alfalfa, hay
plantpop
400.0
dmaxshoot
1.0
cbaflag
0
tgtyield
3.0
cbafact
1.0
cyrafact
1.0
hyldflag
2
hyldunits
ton/ac
hyldwater
15.0
hyconfact
4.465
idc
3
grf
1.0
ck
0.69
hui0
0.9
hmx
1.0
growdepth
0.01
rdmx
2.0
tbas
3.0
topt
30.0
thudf
1
dtm
120
thum
1800.0
frsx1
-5.0
frsx2
-9.44444
frsy1
0.01
frsy2
0.95
verndel
0.0
bceff
30
a_lf
0.023
b_lf
0.8063
c_lf
0.4146
d_lf
-0.061
a_rp
-0.024
b_rp
0.9911
c_rp
0.6435
d_rp
0.0494
a_ht
0.2
b_ht
-0.075
ssaa
3.9
ssab
1.0
sla
30
huie
0.05
transf
0
diammax
0.3
storeinit
2.0
mshoot
110.0
leafstem
0.6
fshoot
0.013
leaf2stor
0.2
stem2stor
0.2
stor2stor
0.1
rbc
2
standdk
0.0536
surfdk
0.0536
burieddk
0.0536
rootdk
0.0536
stemnodk
0.2
stemdia
0.0020
thrddys
20.0
covfact
7.0
resevapa
-1.20379
resevapb
0.604887
yield_coefficient
0.0
residue_intercept
0.0
regrow_location
0.0
noparam3
0.0
noparam2
0.0
noparam1
0.0
crop_notes
Size ranges
J.J. rquez-Ortiz, J.F.S. Lamb, L.D. Johnson, D.K. Barnes and R.E. Stucker, 1999, Heritability of crown traits in alfalfa, Crop Science, Vol 39, Issue 1 pgs. 38-43
Crown Depth (distance from the soil level to the top of the tap root) - 0.5cm to 5cm
Crown width (just below the soil surface) - 2cm to 12cm or greater
Number of crown stems - 2 to 10 or more
Crown stem width - 2mm to 6mm or greater
Number of crown buds - none to 12 or more
D.K. Barnes, R.B. Pearce, G.E. Carlson, R.H. Hart, and C.H. Hanson. 1969. SPecific Leaf Weight Differences in Alfalfa Associated with Variety and
Plant Age. Crop Science, Vol 9, pgs. 421-423.
Values of Specific leaf weight measured in the paper varied from 2.15 to 4.3, with early season growth mostly in the area of 2.15 to 2.72 mg/cm^2
Conversion to m^2/kg is * 10^6 mg/kg * 10^-4 m^2/cm^2 = 100 / mg/cm^2
2.15 mg/cm^2 = 100 / 2.15 m^2/kg = 46.5 m^2/kg, 100 / 2.72 = 36.8, 100 / 4.3 = 23.3
M. H. Hall, C. J. Nelson, J. H. Coutts and R. C. Stout. 2004. Effect of Seeding Rate on Alfalfa Stand Longevity. Agron. J. 96:717-722
Stem densities for the MO94 study (data not presented) were not different among seeding rates at any sampling time. There were 623 stems m–2 13 MAP
and only 350 stems m–2 by 25 MAP. Stem density remained nearly constant at that level through 49 MAP. During the same time period, plant density
declined from an average of 100 down to 25 plants m–2. This means that there was a fourfold increase in stems per plant from 25 to 49 MAP during
the same time period. Thereafter, stem density continued to decline to 290 and 260 stems m–2 at 63 and 73 MAP, respectively, while plant density fell
below 15 plants m–2 during the same time period. Crowns develop stems in response to light (Cowett and Sprague, 1962) and apparently could not
continue to maintain high stem density with the thin stand and older plants.
data as shown above.
MAP = months after planting
SPM2 = stems per square meter
PPM2 = plants per square meter
SPP = stems per plant
MAP SPM2 PPM2 SPP
13 623 100 62.3
25 350 36 9.7
49 350 25 14
63 290 16 18
73 260 13 20
With the critical period of alfalfa being establishment, a stem count, equals plant count of 400 stems per square meter is used to try and get early cover.
Fick, G.W., D.A. Holt, D.G. Lugg. 1988. Environmental Physiology and Crop Growth. in A.A. Hanson, D.K. Barnes, R.R. Hill , Jr., eds. 1988 Alfalfa and Alfalfa
Improvement. Agronomy Monograph Number 29. American Society of Agronomy.
page 181. Growth temperatures: GDD base from 0 to 5 C, varies depending on time of year. GDD totals 0 C base, 700 to bud, 880 to first flower,
1075 to full bloom, 1900 to ripe seed stages. Suggests a GDD max temperature around 30 C