At least two weedings within the first 5 weeks after sowing are necessary to minimize yield reduction caused by weeds in cowpea [Vigna unguiculata (L.) Walp.]. During a 3-yr study, a preemergence application of metolachlor [2-chloro-N-(2-ethyl-6-methylphenyl)-N-(2-methoxy-1-methylethyl)acetamide] at 2.0 to 3.0 kg/ha, DCPA (dimethyl tetrachloroterephthalate) at 10.0 kg/ha, or pendimethalin [N-(1-ethylpropyl)-3,4-dimethyl-2,6-dinitrobenzenamine] at 2.0 or 2.5 kg/ha controlled most annual grasses effectively. Itchgrass (Rottboellia exaltata L.) was controlled with pendimethalin at 2.5 kg/ha, but metolachlor had no effect on this weed. These herbicides caused no crop injury and cowpea grain yield was as good as in the handweeded and weed-free plots. Alachlor [2-chloro-2′, 6′-diethyl-N-(methoxymethyl) acetanilide] applied preemergence at 2.0 kg/ha was effective against annual weeds, but was phytotoxic to cowpea.

Oxadiazon [2-tert-butyl-4(2,4-dichloro-5-isopropoxyphenyl)-Δ2-1,3,4-oxadiazolin-5-one] at 2.2 to 4.4 kg/ha controlled goosegrass [Eleusine indica (L.) Gaertn.] without injuring bermudagrass [Cynodon dactylon (L.) Pers.], but severely injured overseeded common ryegrass (Lolium multiflorum Lam. common) and perennial ryegrass (Lolium perenne L. ‘Medalist VI′) for a 5 – to 6-week period after treatment in the spring and thus reduced turf quality. The transition was poor because ryegrass was killed faster than bermudagrass could initiate new spring growth. The combination of bensulide [O, O-diisopropyl phosphorodithioate S-ester with N-(2-mercaptoethyl)benzenesulfonamide] and oxadiazon applied as a single treatment at 6.7 + 1.7 kg/ha controlled goosegrass as effectively as did oxadiazon applied alone at 2.2 kg/ha or higher rates and did not injure the turf, so the transition from cool-season grass to bermudagrass was uniform. Aeration of an overseeded bermudagrass turf after applications of oxadiazon did not significantly decrease goosegrass control.

Burs of common cocklebur (Xanthium strumarium L.) obtained from Stoneville, Mississippi; Urbana, Illinois; and Lamberton, Minnesota, were used in greenhouse and growth chamber studies. The Mississippi and the Illinois strains were both classified as being in the “strumarium” complex of X. strumarium, whereas, the Minnesota strain was classified as being in the “hybrid” complex. The Minnesota common cocklebur developed branch leaves in the leaf axils of the main stem to a much greater extent than did the Mississippi and Illinois common cocklebur. The Mississippi common cocklebur was frequently more tolerant of postemergence applications of bentazon [3-isopropyl-1H-2,1,3-benzothiadiazin-4(3H)-one 2,2-dioxide] than were the Illinois and Minnesota common cockebur. The Mississippi and Illinois common cocklebur developed leaf necrosis when sprayed with an insecticide formulation containing malathion (o, o-dimethyl phosphorodithioate of mercaptosuccinate) and petroleum solvents; the Minnesota common cocklebur did not.

‘Tracy′, ‘Tracy-M′, and ‘Centennial′, soybean [Glycine max (L.) Merr.] cultivars were evaluated under greenhouse and field conditions for their tolerance to metribuzin [4-amino-6-tert-butyl-3-(methylthio)-as-triazin-5 (4H)-one]. The I50 (50% injury) concentration of metribuzin, as determined in nutrient culture, for Tracy-M was more than three times the I50 for Tracy, but was equivalent to the I50 for Centennial. Data from greenhouse and field studies on Sharkey clay and Dundee silt loam soils indicated that Tracy-M was more tolerant to metribuzin than its parent selection, Tracy, but no more tolerant than Centennial when metribuzin was applied preplant soil incorporated or surface preemergence alone or in combination with several dinitroaniline herbicides.

Five field experiments were conducted to evaluate effectiveness of postemergence herbicidal treatments. Amitrole (3-amino-s-triazole) at 1.1 kg ai/ha and picloram (4-amino-3,5,6-trichloropicolinic acid) at 0.6 kg ai/ha reduced stands of common milkweed (Asclepias syriaca L.) for a 4-yr period. Glyphosate [N-(phosphonomethyl)glycine] at 2.2 kg ai/ha reduced stands of milkweed for two to three growing seasons. Glyphosate or amitrole applied in June (early bud stage) more effectively reduced milkweed stands in the second year than did the herbicides when applied in August (post-flowering stage). Treatments of 2,4-D [(2,4-dichlorophenoxy)acetic acid], 2,4,5-T [(2,4,5-trichlorophenoxy)acetic acid], and dicamba (3,6-dichloro-o-anisic acid) did not reduce stands of common milkweed.

The anatomy of the husk (lemma and palea) and caryopsis coat (pericarp, seed coat or testa, and nucellar epidermis) of a typical mature wild oat (Avena fatua L.) caryopsis was investigated using both scanning electron microscopy and light microscopy. Both the lemma and palea consist of very thick-walled, lignified cells. In section, the lemma appears almost twice as thick as the palea. The pericarp is comprised of only one or two layers of relatively thin-walled cells and is closely appressed to the underlying seed coat over most of the grain. Both the outer seed-coat cuticle and the inner cuticle are present over almost the entire caryopsis and are continuous with the pigment strand that occurs deep in the crease region of the grain. The only discontinuities in the seed coat are at the basal end of the grain near the embryo. In the dorsal region of the caryopsis, the outer cuticle is approximately 3.5 μm in thickness, whereas the inner cuticle is less than 1 μm in thickness. Where the two pass over the embryo they are much thinner, with the inner cuticle becoming almost indistinguishable in places. The remains of the nucellar epidermis are tightly amalgamated to the seed coat and outer tangential walls of the underlying aleurone cells, which are clearly distinguishable by their large size and characteristic appearance.

Saltcedar (Tamarix pentandra Pall.) and Russian olive (Elaeagnus angustifolia L.) invade moist pastures and rangeland and cause serious forage-production and soil-water losses. Our objective was to develop criteria for classifying sites relative to the likelihood of infestation by saltcedar and Russian olive, based on comparisons of soil and vegetation characteristics of infested and adjacent uninfested sites. Discriminant analyses indicated that Russian olive occurs on soils with low to medium concentrations of soluble salts (100–3500 ppm), whereas saltcedar occurs on soils with much higher soluble salt concentrations (700–15000 ppm). Characteristics of the herbaceous vegetation on sites infested with saltcedar or Russian olive differed distinctly from each other and from adjacent, uninfested sites. Frequency of occurrence of certain herbaceous understory species provided the most accurate basis for discrimination of infested and uninfested areas. Discriminant analysis may be of value in the development of infestation-proneness indices.

Field studies in 1978 and 1979 evaluated the effectiveness of single and combination herbicide treatments in processing peas (Pisum sativum L.) and soybeans [Glycine max (L.) Merr.] for the control of wild proso millet (Panicum miliaceum L.). Eight treatments that included dinitroaniline herbicides controlled wild proso millet adequately through the entire growing season of the early-planted peas (approximately 60 days). Wild proso millet emergence and growth in untreated peas was suppressed by the early emergence, rapid growth, and high plant density of the drill-planted crop. Trifluralin (α,α,α-trifluoro-2,6-dinitro-N,N-dipropyl-p-toluidine) at 0.8 kg/ha stunted pea growth and was the only treatment that reduced yields significantly. No herbicide treatment evaluated in soybeans controlled wild proso millet adequately for the entire growing season without reducing soybean growth and yield. Treatments containing dinitroaniline herbicides, which controlled wild proso millet in peas and resulted in good yield, did not perform similarly in soybeans.

Napropamide [2-(a-naphthoxy) N,N-diethylpropionamide] applied to cranberry (Vaccinium macrocarpon Ait.) as a granular or wettable powder formulation at 20 kg/ha in March 1978 controlled aster (Aster subspicatus Nees) and birdsfoot trefoil (Lotus corniculatus L.) without any phytotoxicity to ‘McFarlin’ cranberry vines. Earlier application in February was ineffective, and late application in April injured the vines. Napropamide 10% granular applied at 14 kg/ha in March 1979 controlled aster 90% and birdsfoot trefoil 70%, and the 50% wettable powder formulation controlled aster 90% and birdsfoot trefoil 80%. Applications of granular napropamide at 12 kg/ha in March of 1979 or 1980 controlled both weeds 70%.

In the field, soybeans [Glycine max (L.) Merr. ‘Amsoy 71′] required 4 to 6 weeks free of sunflower (Helianthus annuus L.) competition for maximum yield. Competition studies suggested that more than one type of interference was involved when sunflowers grew with soybeans. In greenhouse studies, soybean height, fresh weight, and dry weight were significantly reduced at certain sunflower and soybean densities and levels of competition. Sunflower height was not reduced by any level of competition, but sunflower fresh and dry weights were reduced with high sunflower and soybean populations. Two percent (w/w) or greater amounts of ground, mature sunflower leaves mixed into the soil reduced emergence and growth of soybeans, sorghum [Sorghum bicolor (L.) Moench ‘G-625 GBR′], and sunflower. A mixture of powdered stems and branches of sunflower also reduced growth of the three species, although it was not as phytotoxic as ground leaves. Sunflower roots apparently released exudates into the nutrient solution and soil. Sunflower root exudates inhibited sunflower emergence, and reduced sorghum, soybean, and sunflower height, fresh weight, and dry weight.

Soil-applied herbicides were evaluated for control of blackjack oak (Quercus marilandica Muenchh.), huisache [Acacia farnesiana (L.) Willd.], honey mesquite [Prosopis juliflora (Swartz) DC. var. glandulosa (Torr.) Cockerell], live oak (Quercus virginiana Mill.), Macartney rose (Rosa bracteata Wendl.), winged elm (Ulmus alata Michx.), and yaupon (Ilex vomitoria Ait.) in Texas. Various spacing of spot treatments of pelleted tebuthiuron {N-[5-(1,1-dimethylethyl)-1,3,4-thiadiazol-2-yl]-N,N′-dimethylurea} on huisache and live oak and picloram (4-amino-3,5,6-trichloropicolinic acid) on Macartney rose up to a 2.7-m square grid did not change herbicide effectiveness. Pelleted tebuthiuron at 2.2 kg/ha reduced the canopy of live oak and killed a significant percentage of plants; however, differences among herbicide formulations and distance of placement in a grid were small. On unburned plots, 2.2 kg/ha of tebuthiuron applied as pellets at 2.7-m centers and as a broadcast wettable-powder treatment killed fewer yaupon than pellets applied in most broadcast treatments. In individual-plant treatments, bromacil (5-bromo-3-sec-butyl-6-methyluracil) and picloram solutions at 2 g/plant killed 45% of the yaupon 1.5 to 2 m tall on a fine sandy loam, whereas 0.5 g/plant of either herbicide killed 70% or more of the yaupon plants 1 m tall on a loamy fine sand. Both bromacil and picloram at 1 g/plant killed all blackjack oak and winged elm sprouts 1 to 2 m tall. On a clay soil, 1 g of bromacil/plant killed 79% of the live oak and 88% of the winged elm plants, whereas picloram killed only 38 and 45%, respectively. Neither bromacil nor picloram was effective as soil treatments for killing honey mesquite.

Infestations of common milkweed (Asclepias syriaca L.), in descending order of incidence in Nebraska, occurred on areas occupied by soybean [Glycine max (L.) Merr.], oats (Avena sativa L.), sorghum [Sorghum bicolor (L.) Moench.], railroad rights-of-way, fallow land, roadsides, corn (Zea mays L.), winter wheat (Triticum aestivum L.), pasture, and alfalfa (Medicago sativa L.). Average crop yield reductions, within common milkweed communities of 11100 to 45 200 plants/ha, ranged from 2 to 10% for corn, 4 to 29% for sorghum, and 12 to 19% for soybeans. Reductions in crop yields tended to increase with increasing common milkweed populations. Germination percentage of common milkweed and sorghum were not significantly affected by growing medium conductivities below 7 and 13 mmho/cm2, respectively. Growth media at pH 2 significantly reduced germination percentage, hypocotyl length, and radicle length of both common milkweed and sorghum as compared with pH 4 to 10. Undiluted aqueous extracts of common milkweed shoot and root material significantly reduced germination percentage, hypocotyl length, and radicle length of sorghum.

Soybean [Glycine max (L.) Merr. ‘Tracy′] and two associated weeds, sicklepod (Cassia obtusifolia L.) and showy crotalaria (Crotalaria spectabilis Roth), were grown in controlled-environment chambers with day/night temperatures of 29/23 C, photosynthetic photon flux density (PPFD) of 600 μE·m−2·s-1, CO2 concentrations of 350 or 675 ppm, and one-eighth or one-half strength Hoagland's nutrient solution applied three times daily. Leaf areas and dry weights of plant parts were determined at 1, 3, and 5 weeks. Stomatal resistances, transpiration rates, leaf water potentials, and leaf chlorophyll contents were measured, and net assimilation rates (NAR) and leaf area durations (LAD) were calculated. In all species, growth in 675 ppm CO2 enhanced dry-matter production through increases in both NAR and LAD. The increased dry-matter production with one-half strength compared to one-eighth strength Hoagland's solution was, however, caused by increased LAD. Stomatal conductances and transpiration rates decreased in 675 ppm CO2, but were not affected by nutrient level. High CO2 concentration or low nutrient level generally decreased leaf chlorophyll content per unit area. Growth enhancement by high CO2 was greater in one-half strength than in one-eighth strength Hoagland's solution.

Germination of jointed goatgrass (Aegilops cylindrica Host.) seed in nitrate nitrogen (NO−3-N), gibberellic acid (GA3), or distilled water was studied in the laboratory, and depth of emergence of seedlings from soil was studied in the greenhouse and laboratory. After 14 days in germination chambers in distilled water, no difference in percent germination of 1-yr-old or freshly harvested seed existed between 10, 15, or 20 C. Jointed goatgrass seed germinated at temperatures ranging from 10 to 35 C and responded to temperature more than to NO−3-N. Seedlings did not emerge from below 5 cm in greenhouse and 6 cm in laboratory studies even though germination occurred. Jointed goatgrass has the seed germination and seedling emergence characteristics to develop into a severe annual grass weed in winter wheat (Triticum aestivum L.)-producing regions, particularly where reduced-tillage practices are utilized.

Metolachlor [2-chloro-N-(2-ethyl-6-methylphenyl)-N-(2-methoxy-1-methylethyl)acetamide] at 1 × 10−5 and 1 × 10−4 M increased the leakage of previously absorbed, 32P-labeled orthophosphate from the roots of onion (Allium cepa L.), a susceptible species, by 14 and 41 times the control values, respectively. A significant amount of 32P leaked from the roots of the moderately susceptible species, cotton (Gossypium hirsutum L. ‘DPL 61′) and cucumber (Cucumis sativus L. ‘Ashley′), whereas no significant loss of 32P occurred from two tolerant species, soybean [Glycine max (L.) Merr. ‘Bragg′] and corn (Zea mays L. ‘Pioneer 3369A′). At either 1 × 10−7 or 1 × 10−6 M, 1,8-naphthalic anhydride (NA) prevented 32P leakage from onion roots in the presence of 1 × 10−5 M metolachlor. High concentrations of NA [0.1% (w/v) suspensions], however, promoted 32P leakage and did not protect onion roots from the leakage induced by high concentrations (1 × 10−4 M) of metolachlor. Neither metolachlor nor alachlor [2-chloro-2′,6′-diethyl-N-(methoxymethyl)acetanilide], at 1 × 10−4 M, inhibited the uptake of acetate-2-14C or malonic acid-2-14C into excised cotton root tips or the incorporation of the precursors into lipids. Similarly, neither herbicide inhibited phospholipid synthesis by cotton root tips. Incorporation of 14C-choline chloride into phosphatidylcholine was not significantly inhibited by metolachlor.

To simulate the effect of MSMA (monosodium methanearsonate) drift onto rice (Oryza sativa L. 'Starbonnet’ or ‘Labelle′), foliar applications at 0.20 to 0.78 kg/ha were made on rice at stages of maturity ranging from early tillering to panicle emergence. Foliage, sampled 1 to 2 weeks after application, and grain and grain parts harvested at maturity were analyzed by arsine generation atomic absorption spectrophotometry. Washed foliage contained 0.7 to 1.5 ppm background As, and 1 to 21 ppm As after MSMA application. The As content depended on application rate, stage of maturity at application, and the formulation of MSMA. Arsenic concentrations in grain increased exponentially as the time of application approached harvest, ranging from 0.25 to 7 ppm. There was little correlation between grain residues and rates, principally because dependence on the time of application was overriding. This study confirms previous observations that there is a specific stage in rice plant development, probably meiosis, during which rice is susceptible to sterilization by arsenic, and also indicates that significant yield reduction can occur from MSMA drift even when visual injury symptoms are not obvious.

Quadratic response surface analysis was applied to data of seed germination in relation to temperature. Analysis of these data is the comparing of several levels of quantitative factors. In such situations, multiple-comparison procedures, such as Duncan's multiple range test, are inappropriate. The data were the germination percentages of four species at 55 constant or alternating day and night temperature regimes. A quadratic response surface was developed for each species using multiple-regression techniques. Estimated germination values and their confidence limits were derived from the quadratic response surface of each species for each cold-period temperature through a series of warm-period temperatures. Many parameters were synthesized from the response surfaces to evaluate germination of the four species in relation to temperature. These comparisons form a statistically valid basis from which to select the most adapted plant species and predict the best time for planting or applying weed-control treatments.

Laboratory and field studies were conducted to examine the influence of R-33865 (O, O-diethyl-O-phenol phosphorothioate) on the degradation rate of EPTC (S-ethyl dipropylthiocarbamate) in three soils that had a history of repeated EPTC application and exhibited accelerated degradation of EPTC. In field studies, addition of R-33865 to EPTC extended EPTC persistence in soil and provided increased shattercane [Sorghum bicolor (L.) Moench] control. In two soils that exhibited rapid EPTC degradation, addition of R-33865 to EPTC extended the half-life of EPTC from 9 to 18 days and from 6 to 15 days, respectively. Evolution of 14CO2 from 14C-carbonyl EPTC-treated soils with a prior history of EPTC treatment was significantly reduced when R-33865 was added; however, the initial lag period of EPTC degradation was not restored. Addition of R-33865 to EPTC on soils with no prior EPTC treatment did not extend persistence of EPTC in soil.

“We're Number 1” has become an oft-repeated claim in sports, but agricultural research in the United States must admit to being only a poor Number 2 (9). The Soviet Union exceeds the United States 3.4 to 2.2 in percent of gross national product invested in agricultural research, 60000 to 12000 in numbers of agricultural scientists, and 150000 to 13000 in support personnel (9). Furthermore, agricultural scientists hold eminent positions in the Soviet Union and are regularly admitted to the Soviet Academy of Science, whereas few United States agriculturists are elected to the United States National Academy of Sciences. This disparity is hard to understand in view of the importance of agriculture in the United States. For example, it is anticipated that in 1982 the United States will pay $60 billion for imported oil and that two-thirds of this will be paid for by agricultural exports (6). According to Schultz (8) in his address on socio-economic aspects of agriculture, “the future food supply is dependent in large measure on achievements in agricultural research”. It would appear that accepting second place to the Soviet Union in agricultural research is even more unacceptable than second place in space. This audience does not need to be convinced of the importance of agricultural research. We might, however, profit by enumerating some of the characteristics of a high quality research program. The comments I am going to make are not intended to be all inclusive and are primarily based on my observations of agricultural research in land-grant universities. Most of the comments are, however, equally applicable to other fields of research and to other agencies.

We are meeting near the Boston Common, an historic 50-acre public park that was set aside in 1630 for “common use as a cow pasture and training field.” Records show that 100 people (pirates, Indians, Quakers, and suspected witches) were hanged on the Common by the early Puritans who established the Massachusetts colony.

There were no farmers or scientists on this list. Hopefully, after this presentation, my name will not be added to the Puritans' “hit” list.