Summary: The uptake, translocation and metabolism of glyphosate [N‐(phosphonomethyl) glycine] by Canada thistle (Cirsium arvense (L.) Scop.) (susceptible) and leafy spurge (Euphorbia esula (L.)) (resistant) were examined in an attempt to elucidate the nature of the differential sensitivity. The pattern of uptake and translocation was similar in both species. Glyphosate moved readily in the apoplast and the symplast. High humidity and/or surfactant greatly increased the amount of 14C‐glyphosate absorbed and translocated over that in low humidity and/or without surfactant. No 14Cmetabolites were detected in either species 1 week after treatment with 14C‐glyphosate. More of a glyphosate spray solution containing a fluorescent dye was received and retained on Canada thistle by virtue of its growth habit than on leafy spurge. More glyphosate should therefore be available for uptake by Canada thistle and this may account for the differential sensitivity of these two species.

Silverberry (Elaeagnus commutata Bernh.) is of some importance as an ornamental shrub and in certain areas is a rangeland weed. Various germination tests over a 2-year period showed that unstratified seeds of this species, within intact endocarps, germinated 0 to 20% in 10 days, and 0 to 45% within 20 days, on moist filter paper in Petri dishes in the dark at 20 °C. After stratification of such seed in moist sand at 5 °C, for periods of 40 to 110 days, the germination percentages ranged from about 23% to 75% respectively. Removal of the endocarps, however, from unstratified seeds resulted in 85 to 100% germination within 10 days. A water-soluble extract from the endocarps retarded growth of wheat seedlings and of seedlings from naked silverberry seeds but did not reduce percentage germination. Self-controlled embryo dormancy is apparently not a major factor causing delayed germination of the silverberry.Supplementary tests involving heat treatments, or soaking of the unstratified fruits in gibberellin or KNO3 solutions, were without effect on germination of silverberry seed from within its endocarp.

Yields of marsh reed grass from plots in a native wet-meadow cut two to seven times per summer were reduced in relation to yields of plots cut only once at the end of the season, by 15 to 20 per cent with two to four cuttings, by 35 to 45 per cent with five to six cuttings and about 70 per cent by seven cuttings. Fertilizer applications (200 lb./ac., 16-20-0), during the 2 final years of the 3-year study, increased dry matter from recipient plots cur less than five times in 1960, and from all fertilized plots during 1961. Percentage nitrogen declined progressively in forage of first cuttings from June to September but not in the bi-weekly re-growths. There was no appreciable difference in percentage nitrogen attributable to fertilizer but pounds of nitrogen per acre in forage from fertilized plots exceeded the controls, plots harvested for the first time near the end of June and again at the end of the season being greatest in this respect. Fertilizer increased percentage ether extract slightly, approximately doubled the percentage phosphorus, and had no effect on percentage crude fiber and calcium in the samples tested. Percentages of chemical constituents compared favorably with reported data for upland species.

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