Vol. 15—1961 - NorthEastern Weed Science Society

358.
The 2,4,5-TP was most effective in controlling the weed species present.
At rates of 1/2 and 1.0 pound per acre, 2,4,5-TP effectively contro.ll~d;
White Cockle (Lychnls !.!2!), Grass-leaved Stitchwort (Stellariaramihea),
Cinquefoil (Potentilla ,recta), Daisy Fleabane (Er!seron canadensis , Bull
Thist~~ ~:(Cir81U!1~ceolatum), and Ox-eye Daisy (Chrlsanthemum leucanthemum).
Poor control wasotained on Chicory (Cichorium intybus)( Dandelion (Taraxacum
officinale), Narrow-leaved Plantain (PlantagO lanceolata) and Curled Dock
(Rumex crispus).
The amine and ester formulations of 4(2,4-DB) resulted in poor control
of the weed species present.
i
The averase yield for each treatment on alfalfa and birdsfoot trefoil
are shown in Table I.
Table I. The Effect of Spring Applied Herbicides on the Yield of
Established Alfalfa and Birdsfoot 'f:refoil.
1959
Av. Yield in T/A. of Forage*
Treatment
First Cutting, 1959
-:No. Chemical Rate/A.
, Alt~fa Birds foot
Used Lbe. A.E. Trefoil
'1 4 2,4-DBj_ amine
2 4 2, 4..DB - amine
:; 4 2, 4-DBamine
4 4 2,4-DB) ester
5 4 2,4-DB) ester
6 42,4~DB) ester
7 - 2,4,5-TP ester
8 - 2,4,5-TP ester
9 2,4,5-TP ester
10 Check
1
2
3
1
2
3
1/4
1/2
1
o
1.33
1.47
1.26
1.39
1.41
1.28
1.09
0·99
0·97
1.37
1.05
1.14
1.02
1.20
1.20
1.05
1.19
1.17
1.04
0·97
*Average of 4 replicated
plots.
SUMMARY:
Due to the initial injury and reduced growth of alfalfa
and birdsfoot
trefoil, spring treatments on- established stands do not look promising. A
preliminary summary of data from studies initiated in, the spring of 1960 and
other work in connection With weed control in birdsf'oot trefoil. seed production
areas show similar results to those ~ported in this paper.
~: A mimeographed copy of' complete pa.per is a.vailable from the author.