Vol. 51—1997 - NorthEastern Weed Science Society

December 24, 1994
138
sets the
peculiar
.Two envir
to produc
(Hereafte
'fertiliz
of land d
corner, t
of fertil
expands t
fertilize
the weedy
the 5 ton
more, low
of weeds,
land and
antity, I reckon environmental expense for a
tons.
nmental expenses, hectares and nitrogen fertilizer,
the 5 tons form the coordinates of Fig 7.
I abbreviate 'nitrogen fertilizer' as
r'.) The expense of fertilizer falls downward and
creases leftward on the graph. In the upper right
e datum for IRS rice lies out of sight; a high rate
zer grows luxurious weeds, depresses rice yield and
e area to grow 5 tons, multiplying the kilograms of
used. Applying less fertilizer raises the yield of
rice, but still, over 6 hectares are used to grow
. Among the weeds, variety C4-63 yields somewhat
ring the expense of both land and fertilizer. Free
variety matters little, and the expenses of both
ertilizer are small.