Here, you have the option to change the number of plants per hectare,
n, and your assumptions concerning many other things of importance. You
instantly get the present value per hectare.
The variables and parameters are:
F = Fix cost per hectare at the time of the investment (site preparation
etc.).
c = Cost per plant (the price per plant when you buy them + the
cost of the plantation activity).
n = The number of plants per hectare.
x = The probability that a plant survives.
r = The rate of interest in continuous time.
t = The number of years until it the harvest takes place.
p = Net price per cubic metre when it is time to harvest.
v = The average volume production per hectare and year during the
life of the trees in the
age interval [0 - t] in case the
number of surviving stems is 2000 per hectare.
L = Land value per hectare after the harvest.
U = Relative production ( = The real production divided by the production
which would take place
with 2000 surviving stems per
hectare).
VOL = The harvest volume, cubic metres, per hectare.
nsurv = The number of surviving stems per hectare.
MVOL = The average volume per stem when it is time to harvest.
Present Value = - F - c*n + EXP(-rt)(p*VOL
+ L)
Good Luck!
Peter Lohmnader
Background and References:
See this link and the included references: http://www.sekon.SLU.se/~plo/svepl5.html