Nigh and Courtin (1998) years-to-breast-height model for red alder

Implementation of the Nigh and Courtin (1998) years-to-breast-height model for red alder (ALNU.RUB) in coastal British Columbia.

Usage

ytbh_nighcourtin1998(si)

Arguments

si

Numeric vector. Site index SI25 (m at breast-height age 25 years).

Value

A tibble with one column:

ytbh

Predicted years to breast height (years).

Details

The source relation is piecewise: $$ YTBH = 5.494 - 0.1789 \times SI25, \quad SI25 \le 25 $$ $$ YTBH = 1.0, \quad SI25 > 25 $$

References

Nigh, G. D., & Courtin, P. J. (1998). Height models for Red Alder (Alnus rubra Bong.) in British Columbia. New Forests, 16, 59-70.

Examples

ytbh_nighcourtin1998(
  si = c(12, 20, 28)
)
#> # A tibble: 3 × 1
#>    ytbh
#>   <dbl>
#> 1  3.35
#> 2  1.92
#> 3  1