Soil-residual Herbicides Research Articles

Between-Row Mowing + Banded Herbicide to Control Annual Weeds and Reduce Herbicide Use in No-till Soybean (Glycine max) and Corn (Zea mays)1

Abstract: Alternative methods are needed to control weeds in no-till corn and soybean which minimize herbicide contamination of surface or ground water. The objective of this research was to determine whether between-row (BR) mowing + band-applied herbicide could help reduce herbicide use, without sacrificing summer annual weed control or yield, in no-till soybean and field corn. Glyphosate was applied shortly before or at planting to control emerged winter annual weeds in all treatments. In the BR mowing weed management system, the band-applied soil residual herbicides imazaquin + alachlor in soybean or atrazine + alachlor in corn were applied shortly before or after planting followed by two or more between-row mowings to control summer annual weeds. Annual weeds were first mowed when they were about 8 cm tall and again just before crop canopy closure. Between-row mowing weeds very close to the soil surface two or three times killed or suppressed summer annual grass and broadleaf weeds, chiefly giant fox...

Evaluation of Herbicides for Phytotoxicity to Rose Plants and Efficacy

Abstract Roses frequently occur in gardens and landscapes and may require weed management. Herbicide trials were conducted with 10 herbicides applied at label rates to plots containing a hybrid tea rose cultivar. The primary objective was to evaluate injury to rose plants when herbicides were sprayed over-the-top at two stages of growth: bud break and full leaf. A secondary objective was to evaluate the efficacy of the herbicides. The soil residual (pre-emergent) herbicides Devrinol (napropamide), Goal (oxyfluorfen) and the dinitroaniline herbicides Surflan (oryzalin), Treflan (trifluralin) and Prowl (pendimethalin) did not injure roses when applied at bud break. The herbicides Ornamec (fluazifop-p-butyl), Poast (sethoxy dim) and Envoy (clethodim), which have post-emergent activity, also did not injure roses when applied to roses at bud break or when applied in late spring when plants had fully developed leaves. Roses oversprayed at bud break with the herbicides Roundup (glyphosate) and Trimec Classic (2,4-D + MCPA + dicamba) did not show phytotoxicity symptoms immediately after application but had significantly shorter shoots beginning six weeks after treatment (WAT). Roses with fully developed leaves which were oversprayed with Roundup and Trimec Classic did show symptoms of injury one WAT and thereafter.

The effects of alternatives to soil residual herbicides on weed control, yield and quality of hops

SummarySeveral non-chemical methods of weed control in hops (Humulus lupulus) were evaluated in a three-year study. The results show that the use of cultivation, grass and winter rye cover crops, straw and plastic mulches all gave satisfactory weed control in both alleyways and hop rows. Data are presented on the effects of the main treatment groups, on the yield, alpha-acid content and alpha yield of hops. The effects on other hop cone quality criteria are also reported. Cultivation to control weeds had to be timely, and by the end of the study, numbers of weeds germinating in the spring were increasing. The use of a winter rye cover crop was successful in reducing over-wintering weed populations in cultivated plots. Grass reduced yield but raised the alpha-acid content of the cones, resulting in no overall loss in yield of alpha-acid. Yield reductions were overcome by adding extra nitrogen as an early spring top dressing, but this tended to reduce alpha-acid content to give similar alpha yields. Analysis of soil mineral nitrogen contents of soils to 90 cm depth in spring and autumn indicated that extra spring nitrogen was readily taken up by grass swards, helping to overcome its competitive effect on the hop plants. Winter rye reduced soil mineral nitrogen levels although this failed to reach statistical significance (P>0.05) but this nitrogen was returned to the soil when the cover was cultivated out in spring. Straw mulches tended to raise alpha-acid levels enough to raise alpha yield one year by 5% compared with conventional residual herbicide, although this failed to reach statistical significance (P>0.05). The implications of the results to growers of hops are discussed.

French tarragon (Artemisia dracunculus): tolerance to some soil-residual herbicides

Abstract The tolerance of newly planted French tarragon (Artemisia dracunculus L.) to 10 soil-residual herbicides was evaluated in Canterbury in 1984–85. The survival of the plants and yield of the crop was unaffected by methabenzthiazuron up to 4.2 kg ha-1, metribuzin up to 1.8 kg ha-1, and diuron up to 4.8 kg ha1. These herbicides could form the basis of weed control programmes for French tarragon at establishment. Tarragon transplants did not tolerate bromacil, terbacil, chlorthiamid, dichlobenil, oryzalin, oxadiazon, and simazine at herbicidally effective rates.

The use of soil-residual herbicides on recently planted leucadendrom ""Safari Sunset""

The use of soil-residual herbicides on recently planted leucadendrom ""Safari Sunset""

Repeated Application of Soil-residual Herbicides and Yield and Quality of ‘Valencia’ Oranges1

Abstract The repeated application of simazine, diuron, bromacil, and a diuron-bromacil mixture over a 5-year period had no significant effects on yield or fruit quality characteristics of ‘Valencia’ oranges.

Pre-emergence Weed Control in Young Deciduous Fruit Trees1

Abstract A number of pre-emergence soil residual herbicides were tested at 2 locations on varieties of young peach, plum, cherry, pear and walnut rootstocks. The greatest variation in response resulted from differences in location. Important differences in varietal response were also obtained with the various herbicides in light soils. Simazine appeared sufficiently safe to trees in heavier soil but gave variable weed control. Diuron gave about the same degree of weed control but more safety than simazine on young trees. Of the uracil herbicides tested, DP-733 was the least toxic to the fruit tree species tested, while bromacil and isocil were generally the most toxic, except to peach trees. Of the commercial uracil herbicides, only DP-732 (terbacil) was of sufficient interest for further study.