Alfalfa is a key economic crop in all 11 Western states. In this paper we examine historical factors and key recent ‘megatrends’ which will likely impact alfalfa in the future. Acreage, yield, and production has mostly been static over the past 20 years, but the importance of alfalfa and other forages is thought to be increasing, given high world demand and increases in Western dairy herds. Key trends include a rise in emphasis on forage quality and testing, the advent of genetically engineered alfalfa, emerging pests such as aphid infestations and stem nematode. The economic and environmental health of the Western dairy sector is certainly of concern. Water restrictions, cost of production, availability, and quality are undoubtedly the most important limiting factor for alfalfa for the future, as well as a need to increase yields and improve consistency of forage quality testing. Researchable issues include development of salt resistance and drought tolerance, irrigation management approaches, improved IPM techniques, and forage quality evaluation. The lack of grower and USDA support for research is noted as a key limiting factor for the future of forage crops.

Plant description: Grain sorghum (milo) is a warm season, annual grain crop. It is more resistant to salt, drought, and heat stress than most other crops. Nevertheless, highest yields are obtained when stresses are minimized. Hybrids: Grain sorghum hybrids can be classified as short, medium or full season. Medium and medium-full season hybrids are grown in Arizona as a general rule. Short season hybrids do not have the yield potential to be profitable under our growing conditions. Sorghum hybrids grown for grain are usually short in stature (not over 4 ft tall), but dual purpose hybrids utilized for both forage and grain can be much taller (5 ft or taller). Grain color can be purple, red, brown, bronze, tan, yellow, creamy or white. Bird damage to the heads may be reduced in hybrids with high tannin content in the grain. Planting date: Suggested planting dates for grain sorghum are presented in Table 1. Sorghum seed will germinate when the soil temperature at seeding depth is 50°F, but germination and growth will be slow and the seedlings will be susceptible to disease. Faster germination and superior establishment is obtained when the soil temperature is 60°F at 8 am for more than 5 consecutive days. Sorghum may be planted in the summer but grain yields are usually less than a spring planting. The optimum date to plant in the summer is late enough to avoid the heat during bloom but early enough to avoid frost and poor drying conditions in the fall.

An integrated approach to weed management in wheat and barley includes preventing the introduction or spread of weeds, crop rotation, cultural practices that result in a vigorous crop, and chemical treatment when necessary. Weed seed can be spread from weeds growing along ditch banks and other areas, by tillage and harvesting equipment, and through contaminated crop seed. Crop rotation is an integral component of weed management since many weeds are easier to control in certain crops. Pre-irrigating can germinate weed seeds which can be eliminated by tillage at planting time. Planting below dry soil in a mulch can inhibit germination of certain shallow-germinating weeds such as canarygrass, but not other weeds such as wild oats that can emerge from 3 inches or more. Early planting dates generally result in plants that tiller more and are more competitive with weeds. Drill seeding produces a more uniform stand than broadcasting and helps in weed control. High seeding rates are also more competitive with weeds. Land leveling is important for weed control since weeds often flourish in low areas. Providing adequate but not excessive water and fertilizer maintains a vigorously growing crop that is competitive with weeds. Chemical treatments are important tools in weed management to maintain yield and quality and prevent proliferation of weeds that could affect future crops.

About 40% of the alfalfa hay in the United States is produced in the 11 western US states of Arizona, California, Colorado, Idaho, Montana, Nevada, New Mexico, Oregon, Utah, Washington, and Wyoming. This region also supplies the vast majority of the seed for the nation’s alfalfa plantings, and it contributes significantly to exports of alfalfa hay and seed. Western states played a crucial historical role during the development of alfalfa in the United States, as alfalfa moved from West to East in the latter half of the 19 Century. A present-day survey of western states showed a wide variety of production practices in these states, ranging from 2 to 10 cuts/year, from very dormant to very nondormant varieties grown on soils from heavy clays to beach sands. Respondents reported water and irrigation management as key limiting factors. All but one state reported that the importance of alfalfa was increasing in their state. Alfalfa is likely to remain a key crop or increase in importance in these states due to the ascendancy of the dairy industry in the West.

Various forms of microtopography are widely distributed and exist in the loess area of northern Shaanxi. Microtopography is also an important consideration for near-natural vegetation restoration models. The soil quality under the different microtopography types affects which near-natural vegetation configuration and restoration mode should be applied. Therefore, this paper took the microtopography of the Hegou watershed, which was restored by the natural exclosure method, and that of the Chaigou watershed, which was restored by artificial afforestation, in the loess region of northern Shaanxi as the research objects. A comprehensive evaluation of the soil quality in the study area was carried out by assessing 22 soil indicators and performing sensitivity analysis and principal component analysis. The results showed the following: (1) Soil available phosphorus, total nitrogen, organic matter, sucrase activity, urease activity, maximum water-holding capacity, field capacity, capillary water-holding capacity, noncapillary porosity, natural water content, available nitrogen, available potassium, cation exchange capacity, total phosphorus, total potassium, alkaline phosphatase and catalase constituted a sensitive-indicator data set for soil quality evaluation in the study area. (2) There was a significant linear fit between the sensitive-indicator data set and the all-indicator data set (y = 1.032x − 0.027, R2 = 0.96 (P < 0.05)). (3) The microtopography types under natural restoration were ranked by soil quality as follows: collapse (0.672) > platform (0.565) > shallow gully (0.529) > gully (0.515) > undisturbed slope (0.422) > scarp (0.351). The microtopography types under artificial afforestation were ranked by soil quality as follows: gully (0.731) > platform (0.66) > undisturbed slope (0.431) > shallow gully (0.411) > scarp (0.395) > collapse (0.221).

Phosphorus plays a key role in the growth and development of alfalfa and is normally the only nutrient application that is recommended. Deficiency symptoms are not always definite and normally occur only during the cool periods of the year. Stunting is the most common symptom and will vary with the degree of deficiency and the soil conditions. Leaves sometimes appear dark and bluish -green in color. A survey was conducted in Yuma County in 1991 to evaluate the soil phosphorus levels in a cross -section of established alfalfa fields. The levels of extractable phosphorus (P) in the 30 fields sampled varied from 3 to 43 parts per million. 50% of these fields were in what is considered the high range of above 15 ppm. 17% of the fields were in the medium range containing 11 to 15 ppm. 10% of the fields were in the low range containing 6 to 10 ppm and 20% of the sampled fields were in the very low range containing below 6 ppm. A test was conducted to evaluate the effect of phosphorus on alfalfa yield for the first two years of production on a soil containing lowmedium levels of phosphorus of 11 ppm extractable P.

A test was conducted to evaluare the effect of irrigation termination during the summer (July through October) and winter (October through February) upon alfalfa yield and stand Termination during the summer harmed the stand and seriously reduced yields. Termination during the winter resulted in minor yield reduction and no stand damage. The benefits of suboptimal irrigation are site specific and dependent upon many factors. This test demonstrated that the winter should not be overlooked as a time to conserve water on alfalfa production.

INTRODUCTION Sewage sludge disposal is a problem for most metropolitan areas. Methods of sewage sludge disposal include dumping into oceans, rivers, or landfills or application onto agricultural lands. Application of sewage sludge onto agricultural land is a preferred method of disposal. Sewage sludge is valued in crop production as a source of plant nutrients, particularly nitrogen and phosphorus, and as a source of organic material. Liquid sludge from Tucson is currently being applied on agricultural land near Marana. Previous work has demonstrated the value of Tucson sewage sludge as a source of plant nutrients for small grains and cotton (Unger and Fuller, 1985; Watson et al., 1985; Day et al., 1988; Ottman et al., 1989). However, the influence of Tucson sewage sludge on soil properties, nitrogen availability, and yield has not been reported in detail. The present study comprises the fourth year in a 5 -year study designed to determine the long-term effects of Tucson sewage sludge in crop production.

Westbred 881 durum wheat commands a premium price due to its superior quality, but produces a lower yield than other commonly grown commercial cultivars. This study was initiated to improve our understanding of how best to manage Westbred 881. Two durum wheat cultivars (Westbred 881 and Aldura) were planted at 5 seeding rates (30, 60, 120, 180, and 240 lbs. seed/A), 5 row spacings (3, 6, 12, 18, and 24 inches), and two planting dates (Dec. 1 and Jan. 16) at the Maricopa Agricultural Center. Both cultivars produced optimum yields at seeding rates of 120 to 180 lbs/A for the Dec. 1 planting date. At the Jan. 16 planting date, however, yields of Westbred 881 increased linearly with seeding rate up to 240 lbs1A, while Aldura produced optimum yields between 120 and 180 lbs. seed/A. At the Dec. 1 planting date, Aldura produced similar yields at row spacings from 3 to 12 inches, while the yield of Westbred 881 decreased linearly with an increase in row spacing. The highest yield achieved in this study was with Westbred 881 at the 3 -inch row spacing. Row spacings of 6 to 12 inches were optimum for both Westbred 881 and Aldura at the Jan. 16 planting date. The seeding rate and row spacing responses attained with Westbred 881 may be related to its tittering characteristics. INTRODUCTION Westbred 881 durum wheat receives a premium price due to its superior quality. However, grain yields of Westbred 881 have been 5% to 20% lower than Aldura, a commonly grown commercial cultivar, in yield tests conducted by the University of Arizona. The present recommendation is for producers to use their better land and good management practices when growing Westbred 881. The objective of this study was to determine optimum seeding rates and row spacings for Westbred 881 compared to Aldura. MATERIALS AND METHODS Field studies were initiated at the Maricopa Agricultural Center in the 1986-87 growing season on a Trix clay loam. The previous crop was Sudan grass. Two durum wheat cultivars (Westbred 881 and Aldura) were planted at 5 seeding rates (30, 60, 120, 180, and 240 lbs. seed/A) at 5 row spacings (3, 6, 12, 18, and 24 inches) and at two planting dates (Dec. 1 and Jan. 16). The experimental design was a 5x5 Latin square with seeding rates or row spacings as main plots and cultivars as sub -plots. The seeding rate trial was planted in 6 -inch rows and the row spacing trial was planted at l00 lbs. seed /A.

This study is part of an ongoing effort on evaluate alfalfa cultivar performance at various locations in Arizona. Forage yields of 25 alfalfa cultivars and experimentals were measured at the Maricopa and Yuma -Mesa Agricultural Centers. During the time period reported, many of the newer cultivars were more productive than the popular cultivar CUF 101 . Selection of alfalfa cultivars should be based upon fall dormancy, pest resistance, seed cost, and yield potential. MATERIALS AND METHODS Entries for these 4 trials were solicited from originators in 1986, with a maximum of three entries per source. Promising experimentals were requested in addition to commercial cultivars so that yield information would be available for those experimentals that eventually become commercially available. From this initial request, 25 cultivars and experimentals were chosen for evaluation at the Maricopa and Yuma -Mesa Agricultural Centers. Only 4 of the 25 entries differed between locations. A partially balanced 5 x 5 lattice with 4 replications was used at each site. Seed was planted in 6 inch rows in plots 3 feet wide and 17 feet long on a Casa Grande sandy loam on October 3, 1985 at Maricopa and on a Superstition Sand on September 24, 1985 at Yuma -Mesa. The plots were surrounded by the alfalfa cultivar 'Lew' at Maricopa and 'CUF 101' at Yuma -Mesa. Approximately 250 lbs P205 /A was applied preplant. The plots were handharvested and fresh weights recorded. Thus, the plots were not subjected to wheel traffic from harvest equipment, as occurs in commercial alfalfa production. At the Yuma -Mesa, yields were obtained from only four selected cuts per year (2 spring, 1 summer, 1 fall). This is highly correlated with the total yield obtained from all cuttings based on studies conducted in the Imperial Valley by the University of California. The plots were generally cut at an early to mid -bloom stage of growth. The plots were subjected to the normal pressure from the Egyptian alfalfa weevil, aphids, thrips, leaf hoppers, alfalfa caterpillar, and beet armyworm; these pests were controlled as needed. Downy mildew, Stemphylium, and common leaf spot were observed but probably did not limit yield. The seedling alfalfa at the Yuma -Mesa was sprayed at the 2 -3 trifoliate stage with 2, 4 -DB amine to control various broadleaf weeds. During the peak consumptive -use periods of the late spring and summer, irrigation water was applied 2 to 3 times per cutting at

RCB with 3 (wheat) or 4 (barley) replications 12/20 & 12/21, 1985 06/09 & 06/10,1986 Wheat 90 lbs. /acre Barley 90 lbs. /acre 12/22/85 5.4 acre /in. 02/08/86 6.0 acre /in. 03/05/86 6.0 acre /in. 03/22/86 3.6 acre /in. 04/09/86 3.24 acre /in. 04/22/86 2.52 acre /in. TOTAL: 26.76 acre /in. 12/18/85 132 lbs. N per acre as NI-13 03/05/86 29 lbs. N per acre as NH3 Cotton None Thimet 20 03/07/86 5 lbs. per acre Wheat 25 x 860 Barley 25 x 800 Wheat Indio Silt Loam, Ripley Silt Loam Barley Meloland Sandy Loam, Holtsville Silt Clay, Indio Silt Loam, Ripley Silt Loam

Crop ScienceVolume 26, Issue 2 cropsci1986.0011183X002600020044x p. 387-387 Registration of Germplasms Registration of Arizona 8501 Barley Germplasm for Disturbed Land Reclamation A. D. Day, A. D. Day Professor Dep. of Plant Sciences, College of Agriculture, Univ. of Arizona, Tucson, AZ, 85721Search for more papers by this authorK. L. Ludeke, K. L. Ludeke agronomist Ludeke Corp., 3550 North Central Ave., Phoenix, AZ, 85012Search for more papers by this authorM. J. Ottman, M. J. Ottman extension specialist Dep. of Plant Sciences, College of Agriculture, Univ. of Arizona, Tucson, AZ, 85721Search for more papers by this author A. D. Day, A. D. Day Professor Dep. of Plant Sciences, College of Agriculture, Univ. of Arizona, Tucson, AZ, 85721Search for more papers by this authorK. L. Ludeke, K. L. Ludeke agronomist Ludeke Corp., 3550 North Central Ave., Phoenix, AZ, 85012Search for more papers by this authorM. J. Ottman, M. J. Ottman extension specialist Dep. of Plant Sciences, College of Agriculture, Univ. of Arizona, Tucson, AZ, 85721Search for more papers by this author First published: 01 March 1986 https://doi.org/10.2135/cropsci1986.0011183X002600020044xCitations: 3AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article.Citing Literature Volume26, Issue2March–April 1986Pages 387-387 RelatedInformation

Information is incomplete on the general growth and production of spring barley grown as a winter -annual as opposed to an annual plant. Experiments were conducted over a five -year period at the Yuma Valley Agricultural Center, Yuma, Arizona, to study the effects of growth cycle, nitrogen fertilizer, planting rate, and genotype on the length of time from planting to flowering, plant height, percent lodging, and hay yield of spring barley (Hordeum vulgare L.) in a semiarid environment. Spring barley produces more forage when grown as a winterannual than when grown as an annual. When barley is grown for forage it should receive more nitrogen fertilizer and be planted at a higher seeding rate than when it is grown for grain production. Barley genotypes differ in their forage potential and should be carefully selected for adaptation to the specific environment when high hay production is the principal objective.