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Current guidance and equipment technologies permit anhydrous ammonia (NH₃) to be confidently placed parallel to crop rows in both before- and after-planting situations at shallower depths than traditional applications. Field studies from 2010 to 2012 investigated the effects of pre-plant vs. side-dress NH₃ at four N rates (0, 90, 145, and 202 kg N ha–¹) on maize (Zea mays L.) grain yield (GY), N recovery efficiency (NRE), and N use efficiency (NUE). All NH₃ was injected to a 12-cm depth; pre-plant NH₃ was banded parallel to, but approximately 15 cm offset from, intended rows a few days before planting. Side-dress NH₃ was applied to mid-row positions at the V6–V7 growth stage. Whole-plant N uptake at maturity was consistently higher with pre-plant application. Highest GY was observed at the highest N rate with side-dress timing in 2011 but with the pre-plant timing in 2012. Relative to side-dress, pre-plant application improved average NRE across N rates from 0.53 to 0.72 kg plant N kg–¹ applied N during the 3-yr period. Overall NUE levels in 2012 were 50% lower than in 2010 and 40% lower than in 2011 due to drought, yet NRE doubled and NUE more than tripled with pre-plant relative to side-dress application. This 3-yr study highlights the inability of either one-time NH₃ application strategy investigated to consistently have the highest GY and NUE as well as the dominating year-specific influences of both N timing and N rates on NRE.

With the advent of precision guidance systems, maize (Zea mays L.) farmers in various tillage systems have more options in pre-plant nutrient banding relative to the intended crop rows. Anhydrous ammonia (NH₃) placement during pre-plant application is of interest because of concerns for possible ammonia toxicity to maize seedlings when high NH₃ rates are applied too close to the seed row and the need to improve plant-nitrogen (N) use efficiencies. Field studies were conducted between 2010 and 2012 near West Lafayette, IN, to compare traditional angled (diagonally) vs. precision-guided parallel NH₃ applications (the latter was offset 15 cm from the future row) in no-till and conventional tillage systems. The NH₃ was injected to depths of about 12 cm at N rates of 145 and 202 kg N ha–¹. Maize was planted with additional starter N (20 kg N ha–¹) within 6 d of NH₃ application. Neither NH₃ application placement resulted in significant maize seedling mortality. Conventional tillage increased mean grain yields across N rates and placement treatments from 10.6 to 11.6 Mg ha–¹. Tillage did not impact reproductive-stage leaf chlorophyll content (SPAD), or whole-plant N content at maturity when NH₃ was parallel applied, but these plant responses were significantly lower in no-till after diagonal application. Lowering the pre-plant N rate to 145 from 202 kg N ha–¹ significantly lowered maize whole-plant biomass and N accumulation at maturity with diagonal application, but not when NH₃ was parallel applied.

Fluid P fertilizers are commonly applied to established alfalfa (Medicago saliva L.) despite their higher cost compared to granular forms. The objectives of this experiment were to compare effects of fluid and granular P fertilizer on alfalfa yield, and availability and movement of P in the soil. The P fertilizers compared were fluid ammonium polyphosphate (APP, 10-34-0) applied in irrigation water and granular monoammonium phosphate (MAP, 11-52-0) topdressed and incorporated by flood irrigation on a calcareous soil at Maricopa, AZ. Fertilizer P was applied each December at rates of 1,2,3, and 5 g P m -2 . The soil was sampled about 1 mo later. In the first four cuttings of the first year, hay yields were 1358 g m -2 for APP and 1501 g m -2 for MAP. No differences in yield due to P source were measured in the remaining four cuttings of the first year, or in any cutting the second or third year. In the surface soil (0-7.6 cm), the bicarbonate extractable soil P averaged 44 mg kg -1 for APP and 7.1 for MAP. The depth of movement of the fertilizers was similar except in the first year where MAP moved deeper into the soil profile than APP. In this study, the higher cost of fluid APP compared with granular MAP was not recovered by increased yield. However, at low P rates, water-run APP may be more economical than topdressed MAP due to its low application cost.

Numerous proximal and remote soil and plant‐testing methods are available to guide variable‐rate N management in maize production. These include preseason and late spring soil nitrate tests, late season stalk nitrate tests, handheld chlorophyll meter readings, remote sensing of soil and crop canopy properties, site‐specific data from yield monitors and soil electrical conductivity maps. Field applicators have even been equipped to sense the N status of a crop and direct the application of any needed N on‐the‐go. However, the adoption rates of variable‐rate N management are low worldwide despite the potential economic and environmental benefits of this practice and the availability of variable‐rate application technology in key areas of maize production. A major obstacle is the finding that recommended N fertilizer rates based on yield goal are often poorly correlated with actual economically optimum N rates. Nitrogen response patterns are often field and season specific and can vary widely within...

The goal of this research was to determine the potential for use of site-specific management of corn hybrids and plant densities in dryland landscapes of the Great Plains by determining (1) within-field yield variation, (2) yield response of different hybrids and plant densities to variability, and (3) landscape attributes associated with yield variation. This work was conducted on three adjacent fields in eastern Colorado during the 1997, -98, and -99 seasons. Treatments consisted of a combination of two hybrids (early and late maturity) and four plant densities (24,692, 37,037, 49,382 and 61,727 plants ha )1 ) seeded in replicated long strips. At maturity, yield was measured with a yield-mapping combine. Nine landscape attributes including elevation, slope, soil brightness (SB) (red, green, and blue bands of image), ECa (shallow and deep readings), pH, and soil organic matter (SOM) were also assessed. An analysis of treatment yields and landscape data, to assess for spatial dependency, along with semi variance analysis, and block kriging were used to produce kriged layers (10 m grids). Linear correlation and multiple linear regression analysis were used to determine associations between kriged average yields and landscape attributes. Yield monitor data revealed considerable variability in the three fields, with average yields ranging from 5.43 to 6.39 mg ha )1 and CVs ranging from 20% to 29%. Hybrids responded similarly to field variation while plant densities responded differentially. Economically optimum plant densities changed by around 5000 plants ha )1 between high and low-yielding field areas, producing a potential savings in seed costs of $6.25 ha )1 . Variability in yield across the three landscapes was highly associated with landscape attributes, especially elevation and SB, with various combinations of landscape attributes accounting for 47% ,9 5%, and 76% of the spatial variability in grain yields for the 1997, -98, and -99 sites, respectively. Our results suggest site-specific management of plant densities may be feasible.

Adoption of variable-rate N management by North American corn (Zea mays L.) producers is low, despite the potential economic and environmental benefits of this practice. A major obstacle is that recommended N fertilizer rates based on yield goal are often poorly correlated with actual economically optimum N rates. Nitrogen response patterns are often field- and season-specific and can vary widely within the same field, further complicating adoption. Side-by-side comparisons of uniform- and variable-rate N management have revealed no consistent advantages for either strategy in yields achieved, profitability, whole-field N usage, or N-use efficiency by plants. In the future, a better understanding of temporal variation in N soil test levels, better crop simulation models, and improved N sensing and application equipment may assist growers in capturing the benefits of site-specific N management.

Production of broccoli (Brassica olearacea L. Italica ) in the south-western USA is highly dependent on inputs of water and N fertilizer to achieve optimum yields and quality. The water and N-response characteristics of subsurface drip-irrigated broccoli have not previously been reported. Field experiments were conducted in southern Arizona during 1993 through 1996. The objectives were to determine: (i) subsurface drip-irrigated broccoli response to a range of soil water tension (SWT), (ii) effects and interactions of water and N fertilizer inputs on crop yield and quality, and (iii) seasonal and daily N uptake. Experiments consisted of factorial combinations of three irrigation regimes (low, medium, and high) and four N rates (60-500 kg N ha -1 ). Irrigation was applied daily to maintain target SWT, and all N was applied by fertigation. With respect to marketable yield, the optimum SWT was 10 kPa in this sandy loam soil, as indicated by response surface models. Marketable yields across all treatments ranged from 18 Mg ha -1 . Marketable yield was significantly affected by N rate during all three seasons, and by SWT during two of three seasons. There were no significant SWT x N interactions for marketable yield. Quality parameters (head weight and diameter) were much more responsive to N rate than to SWT, and there were few significant SWT x N interactions for broccoli quality. Broccoli accumulated up to 320 kg N ha -1 in the aboveground biomass, and N uptake fluxes were as high as 5 kg N ha -1 d -1 at the first bud growth stage (825-1000 heat units after planting [HUAP]).

Nitrogen fertilization and irrigation practices can affect durum [Triticum turgidum subsp. durum (Desf.) Husn.] grain quality, especially protein content. The purpose of this study was to determine if irrigation frequency during grain fill influences the effectiveness of N applied near anthesis in increasing durum grain quality. A field study was conducted at Maricopa, AZ on a Casa Grande sandy loam soil (fine-loamy, mixed, superactive, hyperthermic, Typic Natrargid). Durum was grown with recommended amounts of N fertilizer until anthesis when 0, 3.4, and 6.7 g N m -2 were applied and irrigation based on 30, 50, and 70% depletion of plant-available soil water was initiated. Irrigation during grain fill had no effect on grain yield or grain quality except in 1996, when irrigating at 30, 50, and 70% depletion resulted in hard vitreous amber counts (HVAC) of 813, 870, and 934 g kg -1 , respectively. Nitrogen application near anthesis of 0, 3.4, and 6.7 g N m -2 resulted in grain protein contents of 115, 127, and 140 g kg -1 in 1995 and 132, 141, and 151 g kg -1 in 1996, respectively. Nitrogen application near anthesis increased grain protein yield and HVAC in both years of the study and increased grain yield, grain volume weight, and kernel size in 1995. The results of this study suggest that N fertilizer application near anthesis has a primary influence on durum quality and that effects of irrigation frequency during grain fill are inconsistent or relatively minor.

Water x N rate experiments were conducted on subsurface drip-irrigated cauliflower (Brassica olearacea L. var. botrytis L.) during three winter growing seasons in southern Arizona. A range of water and N rates were selected to permit the calculation of appropriate water × N production functions. The objectives were to (i) determine the effects and interactions of irrigation water and N inputs on crop N uptake, residual soil NO 3 -N, N-use efficiency, and unaccounted fertilizer N, and (ii) evaluate agronomic, economic, and environmental production criteria during three growing seasons. Spatial analysis was used to identify overlap of acceptable zones of marketable yield, net return, and unaccounted fertilizer N within each growing season. Acceptable yields and net return were defined as ≥95% of the maximum predicted response within the range of the treatments; acceptable unaccounted fertilizer N was defined as ≤ 40 kg ha -1 . Net returns and aboveground plant biomass N were significantly affected (P < 0.01) by N rate and in 2 yr by irrigation. There were also significant irrigation treatment x N rate interactions for net returns and biomass N. Residual soil NO 3 -N concentrations increased with N rate and decreased with soil water tension (SWT). Average amounts of residual soil NO 3 -N (0-0.9 m) for the highest N rate during the three seasons were 317, 296, and 180 kg ha -1 for the low, medium, and high irrigation treatments, respectively. Unaccounted fertilizer N was significantly affected (P < 0.05) by irrigation treatment, N rate, and irrigation treatment x N rate interactions each year. Overlap of acceptable zones of marketable yields, net returns, and unaccounted N was achieved in one of the three years. The single combination of SWT and N rate that came closest to producing optimal or near-optimal agronomic, economic, and environmental outcomes in all three years was 10 to 12 kPa and 350 to 400 kg N ha -1 .

Production of cauliflower (Brassica olearacea L. var. botrytis L.) in the southwestern U.S. is highly dependent on inputs of water and N fertilizer to achieve optimum yields and quality. Subsurface drip irrigation offers what is likely the ultimate in control of the plant root zone for crop production. However, the water and N-response characteristics of subsurface drip-irrigated cauliflower have not previously been reported. Three field experiments were conducted in southern Arizona in 1993-1996. The objectives were to determine: (i) an optimum range of soil water tension for subsurface drip-irrigated cauliflower, (ii) the effects and interactions of water and N fertilizer on crop yield and quality, and (iii) seasonal and daily N uptake for high-yielding cauliflower. The experiments were randomized complete block factorial with three irrigation regimes (low, medium, high), four N rates (60-600 kg N ha -1 ), and four replications. Irrigation was applied dally to maintain target soil water tensions and all N was applied by fertigation. With respect to marketable yield, curd weight, and curd diameter, the optimum soil water tension was approximately 10 to 12 kPa in this sandy loam soil during the 3 years. Marketable yields across all treatments ranged from 30 Mg ha -1 . Yields and quality were generally more responsive to N rate than to irrigation and showed significant irrigation by N rate interactions during 2 of the 3 years. At equivalent N rates, excessive irrigation generally resulted in lower yields and quality. Cauliflower accumulated up to 250 kg N ha -1 in the aboveground biomass and N-uptake fluxes were as high as 5 kg N ha -1 d -1 at the 12-leaf to folding growth stage.

Yield monitoring and mapping are becoming commonplace with many crops throughout North America. Some fields now have a 3- to 5-yr yield map history. A yield map, however, only documents the spatial distribution of crop yield and does not explain what factor(s) caused the variation. The goal of yield map interpretation is enhanced profitability through better understanding and control of natural and management-induced sources of yield variation. Numerous causes of crop yield variation have been documented, including climate, soil-water relationships, soil physical and chemical properties, site attributes, crop pest infestations, crop inputs and condition, field history, and cultural practices. Proper visual presentation of yield monitor data in yield map form and the accurate identification of characteristic patterns of yield variation are essential for meaningful interpretation of the yield map. Unfortunately, all yield monitor data sets and maps contain inherent error, some of which cannot be easily corrected. Error-induced patterns must be separated from real yield variation in order to make correct interpretations. In general, irregular areas, blotches or, speckles, and elliptical patterns are the result of naturally occuring yield-limiting factors. Conversely, rectangles, abrupt boundaries, circles, arcs, and streaks or lines reflect management-induced patterns of yield variation. In addition, divergence of parallel swaths, missing data points, and a repeating sawtooth pattern along field margins usually result from errors associated with Global Positioning System (GPS) signal reception and yield monitor data collection. Yield map interpretation is greatly enhanced by ongoing grower involvement and the insightful use of auxiliary agronomic, spatial, and historical site information. Geographic Information System (GIS) tools are virtually essential to evaluate multiple layers of spatial data. GIS software can be used to systematically and quantitatively evaluate the relationships between yield data and other spatial features. In the future, tools such as data-mining software, and other sophisticated mathematical and spatial models may provide additional power to interpret single-year as well as multi-year yield map information.

Nitrogen (N) in a soil that is not immediately taken up by a crop is subject to leaching, denitrification and other mechanisms of loss. Nitrogen uptake studies identify the total amount of N accumulated by the crop and the period of peak demand. This information can be used to devise management strategies aimed at supplying N preceding anticipated uptake. Split sidedress application, fertigation, and use of controlled release fertilizers (CRN) are all viable options for N management, depending on the crop production scenario and available infrastructure. Soil and plant tissue testing can be useful feedback tools for adjusting N applications for soil contributions of N and unexpected N losses. Efficient irrigation is of paramount importance in achieving efficient N fertilization regardless of management practice.

Not all fields, nor even portions of fields, have the same economically optimal corn plant density. However, until the recent introduction of precision farming, producers could not benefit from these accepted intrafield differences. This field study was conducted on 170 cooperating farmer fields throughout the Midwestern U.S. Corn Belt between 1987 and 1996 and consisted of over 42 000 individual experimental units. At each location, corn (Zea mays L.) was overplanted and thinned to 44 000 to 104 000 plants ha -1 . The objective of our field research was to estimate the economic value, to the farmer, of variable rate seeding (VRS) as compared with uniform rate seeding (URS). We first estimated the correlation between field quality and economically optimal plant density. The economically optimal uniform plant density for the Midwest Corn Belt was 67 900 plants ha -1 . For every tonne per hectare increase in site quality, as measured by yield potential, the predicted value of the site-specific economically optimal plant density increased by approximately 1200 plants ha -1 . We compared differences in revenues minus seed costs on four simulated fields. The value of VRS, ignoring the costs of VRS equipment and services, ranged from $12.83 ha -1 for farmers with VRS technology and full information to $0.15 ha -1 for farmers with VRS technology but only partial information. Profitable implementation of VRS will require detailed and expensive information regarding site characteristics, production inputs, and stochastic factors. Therefore, VRS will remain economically infeasible for most commercial corn growers until the cost of obtaining such information decreases considerably.

Nitrogen (N) status of vegetable crops is often monitored by analysis of dried plant tissues. However, dry tissue analysis often causes a significant delay between sampling and analysis. This study was conducted to examine the accuracy of a portable nitrate meter for determining petiole sap nitrate (NO3) contents, and the relationship between NO3‐N concentration in fresh petiole sap and in dried petiole tissue of broccoli grown in southern Arizona during the 1993–94 and 1994–95 winter growing seasons. Experiments were factorial combinations of three irrigation rates and four N rates, both ranging from deficient to excessive. Petioles were sampled throughout each season, and split for sap and dry tissue analysis. A linear correlation was obtained between the two measurements in both seasons, with no consistent effect due to irrigation treatment or crop maturity. The regression coefficients did not differ among seasons. Therefore, a combined regression equation: Y=343+0.047X (r2 = 0.799) was derive...

This study was conducted to evaluate the accuracy of sap analysis using a portable nitrate ion meter for cauliflower ( Brassica oleracea L. Botrytis Group, cv. Candid Charm) petiole nitrate determination. The relationship between NO 3-N concentration in fresh petiole sap and in dried petiole tissue was studied for cauliflower grown in southern Arizona during the 1993-94 and 1994-95 growing seasons. Experiments were factorial combinations of three water rates and four N rates, both ranging from deficient to excessive. Petioles were collected throughout each season and were split for analysis of sap NO3-N and dried petiole NO3-N. Linear correlations between the two methods were similar in both seasons, with no consistent effect due to water application rate or crop maturity. Therefore, a single regression equation was derived: petiole sap NO 3-N (mgliter -1 ) = 0.047 × dry petiole NO3-N (mgkg -1 ) + 218 (r 2 = 0.772). This equation can be used to relate sap test measurements to existing guidelines for NO 3-N concentrations in cauliflower petioles. These results suggest that the quick sap test, using the portable nitrate ion meter, is a valuable technique for monitoring N status of cauliflower. sica oleracea L. Capitata Group) (Scaife and Stevens, 1983), and other vegetable crops (Prasad and Spiers, 1984). A recently devel- oped portable nitrate-selective electrode that can directly measure NO3-N in fresh petiole sap may have potential for near real-time mea- surements. Westcott et al. (1993) obtained a coefficient of determination (r 2 ) of 0.925 for the relationship between the sap test and dry tissue analysis for potato. They suggested us- ing a regression equation to convert sap test results to dry tissue NO 3-N concentrations. Hodges and Baker (1993) evaluated the sap test for cotton ( Gossypium hirsutum L.) and observed that it was highly correlated with dry tissue analysis only at the early growth stages. Hartz et al. (1994) compared petiole sap NO3-N using a portable electrode with dry tissue analysis for broccoli ( Brassica oleracea L. Italica Group), celery ( Apium graveolens L.), corn (Zea mays L.), lettuce ( Lactuca sa- tiva L.), pepper (Capsicum annuum L.), to- mato (Lycopersicon esculentum Mill.), and

Evaluation of trickle-irrigated crop production systems should address agronomic, economic, and environmental outcomes. The objectives of this research were to : (i) determine plant N uptake, residual soil inorganic N, unutilized fertilizer N, and unaccounted fertilizer N for subsurface trickle irrigated leaf lettuce (Lactuca sativa L. cv. Waldmann's Green), and (ii) use spatial analysis techniques to simultaneously evaluate agronomic, economic, and environmental production criteria for leaf lettuce within one growing season. Field experiments were conducted using buried trickle irrigation during three winter growing seasons in southern Arizona. Deficient to excessive N (35-300 kg ha -1 ) and target soil water tension (SWT) treatments (12.0-4.0 kPa) were applied in factorial combinations each year. Fertilizer N recovery was determined by the difference method. Spatial analysis of response surfaces was used to determine overlap of zones with acceptable values for marketable yield, net economic return, and unaccounted fertilizer N for leaf lettuce during 1992-1993. Maximum unutilized fertilizer N was 216 kg ha -1 for leaf lettuce, and maximum unaccounted fertilizer N was 149 kg ha -1 . Unutilized fertilizer N and unaccounted fertilizer N increased sharply when adequate N and water rates were exceeded. Spatial analysis of response surfaces for 1992-1993 showed a small region bounded by 6.6 to 7.3 kPa SWT and 238 to 252 kg N ha -1 that would have resulted in >95% of maximum predicted marketable yield and net return while limiting NO 3 -N concentrations in drainage water to ≤10 mg L -1 .

Rising water costs and concerns about groundwater contamination by NO 3 - are forcing growers in arid regions to adopt practices to improve water and N use efficiency. Subsurface trickle irrigation offers the ability to precisely deliver appropriate amounts of water and N to the crop root zone. The objectives of this research were to : (i) determine the optimum level (with respect to marketable yield) of soil water tension for subsurface trickle-irrigated leaf lettuce (Lactuca sativa L. cv. Waldmann's Green), (ii) determine N by water interactions on crop yield and quality, and (iii) determine seasonal patterns of crop N uptake. Three field experiments were conducted during the 1990 to 1993 winter growing seasons on a Casa Grande soil (fine-loamy, mixed, hyperthermic, Typic Natriagid [reclaimed]) in southern Arizona. Deficient to excessive N (35-300 kg ha - 1 ) and target soil water tension (SWT) treatments (12.0-4.0 kPa) were applied in factorial combinations each year. Maximum marketable leaf lettuce yields observed were 54.0 Mg ha -1 . Nitrogen rates associated with maximum yields ranged from 120 to 300 kg ha -1 , and depended on average SWT. Excessive irrigation (5.3 kPa average SWT) resulted in lower yields, head weight, and head length. Marketable yields showed a pronounced water x N interaction, but yield quality (head length and weight) did not. Maximum N flux was 4.3 kg ha -1 d -1 , and an average of 75% of total N accumulation occurred in the 38 d prior to harvest. Results suggest that the soil water tension at 0.3-m depth should be maintained at 6 to 7 kPa for optimum yields of trickle-irrigated leaf lettuce.

Three field experiments using subsurface trickle irrigation with various rates of target soil water tension (SWT) and N rates were conducted in southern Arizona during 1990–93. The experiments were conducted with collard (Brassica oleracea L. Acephela Group cv. Vates), mustard [Brassica juncea (L.) Czerniak cv. Southern Giant], and spinach (Spinacea oleracea L. cv. Indian Summer). The interactive effects of water and N treatments on crop yield, N uptake, and unutilized fertilizer N were studied. In general, excessive irrigation (SWT

Two field experiments were conducted with subsurface trickle-irrigated romaine lettuce (Lactuca sativa L. cv. Parris Island Cos) during the 1990–92 winter growing seasons in southern Arizona. The objectives were to determine 1) yield and quality response to varying combinations of soil water tension (SWT) and N fertilizer, 2) seasonal patterns of N uptake, and 3) unutilized fertilizer N. During 1990–91, N rates were 35, 120, and 205 kg·ha–1. During 1991–92, the experiment was factorial with N levels from 50 to 300 kg·ha–1 and target SWT levels of 7.0 and 4.0 kPa. Unutilized fertilizer N was the difference between fertilized and nonfertilized plots in total N inputs not harvested in the crop. When excessive irrigation was not applied (SWT between 6.5 and 7.4 kPa), 95% of the maximum crop yield and yield quality (head length and fresh mass) response occurred at N rates of 156 to 193 kg·ha–1, with unutilized fertilizer N –1. Excessive irrigation (4.6 kPa) resulted in lower yields and yield quality and higher unutilized fertilizer N. Romaine accumulated >74% of its total N uptake in the 38 days before harvest. Unutilized fertilizer N increased sharply when adequate N and water rates were exceeded. These results suggest that a target SWT of no wetter than 6.5 kPa is appropriate for subsurface trickle-irrigated romaine lettuce.

Attempts to characterize the N status of irrigated spring wheat (Triticum aestivum L.) using basal stem nitrate-N (NO 3 -N) tissue tests have shown contradictory results due to the narrow range of agronomic conditions existing in most studies. Five field experiments were conducted in southern Arizona to examine the effects of N rate, mobility of N fertilizer form, residual soil N, soil texture, and two contrasting cultivars on basal stem NO 3 -N concentrations, yield and quality of irrigated durum wheat (Triticum turgidum L. var. durum (...)

Intensive N management for irrigated spring wheat (Triticum aestivum L.) grown in arid and semi-arid regions requires preplant soil, plus periodic basal stem analyses for nitrate. Additional information on the relationships betwween grain yield and quality, N rates and stem nitrate-N (NO 3 -N) levels is needed for the wide range of agronomic conditions found in areas where irrigated durum wheat (Triticum turgidum L. var. durum) is grown (...)