 
lina and Iowa. 
1 rootstocks. 
waste places. 
