Kelsey,

There should be no problem simulating legumes - the N-fixation routine
will work with forages as well as grains.  The main issue is that nobody
has developed alfalfa or temperate grass species files for DSSAT.  If
you want to run a mix of species (ex. timothy planted with alfalfa), you
will need to develop a species file that characterizes the mix rather
than individual species as DSSAT can simulate only a single species at a
time.  We cannot simulate competition between crops in DSSAT at this
time.  Maybe someone is working on these issues?

Are you looking to run single-season simulations or multiple,
consecutive years?  There are issues with perennial crops in the
distribution version of DSSAT.  These issues relate to winter dormancy
and freeze damage.  We have been working on a forage version of DSSAT at
the University of Florida but I'm not sure where we stand on
development.  We added daylength-sensitive functions to alter
partitioning and mobilization patterns and also modified the
freeze-damage routine (among other things) to allow a partial kill and
persistence after a freeze.  Ken Boote has hired Gopal Kakani to
continue development of that version but he will be working primarily on
developing a bermudagrass species file.

Stu

Stuart Rymph
Land O'Lakes Purina Feed LLC
with obligations to University of Florida Agronomy Dept.
6063 Beckman Rd.
Mazomanie, WI 53560
[log in to unmask]

Brandt, Kelsey wrote:
> Hi all,
>
>
>
> We are planning to simulate grassland/forage/pasture using DSSAT.  However, we have identified Bahai and Brachiaria grasses as the only forages in DSSAT.  Because of the nature of pastures and grasslands we need to simulate these with more than just grasses.  They need to include legumes (clover and alfalfa), and grasses as well as small shrubs and forbs.  We also need to simulate alfalfa as a single crop.  Are there any models within the DSSAT group that simulate these situations?  Also, is there anyone developing such a simulation within DSSAT?  Any help on this would be much appreciated.
>
>
>
> Regards,
>
>
>
> Kelsey Brandt
> Agriculture and Agri-Food Canada/Agriculture et Agroalimentaire Canada
> Telephone/Téléphone: 306-778-3107
> Facsimile/Télécopieur: 306-788-3188
>
> P.O. Box 1030, # 1 Airport Road
>
> Swift Current, Saskatchewan, Canada
> S9H 3X2
>
> [log in to unmask] <mailto:[log in to unmask]>
>
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>
>