Selective Herbicidal Control of Barley Grass in Pasture and Lucerne

Abstract

Comparative experimental re.sults with dalapon-sodium and paraquat for the control of barley grass {Hordeum leporinum Link) in lucerne and subterranean clover pasture are reported. Sprays were applied 3-4 days after a simulated grazing..\t all rates tested (1-4 Ib/ac), dalapon provided satisfactory control of, but did not eradicate, barley grass. Subterranean clover productivity was reduced substantially whether application was in May or July; lucerne growth was retarded by 4 Ib/ac applieti in July.Paraquat applied at 0-06-0-25 Ib/ac in May gave similar bul somewhat less effective control than did dalapon. Some re-establishment of barley grass occurred as a result of late germinations following the May applications. Paraquat applied in July ai 0-06 Ib/ae gave unsatisfactory results, bui at 0-12 and 0-25 Ib/ac the control was comparable with that given by dalapon. Subterranean clover was damaged slightly by the May treatments but recovered quickly, after initial scorching, following applications in July. Lucerne was neither damaged nor retarded by paraquat.The addition of a wetting agent increased the efficacy of paraquat in controlling certain more tolerant annual grasses, but not barley grass. Dhherbage sHeclif des pdtures el des luzerrus: lutU conlre I'orge des liivresResume. L'auteur rapporte les rdsultats obtenus dans des experiences mettant en comparaison le dalapon sel de sodium et le paraquat pour la luite contre I'orge des liivres {Hordeum leporinum Link] dans la luzenie et des paturages de trifle souterrain. Les traitements ont ^te appHqu^s 3-4 jours apr^s une pature simul^e.A toutes les doses essayees (1,1^,4 kg/ha) le dalapon a donnd un d^sherbage satisfaisant mais pas une destruction complete de I'orge des iievres. La productivite du trcfle souterrain fut notablement r^uite, que le traitement ait 6i6 effectu^ en mai ou en juillet; la croissance de la luzeme fut relardee par une dose de 4,4 kg/ha appliquie en juillet.La paraquat appHqu^ de 0,07 k 0,28 kg/ha en mai, donna des rtsultats similaires bien que l^g^rement infdrieurs a ceux obtenus avec le dalapon.Une r^infestation d'orge des Iievres fut observ^e, resultant des germinations apr^s les traitements de mai. Le paraquat appliqu^ en juillet a 0,07 kg/ha ne donna pas de r^sultats satisfaisants, mais & 0,13 et 0,28 kg/ha le d^sherbage fut comparable k celui obtenu avec le dalapon.Le trefle souterrain fut endommage Increment par les traitements de mai; il r^cuptfra rapidement apr^s une reaction initiate, a la suite des applications en juillet. La luzerne ne fut ni endommag^e ni retardde par le paraquat.L'addition d'un mouillant aecrut I'efficacild du paraquat contre certaines gramin^es annuelles moins sensibles, mais pas contre I'orge des Iievres. Bekampfung von Hordeum leporinum auf Weiden und in Luzeme Zusammenfassung. Es wird tiber Versuche zur Bekampfung von Hordeum leporinum Link in Luzerne und auf Weiden mit Paraquat und dem Natriumsalz des Dalapon berichtet. Gespritzt wurde drei bis vier Tage nach simulierter Beweidung. Bei alien untersucbten Au...

The Chemical Control of Barley Grass in Dryland Lucerne

“…Subterranean clover and burr medic persisted in the paraquat and dalapon treatments but persistency and production decreased with increases in the rate of applieation. This is in agreement with the findings of Campbell (1961), Bramley (1961) and Cuthbertson (1964). Paraquat at 0-56 kg/ha killed many subterranean clover seedlings.…”

“…The degree of control was dependent upon herbicide and rate of application. This is in agreement with the results obtained by Squires (1963) and Cuthbertson (1964) with paraquat and dalapon on irrigated clover and lucerne pastures respectively and Squires & Rogers (1964) with paraquat on lucerne. At the doses used, paraquat and diuron caused the least reduction in the total herbage dry-matter yield.…”

“…The selective control of barley grass by dalapon, paraquat and diquat in lucerne is reported in Australia (Cuthbertson, 1964;Squires & Rogers, 1964;Tickner, 1968), Control was satisfactory but the grass was not eradicated. Campbell (1961) reported the control of barley grass with dalapon in a medic pasture although pasture growth was reduced substantially.…”

“…Campbell (1961) reported the control of barley grass with dalapon in a medic pasture although pasture growth was reduced substantially. In New Zealand and Australia barley grass has been selectively controlled with dalapon in white clover (Lynch, 1955;Merry, 1959;Squires, 1963); however, the herbicide caused severe damage to subterranean clover when used at a rate which eontrolled the grass (Squires, 1963;Cuthbertson, 1964),…”

Effects of Grazing Management on Natural Pastures in a Marginal Area of Southeastern Australia

“…These include spraying with herbicides (Collins, 1955;Squires, 1963;Cuthbertson, 1964) and mechanically removing seed heads by mowing. Eradication may be warranted in New Zealand (Thompson, 1962;Meeklah, 1964) or in the higher rainfall areas of southeastern Australia, where it can be followed by oversowing with improved species, such as subterranean clover (Trifolium subterraneum)-annual ryegrass (Lolium rigidum) pastures.…”