8 BULLETIN 1387, U. S. DEPARTMENT OF AGRICULTURE 
inclusive. In 1921 the land was fallowed. The 1922 crop, therefore, 
was the ninth rice crop in 10 years; the 1923 crop was the tenth rice 
crop in 11 years; and the 1924 crop was the eleventh rice crop on 
this land in 12 years. In the spring of 1922 the fallow land was dou- 
ble disked, harrowed, and dragged. For the 1923 crop the land was 
spring plowed, harrowed, and dragged. In preparation for the 1924 
crop the land was winter plowed and the following spring double 
disked and dragged. Each year these tillage operations provided a 
reasonably good seed bed, but in the spring of 1924 considerable 
water grass was present from seed which had been germinated by 
the early spring rains. Many of these plants were not killed by 
double disking, and when the rice was sown and submerged a good 
deal of this grass was too large to be suffocated by water, and there- 
fore it continued to grow with the rice crop. 
EFFECT OF SOWING BROADCAST OX THE SOIL 
In the experiments on the effect of sowing broadcast the rice 
was sown on the soil on different dates and the plats immediately 
submerged to the required depths. On plats submerged 2 inches 
considerable water grass emerged; on plats submerged 4 inches some 
water grass emerged; but plats submerged 6 and 8 inches were prac- 
tically free from water grass and sprangletop (LeptocMoafascicularis) 
each year. Other water weeds appear to grow about equally well 
at all depths of submergence. The same effect on water grass was 
noted for all dates of seeding. However, on late-sown plats seepage 
started growth of barnyard grass before the rice was sown and the 
plats submerged, and these plats had more grass and poorer stands 
each year than those not affected by seepage. Scum also is more 
troublesome with late-sown rice. 
EFFECT OF SOWING BROADCAST IN THE WATER 
The effect of sowing broadcast was compared with other methods 
of sowing. In this experiment the plats were submerged on May 16 
to the required depths and the rice was then sown broadcast in the 
water. The effect on water-grass control was the same in this ex- 
periment as when the rice was sown broadcast on the soil and the 
land immediately submerged. However, less seed usually is required 
to obtain good stands when rice is sown broadcast in the water than 
when it is sown broadcast and then submerged, and a certain quan- 
tity of seed is also saved by protection from birds, but the increased 
cost of seeding in the water will likely more than offset such saving 
of seed. 
EFFECT OF DRILLING SEED 
On these plats the rice was drilled about 1 to 1 x /i inches deep and 
immediately submerged to a depth of 6 inches. The water grass was 
effectively controlled, but poor stands and comparatively low yields 
of rice were obtained. It was observed on these plats and on other 
plats with thin stands of rice that redstem (Ammannia coccinea)> 
annual sedge (Cyperus difformis), and cat-tail (Typhalatifolia) were 
often present. When these weeds make much growth they reduce 
the yields of rice. 
