Plant Types

SWAT+ categorizes plants into seven different types: warm season annual legume, cold season annual legume, perennial legume, warm season annual, cold season annual, perennial and trees. The differences between the different plant types, as modeled by SWAT+, are as follows:

1. warm season annual legume:

-simulate nitrogen fixation

-root depth varies during growing season due to root growth

2. cold season annual legume:

-simulate nitrogen fixation

-root depth varies during growing season due to root growth

-fall-planted land covers will go dormant when daylength is less than

the threshold daylength

3.perennial legume:

-simulate nitrogen fixation

-root depth always equal to the maximum allowed for the plant species and soil

-plant goes dormant when daylength is less than the threshold daylength

4.warm season annual:

-root depth varies during growing season due to root growth

5.cold season annual:

-root depth varies during growing season due to root growth

-fall-planted land covers will go dormant when daylength is less than the threshold

daylength

6.perennial:

-root depth always equal to the maximum allowed for the plant species and soil

-plant goes dormant when daylength is less than the threshold daylength

7. trees:

-root depth always equal to the maximum allowed for the plant species and soil

-partitions new growth between leaves/needles and woody growth

-growth in a given year will vary depending on the age of the tree relative to the

number of years required for the tree to full development/maturity

-plant goes dormant when daylength is less than the threshold daylength

Table 5:1-3: SWAT+ input variables that pertain to plant type.

Variable Name	Definition	Input File
IDC	Land cover/plant classification: 1.warm season annual legume 2.cold season annual legume 3.perennial legume 4.warm season annual 5.cold season annual 6.perennial 7.trees	crop.dat