Vol. 15—1961 - NorthEastern Weed Science Society

yielded as much as the check plots; 19.06 and 18.56 tons per acre, respectively. ,-"".'
The same treatments on the Collington loam soil did not injure the plants.
Lay-By. Eptam was the only herbicide in the lay-by experiments that received
a score of 4.0 or better on both soils fo,r the control of grasses and broadleaf
weeds, Table 4. The rating of 4.0 was considered for thp,t time of season to
be the threshold 1eyel of commercial acceptance.
Amiben afforded good weed growth suppression on the Collington loam
soil but was not effective on the Downer loamy sand. The loss in efficiency
on the sandy soil may have been the result of a carrier x moisture interaction.
There was no rain for 10 days after herbicide application. Weeds, primarily
crabgrass, became established during this period.
Neburon, Solan and Zytronat the rates employed were not effective
lay-by herbicides for prOCeS51.ng tomato fields in which the chief natural plant
competitors were grasses. All of the materials were rated equal in control of
broadleaf weeds.
Neither yields, color nor acidity were affected by any of the lay-by
herbicide treatment~, ,Table 5.
Table 4
Effect of Lay-By Herbicide Treatment on Late
Season Weed Control in Tomato Fields on Two Soil Types
Downer Loamy Fine Sand Collington Fine Sandy Loam
Treatment Grass Broadleaf Grass Broadleaf
Mean Control
Dactbal applied at rate of 8 pounds per acre June 3 in the Collington
post-transplanting plot test resulted·in better weed control than 12 pounds
applied at lay-by, July 19. Reasons for this behavior were not readily apparent.
Rating*­
Check 1.0 3.1 1.0 3.9
Amiben 3.1 3.9 4.1 4.3
Dacthal 4.5 4.1 2.9 3.2
Eptam 4.8 4.0 4.4 4.2
Neburon 1.0 3.9 1.3 4.2
Solan 1.0 4.5 1.3 4.2
Zytrol 2.2 3.7
LSD •05 0.8 N.S• 1.0 N.S.
.01 1.1 1.5
* 1 - no control, 5 - excellent control.
Rating of 4.0 or higher would be commercially acceptable for the
rating period.