| Title |
Investigators | Department | Objectives | Approach Keywords | Progress Reports | Impact Statements | Publications | |
Project * COL00615 | |
| Title | Enhancing Field Crop Production in the Arkansas River Valley |
| Investigator(s) | Berrada, A; |
| Department | Soil and Crop Sciences |
| Objectives | (1) Evaluate crops for their yield potential and adaptability to the Arkansas River Valley and develop best management practices (BMPs) for priority crops. (2) Determine the effects of water stress/irrigation deficit on field crops and develop strategies to manage limited water supplies. (3) Evaluate salinity and its effects on field crops in the Arkansas River Valley and devise BMPs to mitigate potentially negative impacts of elevated salt concentrations in our soils and waters. (4) Develop BMPs to enhance nutrient use efficiency and minimize the risk to the environment from over application, runoff, or leaching of nutrients and known pollutants. |
| Approach | Objective 1: Evaluate crops for their yield potential and adaptability to the Arkansas River Valley (Valley) and develop best management practices (BMPs) for priority crops. Currently, the focus is on alfalfa, corn, sorghum, winter wheat, and dry bean. Other crops may be tested in the future as the need arises. Occasionally, multi-year results will be analyzed to assess progress and make adjustments to the program. Other trials will be conducted to assess potential of- and develop management practices for new and existing crops. Objective 2: Determine the effects of water stress/irrigation deficit on field crops and develop strategies to manage limited water supplies. One study will compare furrow and drip irrigation under full and limited irrigation regimes and examine their effects on water use efficiency, crop yield, and soil salinity. Corn will be grown in 2005 and 2006, and soybean or dry bean in 2007. Measurements will include precipitation, runoff, soil water content, crop yield, and salt concentration. Objective 3: Evaluate salinity and its effects on field crops in the Arkansas River Valley and devise BMPs to mitigate potentially negative impacts of elevated salt concentrations in our soils and waters. This will be achieved in conjunction with objectives 1 and 2. Test crops include dry bean, corn, and onions. Salt concentration in the bed and furrow will be measured at planting and harvest in the top three feet of soil and its effects on crop growth and yield will be assessed. The results from this and other studies will be used to make recommendations on how to alleviate potentially harmful effects of salinity on crop production in the Valley. Objective 4: Develop BMPs to enhance nutrient use efficiency and minimize the risk to the environment from over application, runoff, or leaching of nutrients and known pollutants. Two field experiments will be initiated in 2005 to determine the effects of N and P rates on crop (corn and alfalfa) yield and quality, plant N and P uptake, and soil N and P test levels. Additional monitoring may be done on farmers fields. Both synthetic fertilizers and cattle manure will be used in these experiments. The alfalfa experiment will be established on a soil with high nitrate-nitrogen level to asses its ability to mine the excess nitrate. The potential impact of manure application on soil salinity will be examined as well. |
| Keywords | Arkansas River Valley, Crop testing, Salinity, Deficit irrigation, Drip irrigation, Water management, Nutrient management, Manure management, Best management practices, Pollutants, Weighing lysimeter |
| Progress Reports | |
| 1993 | Dry bean breeding activitiesincluded production and evaluation of 13 F2's, 81 F3's, and 40 advanced lines. All advanced lines were evaluated for reaction to common blight, tolerance to drought stress, and yield potential. The pinto bean line CZ-59196 was evaluated pending its release in 1994. Advanced generation breeding materials from CIAT were evaluated based on seed type, adaptation, and yield potential. A CIAT high altitude adaptation nursery was also grown. Variety yield trials were conducted on irrigated and dryland pinto beans, irrigated spring wheat, irrigated spring barley, irrigated oats,and dryland hard red winter wheat. Three lines of spring wheat UT613960, UT002464 and ID000367 have been identified for possible release in 1994 after four years of testing. Alternative crops were evaluated for adaptation to southwestern Colorado - rapeseed, safflower, crambe, and corn. Irrigation research continued to refine irrigation scheduling techniques for dry beans and spring wheat. A project to evaluate the feasibility of commercial orchards (apple, cherry, peach) in southwestern Colorado was continued for a second year. No-till, minimum and conventional tillage systems for dryland dry bean and winter wheat rotations were evaluated for the fifth year. A summary of the 1989-1993 results has been completed. A study to determine optimum winter wheat planting dates and efficacy of fall applied insecticides as they relate to overwintering of the Russian wheat aphid was continued. |
| 1994 | Two hundred ninety F3's, 86 F4's, and 115 advanced lines of dry beans were evaluated under dryland conditions and a smaller number under irrigation. Advanced generation breeding materials from CIAT also were evaluated. The dry bean variety Fisher and the spring wheat variety Sylvan were officially released in 1994. Two new varieties of garbanzo beans were evaluated for yield potential and adaptation to southwestern CO. Irrigation research focused on scheduling techniques for dry beans and spring wheat. A new project was initiated to determine the optimum N level for dry bean production under various irrigation regimes. An economic evaluation of reduced tillage systems in southwestern CO was conducted. Several changes were made in the conservation tillage project based on the 1989-1993 results. A study on the efficacy of seed applied insecticides to control Russian wheat aphid and dwarf bunt was initiated in the fall. Fruit tree management investigations were continued for the third year. Eight varieties of grapes were planted to evaluate their potential in southwestern CO. A highly successful field day was held at the Center. Irrigation management, alternative crops, reduced tillage and integrated pest management were featured. The 150 people in attendance was a record number. |
| 1995 | The dry bean breeding program included the evaluation of over 2000 lines under dryland and irrigated conditions. Advanced generation breeding materials from CSU, CIAT and other sources were evaluated based on seed type, adaptation, and yield potential. The feasibility of garbanzo bean production was evaluated for the second year in Yellow Jacket, CO. Eight experimental lines from ICRISAT and four varieties from California and Washington were tested for their adaptation, disease resistance, and yield potential. They averaged 1,100 kg/ha, well above the average (577 kg/ha) of the dryland pinto bean variety trial. Other alternative crops evaluated in 1995 were edemame beans (edible soybeans) and peppermint. More testing is needed to assess the potential benefits of these two crops in southwestern Colorado. Dryland winter wheat yields were exceptionally high in 1995 due to favorable moisture conditions. The yield averaged over four trials was 2,654 kg/ha, about twice the long-term average for southwestern Colorado. The importance of timely wheat planting was again demonstrated in 1995. Winter wheat planted no later than September 29 outyielded October-planted wheat by an average of 995 kg/ha . A combination of early planting and timely weed control led to non significant differences in grain yield among no-till and minimum-till wheat after fallow, and conventional-till wheat after dry bean. Moreover, wheat yields were not affected by the partial substitution of a cover crop (black lentils) to fallow. |
| 1996 | The 1995-96 season was one of the driest on record in southwestern Colorado. A total of 22 cm of precipitation was recorded at Yellow Jacket, CO from October 1995 through September 1996, compared to a 30-year average of 40 cm. Consequently, dryland winter wheat and dry bean yields were extremely low averaging less than 1000 kg/ha and 200 kg/ha, respectively. Russian wheat aphid (RWA) infestation was very high, causing substantial yield reductions in untreated wheat . The seed treatment Gaucho 480 FS (imidacloprid) at 250 mg a.i./100 kg was effective in controlling RWA in irrigated spring wheat. The treated plots averaged 1.2 RWA per infested tiller while the untreated plots averaged 6.1 RWA per infested tiller. Grain yield was 6,345 kg/ha in the treated plots and 4,807 kg/ha in the untreated ones. Gaucho was also effective in controlling RWA in 'Fairview' hard red winter wheat under dryland conditions but not under irrigation. Several advanced lines from the dry bean breeding program at Fort Collins, CO were tested at Yellow Jacket, to identify pinto bean varieties with high yield potential and disease resistance. The yields were somewhat disappointing since they only averaged 1651 kg/ha but a few lines exhibited desirable characteristics which will be investigated further. Much higher pinto bean (var. 'Bill Z') yields, 3,255 kg/ha on the average, were obtained in the irrigation by N rate experiment. There were no significant differences among N rates (0 to 112 kg N/ha in 28 kg/ha increments). |
| 1997 | The conversion of dryland farms to irrigation in the Dolores Project area is fairly recent (1987-Present). In 1987, only 1,169 acres were irrigated in the full service area (FSA) and in 1996, approximately 86% of the allocated acres (28,000) was in production. The amount of water used per irrigated acre exceeded the allocated amount in 6 out of 10 years. The anticipated system capacity of 20.5 inches per acre was based on a water delivery efficiency of 87% and an 'ideal' crop rotation of 55% alfalfa, 20% small grains, 15% dry bean, 3% pasture, and 7% corn. While water delivery efficiency has been exceeded, the acreage in alfalfa has been much higher than anticipated (70 to 80%) which may explain in part the high water usage during dry years. Poor management is also to blame. A questionnaire was sent to 178 farmers -of which 95 were farm operators, in the fall of 1996 to assess irrigation management in the Full Service Area (FSA) of the Dolores Water Project. Forty-two completed questionnaires were returned. In addition, 13 fields were monitored during the 1997 irrigation season to gain a better understanding of the issues identified in the survey. The majority (88%) of the respondents used siderolls to irrigate their land while 44% used siderolls and/or center pivots. Forty-two per cent of the respondents reported using 6 gpm or smaller nozzles on some of their systems while 22% reported using 9 gpm or larger nozzles. The smaller nozzles approximate the Dolores Project pumping capacity (5.8 gpm during peak usage) while larger nozzles may result in deep percolation or runoff if not carefully monitored. Sixty-two percent of the respondents reported irrigation water runoff from their fields while 36% reported no runoff. Fifty-two per cent of the respondents based their decision on when to irrigate by checking soil moisture with a shovel or soil probe. However, 45% reported that they continuously moved their siderolls regardless of soil moisture content and/or crop water use. Most of the respondents expressed the need for timely information on crop water use and irrigation scheduling. Earlier studies at the southwestern Colorado Research Center revealed the need to develop crop coefficients that more closely reflect the climatic conditions in southwestern Colorado than those used in existing irrigation scheduling programs. It is important that local environment be considered in any adaptation or transfer of water management programs. Several tools for improving irrigation management in the Dolores Project Area were demonstrated during the well-attended August '97 field day at the research center. More research and outreach activities are scheduled for 1998 to help irrigators in the Dolores Project area manage their water allocation efficiently. |
| 1998 | Southwestern Colorado is traditionally a dryland dry bean production area but the combination of low yields and declining prices has led to a substantial reduction in dry bean acreage in the last four years. There is a need to diversify dryland cropping systems in southwestern Colorado to minimize risks. Field studies have been conducted at the Southwestern Colorado Research Center since 1994 to evaluate chickpea (Cicer arietinum L.) as an alternative to dry bean. The results show good yield potential and adaptability of several cultivars. Average chickpea yields of 1000 to 1700 kg/ha were achieved under dryland conditions at Yellow Jacket, CO in 1995, 1997, and 1998. In comparison, Montezuma county dry bean yield ranged from a low of 325 kg/ha in 1995 to a high of 784 kg/ha in 1997. Cultivar and planting date had a significant effect on chickpea seed size and yield in 1997 and 1998. 'UC27' had the highest seed yield in both years followed by 'Dwelley' in 1997. Acceptable seed quality for canning was produced by 'UC27' and 'Dwelley' and for dry packaging by 'Sanford' and 'Evans'. Optimum planting date appears to be around 21 May at Yellow Jacket. Irrigation water and/or N fertilization increased chickpea seed yield significantly in 1994-1996. 'Sanford' seed yields of 2500 to 2700 kg/ha were produced with 56 kg N/ha and approximately 28 cm of precipitation (irrigation plus rainfall). Chickpea and dry bean can be grown and processed using similar equipment and management practices. Chickpea is more frost tolerant than dry bean and can be planted and harvested few weeks earlier, allowing for a more optimum planting date of winter wheat. Southwestern Colorado is well suited to dry packers and canners. The freight availability may create some problems in timely deliveries and transportation expenses. Good chickpea seed quality has been produced in southwestern Colorado but late planting and/or frequent rains can delay maturity and increase the incidence of stained seeds. More research is needed to identify cultivars and management practices that will enhance the marketability of chickpea produced in southwestern Colorado. |
| 1999 | Over 80% of the irrigated acreage in Dolores and Montezuma Counties are in alfalfa. There is a wide variation in the amount of phosphorus (P) and potassium (K) recommended for optimum alfalfa hay production. Most soils in southwestern Colorado test in the low (0-3 ppm) to medium range (4-7 ppm) for P and in the high range for K (>120 ppm) based on AB-DTPA test. A field experiment was initiated in 1995 at the Southwestern Colorado Research Center to determine the response of irrigated alfalfa to P and K rates and assess P and K maintenance rates. Four rates of P (0, 37, 74, and 148 kg/ha) and three rates of K (0, 93, and 186 kg/ha) were applied in the fall of 1995 as factorial treatments in a randomized complete block design with four replications. An additional 37 kg/ha of P was applied to half of each plot in the spring of 1997,1998, and 1999. Initial soil test results were pH - 7.7, O.M. - 1.0%, AB-DTPA P - 5.2 ppm (0-30cm), and K - 150 ppm (0-30cm). The Colorado State University 3-year recommendation would have been 74 kg/ha of P and no K fertilizer. Each plot was harvested twice in 1996 and 1999, and three times in 1997 and 1998. Alfalfa dry matter (DM) was determined for each cutting and each plot in all years, and in 1997 through 1999, alfalfa P and K concentration was also measured. Soil P and K concentration was measured in 1998 and 1999 from selected treatments. Data from this study show that: alfalfa DM increased significantly in 1996 with 93 kg/ha of K. There was no significant response in subsequent years although higher K concentration was observed in 1997 with 186 kg/ha of K compared to the untreated check. Alfalfa DM did not respond to an initial application of up to 148 kg/ha of P except in 1999. Alfalfa P concentration was, however, significantly impacted by P fertilizer rate in 1997 and 1998. The addition of 37 kg/ha of P in the spring of 1997 through 1999 maintained soil P level in the medium range for fertilizer recommendation. It also significantly increased alfalfa P concentration in 1997 and DM in 1998 and 1999 in the initial zero and low P fertilizer treatments. The P x K interaction on alfalfa P concentration or DM was not significant at alpha=0.05. |
| 2000 | This was the first year of a three-year western SARE project titled `Developing Sustainable Dryland Cropping Systems in SW Colorado and SE Utah Using Conservation Tillage and Crop Diversification'. The main purpose of this project is to evaluate cropping systems that would maximize water (from rain and snow) use efficiency and economic return and minimize the detrimental effects to the environment, i.e., due to soil erosion. Three field trials were established in the fall of 1999 and spring of 2000 at the Southwestern Colorado Research Center and Goodman Point in Montezuma County, CO and near Eastland in San Juan County, UT. Treatments vary among sites but include at least one cropping system that is common to the area. A severe drought during most of the 1999-00 season (October-September) resulted in partial or total crop failure. Total precipitation from October 1999 through September 2000 at the Research Center averaged 213 mm compared to a 30-year average of 404 mm. Only winter wheat after summer fallow produced near average seed yield. A spring application of 44.8 kg ha-1 of N at the Eastland site caused a significant increase in wheat yield (1940 vs. 1565 kg ha-1 for the control). Wheat protein content was not affected by N application. At the Research Center, winter wheat yield was significantly higher after summer fallow than after spring crops. The lowest yield was obtained after chickpea, probably due to extensive soil moisture extraction by chickpea as compared to pinto bean, which has a shallower root system. The combination of severe drought and low soil moisture content at planting contributed to extremely low pinto bean and chickpea yield at Goodman Point. The plot area had been in alfalfa for seven years until late summer 1999 when alfalfa was killed using a Noble blade implement. We hypothesize that alfalfa, because of its taproot system, used most of the available soil moisture prior to its termination in 1999. The fall of 1999 was extremely dry, as were the months of December, February, and April, allowing for very little recharge of the root zone prior to the planting of pinto beans and chickpeas on May 18, 2000. Additional stress may have resulted from too much residual N, which could have favored vegetative growth at the expense of seed production. |
| 2001 | The conversion of dryland farms to irrigated in the Dolores Project area is fairly recent (1987-present) and there are plans to irrigate additional land in the future. Thus the importance of generating information to assist farmers to manage their water allotment efficiently. The amount of water used per irrigated acre exceeded the allocated amount in 6 out of 10 years in the Full Service Area (FSA). The anticipated system capacity of 0.211 ha m was based on a water delivery efficiency of 87% and an 'ideal' crop rotation of 55% alfalfa, 20% small grains, 15% dry bean, 3% pasture, and 7% corn. Water delivery efficiency has been exceeded (95% versus 87%), in effect raising water allotment to 0.232 ha m. The land in irrigated alfalfa has been much higher than anticipated (90% in 2000) which may explain in part the high water usage during dry years. A study was initiated in 1996 and completed in 2001 to (1) assess irrigation water management in the FSA, (2) demonstrate the use of the Watermark moisture sensor and ETgage atmometer for irrigation scheduling purposes, and (3) initiate research and education programs to address specific constraints. A survey conducted in the fall of 1996 identified concerns relating to irrigation system design at the farm level , runoff, and irrigation scheduling. Watermark sensors were used to monitor soil moisture in 25 irrigated fields in 1997 through 1999. ETgage atmometers were used to monitor crop evapotranspiration (ET) at five locations. Irrigation and rainfall amounts were measured with rain gauges. ET based water balance tables were constructed for each alfalfa field and year. Generally, the water balance was positive to near zero at the first alfalfa cutting and negative at the second and third cuttings. There was good to partial agreement between the Watermark sensor readings and water balance computations in 11 out of 17 alfalfa field by year sites. Where there were large discrepancies between the two methods, Watermark sensor readings appeared to better reflect water availability to the crop than did water balance computations. Water supply in most fields was not enough to keep up with crop ET and maintain adequate soil moisture. A strong correlation was found between the Watermark sensor Model 200SS readings and water content of the predominant soil type in the FSA. A third degree polynomial provided an excellent fit for the data. Slow Watermark response to soil drying was observed at readings of approximately 0 to 10 kPa and above 150 kPa. Close agreement between alfalfa reference evapotranspiration (ETr) values measured with ETgage Model A or computed using the 1982 Kimberly-Penman equation was achieved during the growing season (May to September). The highest correlation was obtained when ETr values were averaged over three and seven-day periods. |
| 2002 | A major challenge for crop production in southwestern Colorado and southeastern Utah is water availability. This was abundantly clear in 2002 due to a severe drought, following two years of below average precipitation. Total precipitation at Yellow Jacket, CO in 2002 was 217 mm, or 54 % of normal. It was even less (39 % of normal) during the crop season (Oct. 2001 to Sep. 2002). The cumulative effect of the 3-yr. drought severely impacted crop production in southwestern Colorado and southeastern Utah. In a dryland cropping systems research study, winter wheat averaged 838 kg/ha at Yellow Jacket, CO; 575 kg/ ha at Eastland, UT; and less than 200 kg/ha at Goodman Point, CO. Winter wheat after a 13-month fallow season produced significantly more grain at two locations than winter wheat after spring grains (oat, safflower, chickpea, pinto bean, or corn). This was due to more available soil moisture and earlier seeding after fallow than after spring grains. There was also a significant advantage of minimum tillage over conventional tillage in the wheat-fallow rotation at one location in 2002. The 2000 to 2002 results indicate that growing one crop each year in the semi-arid environment of southwestern Colorado and southeastern Utah may not be feasible in the long term. Two-to four-year crop rotations with one fallow year would be more sustainable. Irrigated crop production was also severely impacted by limited water supplies in 2002. Full service irrigators in the Dolores project were allotted 28% of their normal water allocation of 1,411 mm/ha. This was barely enough to produce one cutting of alfalfa hay. Alfalfa dry matter production was strongly correlated to irrigation depth at Yellow Jacket in 2002. It took 137 mm of water (precipitation + storage) on average to produce 2.2 Mg/ha of alfalfa hay, using subsurface drip irrigation. Substantially more water would have been required to produce the same amount of hay if a sprinkler irrigation system had been used in 2002. |
| 2003 | The recent drought and expanding alfalfa acreage in southwestern Colorado under the Dolores Irrigation Project resulted in high water usage in 2000 and 2001 and water shortages in 2002 and 2003. Only about 28% of the normal water allotment (1430 mm ha-1) in 2002 and 60% in 2003 was delivered to Full Service (FS) irrigators. This raised concerns about the long-term feasibility of the Dolores Project and emphasized the need for research and education to enhance water conservation and management in southwestern Colorado. In this context, a field experiment was conducted in 2002 and 2003 to investigate the effect of water stress on alfalfa dry matter (DM) yield and hay quality. Three irrigation treatments (full irrigation and moderate and severe water stress) were imposed on three alfalfa cultivars with contrasting dormancy rating in a split-block design. The irrigation system used was subsurface drip irrigation (SDI) with 152.4 cm lateral spacing and 41 to 46 cm placement depth. Total alfalfa DM production (adjusted to 12% moisture) averaged 9.5 tons per hectare in 2003, with no significant differences among cultivars. Irrigation treatment had a pronounced effect on alfalfa DM production, regardless of the cultivar. The non-stressed treatment produced the highest DM yield (11.6 t/ha), while the moderately and severely stressed treatments produced 10.0 and 6.8 t/ ha, respectively. Alfalfa production in 2003 was negatively impacted by a hailstorm, which occurred on 9 September. Alfalfa protein concentration averaged 21% with no significant differences among cultivars or irrigation treatments. Alfalfa relative feed value (RFV) increased as water stress intensity increased. Comparable results were obtained in 2002, although DM yield and RFV were higher in 2002 than in 2003. Overall, alfalfa DM yield increased linearly (R2 = 0.8) with increasing irrigation amount. The reverse was true vis-a-vis RFV. Alfalfa water use efficiency averaged 8.0, 8.3, and 7.1 kg of DM per mm of water (precipitation + irrigation + change in soil water) with the non-stressed, the moderately stressed, and the severely stressed treatment in 2003, respectively. Soil moisture was not monitored in 2002. Alfalfa DM production of 9.0 to 11.0 t/ha is achievable in the FS area of the Dolores Project. Current long-term average is closer to 7.1 t/ha. Water usage in the FS area averaged 1,489 mm per irrigated hectare of alfalfa in 1995 to 2001. This translates into an irrigation water use efficiency of 4.8 kg/mm. Total water use efficiency would be even lower, 3.8 to 4.0 kg/mm. This reflects the low efficiency of the predominant irrigation system (sideroll) in the FS area compared to SDI and the low alfalfa yield. |
| 2004 | A study was conducted in 2000 to 2004 to assess the feasibility of dryland cropping systems in southwestern Colorado and southeastern Utah. Precipitation was below normal every year of the study, except in 2004. Winter wheat after a 14-month fallow period produced the best seed yield in the driest years, 2000 and 2002, compared to more intensive crop rotations. This was due to more available soil moisture at planting, particularly with minimum- or no-till practices and adequate nitrogen fertilization. In years with timely precipitation, cropping systems which produced one crop per year or two crops per three years generally outperformed winter wheat-fallow. Examples are: winter wheat-bean in 2003 and winter wheat-corn-bean in 2003 and 2004. Corn appears to be a good crop in rotation with winter wheat and dry bean in southwestern Colorado, for unknown reasons. In general, spring crops performed poorly due to dry conditions in May, June, and July. Safflower depleted soil moisture more than corn or pinto beans. Our data suggest that winter wheat-safflower-fallow is preferable to winter wheat-safflower-bean in the project area. Chickpea did not do as well as expected in rotation with winter wheat. It was hypothesized that by planting and harvesting chickpeas early compared to pinto beans, winter wheat could be planted at a more optimum date after chickpeas than after pinto beans. Often chickpea seed maturity was delayed by frequent rain events in August or September, resulting in late harvest and poor seed quality. Chickpea showed promise in other trials but more research is needed to develop cultivars and management practices that are best suited to the environment of southwestern Colorado. Other crops should be tested as well to diversify production, with particular emphasis on meeting the demands of niche markets . Organic chickpea production appears to be profitable in southwestern Colorado. |
| 2005 | Alfalfa is an important crop in Colorado in general and southwestern Colorado in particular. With recent droughts and high fertilizer costs, Colorado producers are looking for ways to optimize water and fertilizer use. A study was conducted in 1995-2000 to determine the effects of four initial (pre-sowing) P (0, 37, 74, and 148 kg/ha) by three K (0, 93, and 186 kg/ha) fertilizer application rates on soil and plant P and K concentrations and alfalfa DM production in a calcareous soil. In addition, 37 kg P/ha were applied annually to half of each plot in the spring of 1997, 1998, and 1999. Potassium fertilization increased alfalfa dry matter (DM) yield significantly in 1996 only. Soil test K level was not impacted by K fertilization and remained above the critical level throughout the duration of the study. The initial P application did not affect alfalfa DM production significantly in 1996, 1997, 1998, and in total from 1996 through 1999. Conversely, the annual application of 37 kg P /ha increased alfalfa DM by a total of 3.2 Mg/ha in 1997 through 1999, when no P was applied initially. The initial and annual P fertilizer applications increased alfalfa P and soil AB-DTPA P concentrations significantly in 1997-1999 and 1998-2000, respectively. When no P was applied, soil test P level at the 0- to 15-cm depth dropped from 8.3 mg/kg at the initiation of the study in Aug. 1995 to less than 1.0 mg/kg at study termination in Apr. 2000 . Alfalfa yield response to P fertilizer was small even when soil test P level dropped to well below the critical level. No yield advantage was observed to maintaining soil test P above the critical level. A second study was conducted in 2002 and 2003 to evaluate the effect of water stress on alfalfa DM production and hay quality, using subsurface drip irrigation (SDI). Drip tapes were placed 45 cm below ground, at 152-cm lateral spacing. Low, moderate, and severe water stresses were imposed on three alfalfa cultivars with contrasting dormancy rating. In the least stressed treatment, soil water content in the root zone (0 to 1 .8 m) was maintained at approximately 50 % of available water capacity (AWC) throughout each growth period. In the moderate and severe stress treatments, soil water content was maintained at 50% AWC during the first two weeks of each growth period and at either 25% AWC (moderate) or 10% AWC (severe) thereafter. Alfalfa DM production averaged 12.8 Mg/ha in 2002 and 11.9 Mg/ha in 2003, with no significant differences among cultivars. It increased significantly with increasing amounts of irrigation. Alfalfa protein concentration averaged 21% in 2002 and 2003, with no significant differences among cultivars or irrigation treatments. Alfalfa relative feed value (RFV) was highest in the most stressed treatment and lowest in the least stressed treatment. It took 12.6 cm of water to produce 1.0 Mg of alfalfa hay in the least stressed treatment and 14.3 cm in the most stressed one. Visual observations indicate that 102-cm lateral spacing would be more suitable than 152-cm spacing. It would eliminate dips (low-growth middle area between tapes) in alfalfa growth by providing a more uniform water distribution. |
| 2006 | Most cropland in the Arkansas River Valley of southeastern Colorado is furrow-irrigated, but drip irrigation is gaining in importance due to diminishing water supplies and other considerations. A field trial was conducted at the Arkansas Valley Research Center (AVRC) in 2005 and 2006 to determine the effects of irrigation type, irrigation scheduling, and fertilizer rates on corn yield, N dynamics, and salt accumulation in the rootzone. Four N fertilizer rates (0, 67, 134, and 201 kg N/ha) and four manure rates (22, 44, and 68 Mg/ha) were compared using subsurface drip irrigation (SDI) and furrow irrigation (FrI) under full- and deficit-irrigation regimes. Drip tapes were placed 20 cm below the soil surface at 152-cm lateral spacing. There were no significant differences in grain yield between SDI and FrI in 2005 and 2006, even though 76% more water was applied with FrI in 2005 and 57% in 2006. Deficit irrigation decreased corn yield significantly in 2005 but not in 2006 due to more rainfall in 2006. Optimum yields were obtained with approximately 67 kg N/ha and 22 Mg of manure/ha in both years, while 68 Mg manure/ha depressed corn yield, particularly with SDI and deficit irrigation. Manure application increased soil salinity early in the season, which led to significantly lower plant populations with 44 and 68 Mg/ha in 2005 and 68 Mg/ha in 2006. Some salt accumulation was observed at the 1.2- to 1.8-m soil depth under SDI compared to FrI in the fall of 2005. There was also more residual soil nitrate-N under SDI at 201 kg N/ha and 22 and 44 Mg manure/ha in the fall of 2005 but not in the spring of 2006. Other studies conducted at AVRC in 2006 include several crop variety (hybrid) performance trials. Good to excellent seed and forage yields were observed in 2006 due to above-average precipitation, with the exception of winter wheat, which suffered from severe lodging late in the season. All the crops tested (alfalfa, Nuna bean, grain corn, corn silage, forage sorghum , winter canola, and winter wheat) were furrow-irrigated. Partial results are available at: http://www.colostate.edu/Depts/SoilCrop/extension/CropVar/index.html. |
| Impact | |
| 1999 | Based on the resuts of this study and numerous soil test results, it appears that K is not a limiting factor to alfalfa hay production in southwestern Colorado. Further data analysis should help determine P and K required to maintain soil test levels above the threshold at which a response to P or K would be expected. |
| 2000 | It is too early to make recommendations or assess the impact of this project on agriculture in the Four Corners area. Potential benefits include increased water use efficiency due to intensive crop rotations, reduced erosion due to less soil disturbance (minimum tillage), and reduced financial risk due to more crop diversification than has been the case. Farmers' participation in the field trials was excellent. |
| 2001 | Several well attended workshops and field days were generated as a result of this study, which could serve as the basis for implementing a water management assistance program in the Dolores Irrigation Project. Follow up research is being conducted to determine the effects of limited water supplies on alfalfa hay production and quality as well as develop best management strategies to address water shortages. |
| 2002 | Subsurface drip irrigation has the potential of enhancing irrigation water management in southwestern Colorado, but its use will depend largely on economic and practical considerations. |
| 2003 | Subsurface drip irrigation is not expected to replace sprinkler irrigation in the Dolores Project anytime soon, due to its high initial cost, high maintenance, and high management skill requirement. It does however show that vast improvements in water use efficiency in the Dolores Project are possible. More research is needed to refine SDI design and develop best management practices for crop production under the Dolores Project. Furthermore, strategies need to be developed to address water shortages. |
| 2004 | This study shows that minimum and no-till management practices can save valuable soil moisture in dry years. They will also curtail soil erosion which is a big concern in southwestern Colorado. The results also point to potential benefits of crop diversification and the need for long-duration research on cropping systems. |
| 2005 | Based on these and other research results, a response to K fertilization is unlikely on most alfalfa producing soils in Colorado, due to their high K buffering capacity. Our results suggest that annual P fertilizer application is superior to one-time application for irrigated alfalfa production on calcareous soils. Subsurface drip irrigation (SDI) produced comparable alfalfa hay yields to sprinkler irrigation. Drip tape lateral spacing of approximately 100 cm would ensure uniform water distribution and maximize hay production. Installation cost, maintenance requirements, and gopher control are some of the challenges that could impede the adoption of SDI by alfalfa hay producers in southwestern Colorado. |
| 2006 | The irrigation system by fertilizer rate study indicates that corn can be grown successfully with drip irrigation in the Arkansas River Valley. Drip irrigation would save substantial amounts of water, which could be used to irrigate more land or higher-value crops such as onions and cantaloupes. These and other vegetable crops are increasingly irrigated with SDI and are often grown in rotation with corn. Some of the challenges of drip irrigation in the Arkansas Valley are (1) getting enough water to the seedbed to ensure adequate seed germination and plant establishment, and (2) managing excess salts, particularly if well water is the irrigation water source since it generally contains a higher salt concentration than surface water. Top corn yields were obtained with as little as 67 kg N/ha or 22 Mg manure/ha; thus the potential exists for enhancing N fertilizer use efficiency and minimizing leaching of nitrate-N in the Arkansas Valley. The results of the crop variety performance trials are used by Arkansas Valley growers to select adapted varieties and hybrids. |
| Publications | |
| 1993 |
AL-KAISI, MAHDI, FISHER, A. G., LEIB, B. G., AND STACK, M.W. 1993. Evaporation of dry bean with a drip irrigation. p. 1179-1185. In R. G. Allen (ed.) Management of Irrigation and Drainage Systems. Amer. Soc. Civil Eng. LIEB, B. G., FERNANDEZ, D., AND FISHER, A. G. 1993. Frost protection design for fruit trees in Southwest Colorado. p. 48-55. In R. G. Allen (ed.) Management of Irrigation and Drainage Systems. |
| 1994 |
AL-KAISI, M. M. AND STACK, M. W. 1994. Crop response and irrigation scheduling evaluation under five levels of irrigation. In Agronomy Abstracts, Amer. Soc. of Agron., Madison, WI. p. 349 BERRADA, A. AND STACK, M. W. 1994. The feasibility of reduced tillage systems in southwestern Colorado. Agron. Abstracts, p. 348. Amer. Soc. of Agron., Madison, WI LIEB, BRIAN. 1994. Fruit tree response to micro-irrigation. p. 1-2. In the March issue The Waterline. Colorado State Univ., Cooperative Extension, Colorado River Salinity Control Project STACK, MARK W. 1994. SW Colorado Research Center Variety Testing. p. 4-5. In March issue The Waterline. Colorado State Univ., Cooperative Extension, Colorado River Salinity Control Project |
| 1995 |
BERRADA, A. 1995. Higher Yield, Acreage Potential Exists for Spring Grains in Southwest Colorado. In Montezuma Valley Journal, March 9, 1995 BERRADA, A. 1995. Tips on Establishing a Stand of Alfalfa. In The Waterline No. 82, May, 1995. Colo State Univ. Coop. Ext., Colorado River Salinity Control Project BERRADA, A., JOHNSON, D.L., SANFORD, D.V., and STACK, M.W. 1995. The Feasibility of Garbanzo Bean Production in Southwest Colorado. Agron. Abstracts p. 120, Amer. Soc. of Agron., Madison, WI BERRADA, A., STACK, M.W., SANFORD, D.V., and FISHER, A.G. 1995. Management Systems for Dryland Wheat and Bean Production in Southwestern Colorado- Conservation Tillage Project, 1989-93. Colo. Agric. Exp. Stn. Tech. Bull. TB95-2 FISHER, A.G., BRICK, M.A., WOOD, D.R., STACK, M., SCHWARTZ, H.F., OGG, J.B., PEARSON, C.H., SHANAHAN, J.F., and BALLARIN, M. 1995. Registration of 'Fisher' Pinto Bean. Crop Sci. 35:151 SMITH, K. and BERRADA, A. 1995. Production Management of Irrigated Alfalfa. In The Waterline No. 87, October, 1995. Colo State Univ. Coop. Ext., Colorado River Salinity Control Project. -- STACK, M.W., SANFORD, D.V., BERRADA, A. and QUICK, J.S. 1995. Irrigated Spring Wheat Variety Performance Test, 1989-94, Southwestern Colorado Research Center, Yellow Jacket, CO. Colo. Agric. Exp. Stn. Tech. Report TR95-5 |
| 1996 |
BERRADA, A., and SANFORD, D.V. 1996. Garbanzo bean test seems to offer alternative to pintos. p. 5 In Dove Creek Press, March 28, 1996 BERRADA, A., SANFORD, D.V., and STACK, M.W. 1996. Chickpea Response to Planting Rate and Rhizobial Inoculation under Variable Water Application Rates. Agron. Abstracts p. 116, Amer. Soc. of Agron., Madison, WI SANFORD, D.V. 1996. Salt Tolerant Forages. p. 5 In District Directions, The Dolores Soil Conservation District, Cortez, CO 81321 STACK, M.W., BERRADA, A., and SANFORD, D.V. 1996. Effects of Seeding Date, Seeding Rate, and Seed Treatment on Irrigated Winter Wheat. Agron. Abstracts p. 116, Amer. Soc. of Agron., Madison, WI |
| 1997 |
AL KAISI, MAHDI M., BERRADA, ABDEL, AND STACK, MARK. 1997. Evaluation of irrigation scheduling program and spring wheat yield response in southwestern Colorado. Agric. Water Management 34 (1997) 137-148. Elsevier Science Inc BERRADA, A. WESTFALL, D.G., SANFORD, D.V., AND STACK, M.W. 1997. Irrigated Alfalfa Response to P and K in Southwestern Colorado. Agron. Abstracts p. 230, Amer. Soc. of Agron., Madison, WI BERRADA, ABDEL. 1997. Highlights of Irrigation Management Survey in the Full Service Area of the Dolores Irrigation Project. Ag Research News, p. 1B In the Montezuma Valley Journal, Sept. 27, 1997 |
| 1998 |
BRICK, M.A., BERRADA, A., SCHWARTZ, H. F., and KRALL, J. 1998. Garbanzo bean production trials in Colorado and Wyoming. Colorado and Wyoming Agric. Exp. Stn. Tech. Bull. TB 98-2, Colorado State Univ. and Univ. of Wyoming |
| 1999 |
Al-Kaisi, Mahdi M., Berrada, Abdel F., and Stack, Mark W. 1999. Dry bean yield response to different irrigation rates in southwestern Colorado. J. Prod. Agric. 12:422-42 Berrada, A., Stack, Mark W., Riddell, Bruce, Brick, Mark A., and Johnson, Duane L. 1999. Chickpea: A Potential Crop for Southwestern Colorado. p. 206-213 In Jules Janick (ed). Perspectives on New Crops and New Uses, ASHS Press, Alexandria, VA. Proceedings of the Fourth National Symposium `New Crops and New Uses Biodiversity and Agricultural Sustainability', Phoenix, Arizona, November 8-11, 1998 Berrada, A., Westfall, D.G., Stack, M.W., and Hooten, T.M. 1999. Response of irrigated alfalfa to P and K rates. Agron. Abs. p. 245 Amer. Soc. of Agron., Madison, WI Hammon, R.W., Sanford, D.V., Stack, M.W., Berrada, A., and Peairs, F.B. 1999. Dryland winter wheat planting date and Russian wheat aphid studies in southwestern Colorado, 1990-1998. Tech. Rep. TR 99-2. Colorado State Univ., Ag. Exp. Stn., Dept. of Bioagric. Sci. and Pest Management , Southwestern Colorado Research Center, Fruita Research Cente |
| 2000 |
Berrada, A., and Peterson, G.A. 2000. Development of Sustainable Dryland Cropping Systems in SW Colorado and SE Utah. Agron. Abs. p. 132, Amer. Soc. of Agron., Madison, WI. |
| 2001 |
Berrada, A., Hooten, T.M., and Broner, I. 2001. Assessment of Irrigation Water Management and Demonstration of Irrigation Scheduling Tools in the Full Service Area of the Dolores Project: 1996-2000. Part II: Calibration of the Watermark Soil Moisture Sensor and ETgage Atmometer. Colorado Agricultural Experiment Station Technical Report Series, TR01-7, Colorado State Univ. , Ft. Collins, CO. Berrada, A., Hooten, T.M., Broner, I., and Cardon, G.E. 2001. Assessment of Irrigation Water Management and Demonstration of Irrigation Scheduling Tools in the Full Service Area of the Dolores Project: 1996-2000. Part III: Monitoring of Irrigated Alfalfa Fields Using the Watermark Moisture Sensor and ETgage Atmometer. Colorado Agricultural Experiment Station Technical Report Series, TR01-8, Colorado State Univ., Ft. Collins, CO. Berrada, A., Stack, M.W., and Cardon, G.E. 2001. Assessment of Irrigation Water Management and Demonstration of Irrigation Scheduling Tools in the Full Service Area of the Dolores Project: 1996-2000. Part I: Survey Results. Colorado Agricultural Experiment Station Technical Report Series, TR01-6, Colorado State Univ., Ft. Collins, CO. |
| 2002 |
Berrada, A. 2002. An In-Depth Look at Cropping Systems in SW Colorado and SE Utah. Agron. Abstracts, Amer. Soc. of Agron., Madison, WI. Berrada, A., Peterson, G.A., Ayers, P.D., Hooten, T.M., Hammon, R.W., Sharp, R.L., and Skouson , J. 2002. Developing Sustainable Dryland Cropping Systems in SW Colorado and SE Utah Using Conservation Tillage and Crop Diversification: 2000 & 2001 Results. Agric. Exp. Stn. Tech. Bull. TB02-2, Colorado State Univ., Ft. Collins, CO. |
| 2003 |
Berrada, A. 2003. Water management for optimum crop production in SW Coloado. Agron. Abstracts , Amer. Soc. of Agron., Madison, WI. (on CD-ROM). |
| 2004 |
Berrada, A. 2004. Developing Sustainable Dryland Cropping Systems in SW Colorado and SE Utah Using Conservation Tillage and Crop Diversification: 2002 and 2003 Results. Agric. Exp. Sta. Tech. Rep. TR04-02, Colorado State Univ., Ft. Collins, CO. Berrada, A. 2004. Results of Chickpea Research in Southwestern Colorado from 1994 to 2003. Agric. Exp. Sta. Tech. Rep. TR04-03, Colorado State Univ., Ft. Collins, CO. Berrada, A. 2004. Results of the Irrigated Winter Triticale at Yellow Jacket 1996-1999. p. 95-100 In J.E. Brummer and C.H. Pearson (ed.) Colorado Forage Research 2003: Alfalfa, Irrigated Pastures, and Mountain Meadows. Agric. Exp. Sta. and Coop. Ext. Tech. Rep. TR04-01, Colorado State Univ., Ft. Collins, CO. Berrada, A., and Brummer, J.E. 2004. Evaluation of Spring Cereals for Dual Use. p. 101-106 In J.E. Brummer and C.H. Pearson (ed.) Colorado Forage Research 2003: Alfalfa, Irrigated Pastures , and Mountain Meadows. Agric. Exp. Sta. and Coop. Ext. Tech. Rep. TR04-01, Colorado State Univ., Ft. Collins, CO. |
| 2005 |
Berrada, A. 2005. Alfalfa Response to Water Deficit Using Subsurface Drip Irrigation. Agric. Exp. Stn. Tech. Bull. TB05-01, Colorado State Univ., Ft. Collins, CO. Berrada, A., and Westfall, D.G. 2005. Irrigated Alfalfa Response to Phosphorus and Potassium in a Calcareous Soil. Communications in Soil Science and Plant Analysis, 36: 1213-1227. |
| 2006 |
Berrada, A., Halvorson, A.D., Bartolo, M.E., Valliant, J. 2006. The effect of manure and N rates on corn yield and salt and nitrate movement in the soil under furrow and drip irrigation in the Arkansas River Valley. p. 264-269 In A.J. Schelegel (ed.) Great Plains Soil Fertility Conference Proceedings, vol. 11, March 7-8, 2006, Denver, CO. Berrada, A., Halvorson, A.D., Bartolo, M.E., Valliant, J. 2006. The effects of subsurface drip and furrow irrigation on the movement of salts and nitrate in the root zone. p. 1-13 In Proceedings of the 27th International Irrigation Show, 5-7 Nov. 2006, San Antonio, TX. The Irrigation Association. Berrada, A., Johnson, J.J. 2006. Irrigated winter wheat planting date study at Rocky Ford in 2005. p.29-31 In J.J. Johnson (ed.) Making Better Decisions: 2005 Colorado Winter Wheat Variety Performance Trials. Agric. Exp. Sta. Tech. Rep. TR06-09, Colorado State Univ., Ft. Collins, CO. Contributed to several other crop testing publications in Colorado. Halvorson, A.D., Bartolo, M., Reule, C.A., Berrada, A. 2006. Onion Response to mitrogen fertilization under drip and furrow irrigation. Proceedings National Allium Research Conference. December 7-8, 2006, College Station, TX p. 73-78. Halvorson, A.D., Bartolo, M., Reule, C.A., Berrada, A. 2006. Drip versus furrow irrigation for onion production in the Colorado Lower Arkansas River Valley. Soil and Water Conservation Society. Abstract. July 22-26-2006, Keystone, CO. J. Soil and Water Conserv. 61(3):229. Halvorson, D., Bartolo, M.E., Reule, C.R., Berrada, A. 2006. Onion response to nitrogen fertilization under drip and furrow irrigation. p. 7-12 In A.J. Schelegel (ed.) Great Plains Soil Fertility Conference Proceedings, vol. 11, March 7-8, 2006, Denver, CO. Larson, K.J., Berrada, A., Thompson, D.L. 2006. Sorghum hybrid performance trials in Colorado, 2005. Agric. Exp. Sta. Tech. Rep. TR06-04, Colorado State Univ., Ft. Collins, CO. |