# var

The following condition variables are currently coded in SWAT+. If a condition field is not listed in 'Additional fields used', you may leave it as null if field type is string or 0.0000 if field type is double/real.

<table><thead><tr><th width="187">Condition variable</th><th width="202.33333333333331">Description</th><th width="202">Additional fields used</th><th width="209.66666666666669">Comments</th></tr></thead><tbody><tr><td>w_stress</td><td>Water stress of the plant(s)</td><td><a href="/pages/96M0WrCeHZgzuaeW9O5B">lim_const</a></td><td>If more than one plant is growing, the average stress will be used</td></tr><tr><td>n_stress</td><td>Nitrogen stress of the plant(s)</td><td><a href="/pages/96M0WrCeHZgzuaeW9O5B">lim_const</a></td><td>If more than one plant is growing, the average stress will be used</td></tr><tr><td>p_stress</td><td>Phosphorus stress of the plant(s)</td><td><a href="/pages/96M0WrCeHZgzuaeW9O5B">lim_const</a></td><td>If more than one plant is growing, the average stress will be used</td></tr><tr><td>phu_plant</td><td>Plant Heat Units since start of plant growth</td><td><a href="/pages/96M0WrCeHZgzuaeW9O5B">lim_const</a></td><td>If more than one plant is growing, the Heat Units for the first one will be used</td></tr><tr><td>phu_base0</td><td>Heat Units since January 1 with a base temperature of 0 deg C</td><td><a href="/pages/96M0WrCeHZgzuaeW9O5B">lim_const</a></td><td></td></tr><tr><td>precip_cur</td><td>Precipitation on the current day</td><td><a href="/pages/96M0WrCeHZgzuaeW9O5B">lim_const</a></td><td></td></tr><tr><td>precip_next</td><td>Precipitation on the next day</td><td><a href="/pages/96M0WrCeHZgzuaeW9O5B">lim_const</a></td><td></td></tr><tr><td>plant_gro</td><td>Plant growing</td><td><a href="/pages/IMuF9OtJVByGnv53JiYE">lim_var</a></td><td></td></tr><tr><td>plant_name_gro</td><td>Specific plant growing</td><td><a href="/pages/-Mb5e5Wq7qQIt3-diW5g">plant.plt</a></td><td></td></tr><tr><td>days_plant</td><td>Days since last planting</td><td><a href="/pages/96M0WrCeHZgzuaeW9O5B">lim_const</a></td><td></td></tr><tr><td>days_harv</td><td>Days since last harvest</td><td><a href="/pages/96M0WrCeHZgzuaeW9O5B">lim_const</a></td><td></td></tr><tr><td>days_irr</td><td>Days since last irrigation</td><td><a href="/pages/96M0WrCeHZgzuaeW9O5B">lim_const</a></td><td></td></tr><tr><td>days_act</td><td>Days since last action</td><td><a href="/pages/96M0WrCeHZgzuaeW9O5B">lim_const</a></td><td></td></tr><tr><td>day_start</td><td>Days since first simulation day of the year</td><td><a href="/pages/96M0WrCeHZgzuaeW9O5B">lim_const</a></td><td></td></tr><tr><td>slope</td><td>Slope of the HRU</td><td><a href="/pages/96M0WrCeHZgzuaeW9O5B">lim_const</a></td><td></td></tr><tr><td>soil_water</td><td>Total soil water in the soil profile</td><td><a href="/pages/96M0WrCeHZgzuaeW9O5B">lim_const</a>, <a href="/pages/IMuF9OtJVByGnv53JiYE">lim_var</a></td><td></td></tr><tr><td>jday</td><td>Julian day</td><td><a href="/pages/96M0WrCeHZgzuaeW9O5B">lim_const</a></td><td></td></tr><tr><td>month</td><td>Month</td><td><a href="/pages/96M0WrCeHZgzuaeW9O5B">lim_const</a></td><td></td></tr><tr><td>year_rot</td><td>Rotation year</td><td><a href="/pages/96M0WrCeHZgzuaeW9O5B">lim_const</a></td><td></td></tr><tr><td>year_gro</td><td>Growth year of perennials</td><td><a href="/pages/96M0WrCeHZgzuaeW9O5B">lim_const</a></td><td></td></tr><tr><td>year_cal</td><td>Calendar year</td><td><a href="/pages/96M0WrCeHZgzuaeW9O5B">lim_const</a></td><td></td></tr><tr><td>year_seq</td><td>Sequential year of simulation</td><td><a href="/pages/96M0WrCeHZgzuaeW9O5B">lim_const</a></td><td></td></tr><tr><td>cur_yrs<em>_</em>mat</td><td>Current years of maturity for perennial plants</td><td><a href="/pages/96M0WrCeHZgzuaeW9O5B">lim_const</a></td><td></td></tr><tr><td>biomass</td><td>Above-ground biomass</td><td></td><td></td></tr><tr><td>leaf_area</td><td>Leaf Area Index</td><td><a href="/pages/96M0WrCeHZgzuaeW9O5B">lim_const</a></td><td></td></tr><tr><td>gound_cov</td><td>Total ground cover (above-ground biomass and surface residue)</td><td></td><td></td></tr><tr><td>p_factor</td><td>USLE conservation practice factor</td><td></td><td></td></tr><tr><td>k_factor</td><td>USLE soil erodibility factor</td><td></td><td></td></tr><tr><td>hyd_soil_group</td><td>Hydrologic Soil Group</td><td></td><td></td></tr><tr><td>p_pet</td><td>Precipitation/PET ratio</td><td></td><td></td></tr><tr><td>p_lab_150</td><td>Soil labile phosphorus of first layer</td><td></td><td></td></tr><tr><td>soil_temp2</td><td>Soil temperature of second layer</td><td></td><td></td></tr><tr><td>soil_carbon</td><td>Soil organic carbon of first layer</td><td></td><td></td></tr><tr><td>tile_drained</td><td>The HRU is tile-drained</td><td></td><td></td></tr><tr><td>prob</td><td>Probability</td><td></td><td></td></tr><tr><td>prob_unif</td><td>Probability within a defined period assuming uniform distribution</td><td></td><td></td></tr><tr><td>channel_flo</td><td>Channel flow</td><td></td><td></td></tr><tr><td>tile_flo</td><td>Tile flow</td><td></td><td></td></tr><tr><td>irr_demand</td><td>Irrigation demand</td><td></td><td></td></tr><tr><td>aqu_dep</td><td>Aquifer depth below soil surface</td><td></td><td></td></tr><tr><td>land_use</td><td>Land use and management</td><td></td><td></td></tr><tr><td>tillage</td><td>Tillage system (name of tillage decision table)</td><td></td><td></td></tr><tr><td>plant_com</td><td>Plant is in the community</td><td></td><td></td></tr><tr><td>ch_order</td><td>Channel order</td><td></td><td></td></tr><tr><td>vol</td><td>Reservoir volume</td><td><a href="/pages/96M0WrCeHZgzuaeW9O5B">lim_const</a>, <a href="/pages/IMuF9OtJVByGnv53JiYE">lim_var</a></td><td></td></tr><tr><td>res_inflo</td><td>Reservoir inflow</td><td><a href="/pages/96M0WrCeHZgzuaeW9O5B">lim_const</a></td><td></td></tr><tr><td>wet_depth</td><td>Average depth of water on an impounded HRU (paddy)</td><td><a href="/pages/96M0WrCeHZgzuaeW9O5B">lim_const</a></td><td></td></tr><tr><td>weirh</td><td>Paddy weir height</td><td><a href="/pages/96M0WrCeHZgzuaeW9O5B">lim_const</a></td><td></td></tr><tr><td>vol_wet</td><td>Volume of water stored in a wetland</td><td><a href="/pages/96M0WrCeHZgzuaeW9O5B">lim_const</a>, <a href="/pages/IMuF9OtJVByGnv53JiYE">lim_var</a></td><td></td></tr></tbody></table>


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