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Look up California N application rates by crop

Source: R/look_up_ca_n_rate.R
look_up_ca_n_rate.Rd

Returns recommended nitrogen application rate ranges for California crops. Rates are provided in both imperial (lbs N/acre) and SI (g N/m2) units.

Usage

look_up_ca_n_rate(crop, pft_group = NULL, unit = c("g_m2", "lbs_acre"))

Source

Rosenstock, T. S., Liptzin, D., Six, J., & Tomich, T. P. (2013). Nitrogen fertilizer use in California: Assessing the data, trends and a way forward. California Agriculture, 67(1). https://escholarship.org/uc/item/5mk2q1sm

Meyer, R. D., Marcum, D. B., Orloff, S. B., & Schmierer, J. L. (2007). Alfalfa fertilization strategies. UC ANR Publication 8296.

Arguments

crop

Character string. Crop name to look up.

pft_group

Optional character string. Filter results to a specific plant functional type group (e.g. "row", "woody", "rice").

unit

Character, one of "g_m2" (default) or "lbs_acre". Controls which columns appear as `min_n` and `max_n` in the output.

Value

A tibble with columns: `pft_group`, `crop`, `min_n`, `max_n`, `source`. The `min_n` and `max_n` columns are in the requested unit. Returns an empty tibble (with warning) if no match is found.

Details

Matching is case-insensitive. Exact matches are returned directly. If no exact match is found, partial matching is used to suggest possible crops and an empty data frame is returned.

See also

[look_up_fertilizer_components()] for fertilizer nutrient composition (N/C fractions) from the SWAT/DayCent database. [ca_n_application_rate] for the underlying dataset.

Examples

look_up_ca_n_rate("Tomatoes, Processing")
#> # A tibble: 1 × 5
#>   pft_group crop                 min_n max_n source                 
#>   <chr>     <chr>                <dbl> <dbl> <chr>                  
#> 1 row       Tomatoes, processing  11.2  16.8 Rosenstock et al., 2013
look_up_ca_n_rate("corn")
#> # A tibble: 1 × 5
#>   pft_group crop  min_n max_n source                 
#>   <chr>     <chr> <dbl> <dbl> <chr>                  
#> 1 row       Corn   16.8  30.8 Rosenstock et al., 2013
look_up_ca_n_rate("wheat", unit = "lbs_acre")
#> # A tibble: 1 × 5
#>   pft_group crop  min_n max_n source                 
#>   <chr>     <chr> <dbl> <dbl> <chr>                  
#> 1 row       Wheat   100   240 Rosenstock et al., 2013
look_up_ca_n_rate("pistachios", pft_group = "woody")
#> # A tibble: 1 × 5
#>   pft_group crop       min_n max_n source                 
#>   <chr>     <chr>      <dbl> <dbl> <chr>                  
#> 1 woody     Pistachios  11.2  25.2 Rosenstock et al., 2013