RAB 
GRASS 
CONTROL 
Means who come in to discuss crab 
grass look askance when we tell them 
grass is the best control we know. 
Nevertheless no better means for 
eliminating crab grass can be exhib- 
ited than a well-established, properly 
nurtured lawn of permanent grasses. 
Most lawn soils are infested with 
crab grass seeds. A dense turf which 
shades the ground will effectively 
discourage seed germination. The 
mild shade of the ideal lawn, free of 
crab grass, illustrates our point. 
When turf is thin or dies out from 
disease, grubs or insect damage, crab 
grass and other weeds quickly volun- 
teer to fill the void. 
Unfortunately, most of us think 
of remedial measures for crab grass 
eradication when the season is so 
advanced that little can be accom- 
plished toward the desired end. Early 
July and no later than August first 
is the time control measures must 
begin. A choice of several methods 
or chemicals to effectuate control are 
open to you. 
If only occasional plants occur, 
hand removal is practical. When in- 
festation is heavy, repeated heavy 
rakings to lift runners, followed by 
cutting to prevent seed head forma- 
tion will succeed, if the lawn is liber- 
ally fertilized and reseeded in early 
September. The fertilization and re- 
seeding should be preceded by spik- 
ing to insure a good seed bed. 
Another method used to a limited 
extent is to shade the areas of crab 
grass with burlap or black roofing 
paper. The theory of this practice is 
based on the sensitiveness of crab 
grass to shade and the tolerance of 

permanent lawn grass. Generally six 
to nine days of dense shading will 
kill the crab grass but blue grass 
while extremely yellowed and: chlor- 
otic, will often recover. Our own ex- 
periments with this method lead us 
to believe it works somewhat better 
in theory than in practice. 
Several chemicals have been em- 
ployed in recent years in the eradica- 
tion programs with highly satisfac- 
tory results. Sodium chlorate, so- 
dium arsenite and arsenic acid have 
all been successfully used. The latter 
two have proven most satisfactory. 
They are the active ingredients in a 
number of trademarked materials 
and may be purchased as such in 
commercial grades for direct appli- 
cation with dry carriers or made up 
into liquids for spray application. 
ZOTOX, a liquid, has been widely 
used. MILARSENITE, a combina- 
tion of milorganite and sodium arsen- 
ite is another excellent product. All 
of these materials are extremely caus- 
tic to all forms of plant life. Discol- 
oration to desirable grasses is always 
quite severe and frequently bents and - 
fescues perish. None are selective to 
the extent that crab grass and weeds 
are killed, leaving permanent grasses 
intact. Less caustic action on perma- 
nent grasses is based on the narrower 
leaf surface as compared to crab grass 
and other weeds. Soil moisture and 
temperature also affect the action of 
these chemicals. Burning is accen- 
tuated materially when temperatures 
are above 70 degrees and when soil 
moisture is deficient. 
ZOTOX 
The liquid chemical, which kills both 
the plant and immature seeds of crab 
grass and checks re-infestation. Al- 
though it does discolor permanent 
grasses very markedly, they will recover 
if the application has been made at 
proper strength. 
The burned crab grass plants need 
not be raked out, but if thoroughly 
spiked and chopped, make a good bed 
for the new seed and fertilizer. 16-oz. 
bottle treats 2000 sq. ft. 
8 ozs., $1.00; 16 ozs., $1.50; 32 ozs., 
$2.50; 5 Ibs., $4.50. 
[6] 

MILARSENITE 
A combination of Milorganite, the 
popular lawn fertilizer, and sodium 
arsenite, together with conditioners 
and activating agents. The best ma- 
terial to use whén considerable per- 
manent grass is present, especially 
Kentucky Blue Grass. While sodium 
arsenite, used dry, or in liquid, is ex- 
tremely caustic, it is less so in the dry 
form. This preparation has the added 
advantage of supplying a stimulant 
for the grass, once the initial burning 
effect is past. In the course of sev- 
eral applications, which we recom- 
mend, considerable plant food is 
added to the soil, encouraging quick 
recovery of existing permanent 
grasses and a fast start to that newly ' 
seeded. 
Rates of application for MILAR- 
SENITE vary with conditions, but 
ordinarily two to three applications 
involving a total of about 30 lbs. per 
1000 sq. ft., will suffice. Uniform 
application is essential and this is best 
accomplished by renting a precision 
distributor, properly calibrated, to 
apply the recommended quantities 
for treatment. These spreaders, which 
should not be confused with the ordi- 
nary home lawn fertilizer distribu- 
tors, are available at a nominal 
charge. Their-cost is $75.00, which 
is too much to invest in a unit re- 
ceiving only occasional use on the 
home grounds. 
Prices of Milarsenite: 25  I|bs., 
$2.50; 50 Ibs., $3.75; 100 lbs., $7.00; 
500 Ibs., $33.00. 
SODIUM ARSENITE (Dry) 
Sodium Arsenite is one of the principal 
chemicals used in the preparation of many 
weed killing compounds. When the lawn 
is solidly infested with crab grass we gen- 
erally recommend spraying the area with 
a sodium arsenite solution which can be 
easily made up from the dry chemical. 
With most compressed air sprayers, it re- 
quires about five gallons of solution to 
cover 1000 sq. ft. of lawn surface. Eight 
to ten ounces of dry sodium arsenite is 
needed for 1000 sq. ft. 
1 Ib., 50c; 5 Ibs., $2.00. 
