NOTE: You might find it
worthwhile to read the comments
that go with recent upgrades to find out what
capabilities have been added recently. However, you only need to
download the most recent upgrade to be brought up to date. Also,
go here to see if you have the most recent Java Runtime Environment.
1) Click below next to the latest
upgrade and allow your browser
to unzip the file inside of the same directory that contains the
Habgen1 directory. Don't unzip it inside of
the Habgen1 directory. Allow the unzip process to write over any
pre-existing files. This will only change files inside of the old
You can back out of an upgrade by
installing an older upgrade.
The newest upgrade accumulates all earlier upgrades. If you
can't unzip the file, it may have been corrupted during the
download. Try downloading again, and if that doesn't work ask for
the file to be emailed .
-January 30, 2005 Upgrade
Another minor bug fix. Putting a "-" within a regime name was
causing problems. This was due to some legacy code that gave
dashes special treatment. Now its OK to embed a dash in the
regime class name. After installing this upgrade, Habgen should
have January 30, 2006 in the main window title.
-January 05, 2005 Upgrade
There was a bug in the thinning response function for the PMRC models
that has been fixed.
Make sure your copy of Habgen says January 5b, 2006 in the title of the
There was a last minute change inserted that superceded the original
January 5 release.
-November 28, 2005 Upgrade
A new feature has been added to the Biological Output Tab. You
can get the NPV or LEV calculations to only use the last output
year. This is useful for "Habitat" style flows where each year
has a cumulative output value. Therefore, the last year gives the
amount that is available at the end of the planning horizon. In
this case, you may want NPV calculations to only use the last year
value. See the "Biological Output Table" manual section for more
-November 15, 2005 Upgrade
a) Now when Habgen starts up you are immediately asked if you want to
open a 1) Previous, 2) Other, or 3)
run. Previous is what
Habgen used to do automatically. Other would be some other saved
Habgen run (not necessarily previous), and new allows you to start a
completely new run. Prior to this upgrade it was somewhat
difficult to get Habgen to let you get away from previously saved
b) It is now possible to compute LEV as well as NPV for the Bio Output
Table. There are significant changes to how the Bio Output Table
computed You can now initialize the Bio Output Table and then
specific rows when
computing NPV or LEV. This allows you to change the value or cost
for different regimes. For example, land sale regimes might have
See the "Biological Output Table" manual section for more
-October 13, 2005 Upgrade
There are many new features and changes in this upgrade. You should
download the new manual and look through it:
1) The regime naming scheme was changed a little. You should look
the Regime Class section in the manual for details.
2) There are herbicide and bedding options when planting for the PMRC
3) There is a new Fertilizer option (Nitrogen and phophorus) for
the PMRC models
4) The pmrc product breakdown equation is now incorporated. Push
button on the model setup form to use it. This causes the yields
to be adjusted according
to the diameter limits you input. Typically, this lets you split
the yield into pulpwood, chip-n-saw and sawtimber.
5) There are now 3 flow output tables. You can select the flow table
that will receive
the output from the model runs. This will let you create 3
different flows and operate on them
with the tools described below. For example, you could have
pulpwood, chip-n-saw and sawtimber
6) The bio-weights table is gone and an "NPV" button is added to
the Bio-Output table. Push this button and you can supply a value
for each of the 3 flows and an interest rate. Then push the
"Merge Flows" button
and the value column in the Bio-Output table is computed as
sum[value*flow/(1+i)^n]. This assumes that the
3 flow tables are compatible, i.e. they contain the same regimes and
output years. If a table is not compatible, it
is skipped. If you set interest rate to 0.0 and
values to 1.0, this would just sum all the flow outputs.
There is also a "Cost" button that lets you include per acre costs that
will occur at each regime action year.
7) Each flow table now has some additional spreadsheet like
capability. Currently, this
gives the ability to do 3 things:
a) Apply a decay function to the flow. If the flow
represents carbon outputs, the decay function computes the
cumulative remaining carbon for the rest of the planning horizon (you
specify the half life=h). The decay function is
(1/(1+log(2)/h))^n, where n is the number of years since the
harvest. This is useful for developing carbon
schedules where you want to keep track of carbon in products, e.g.
pulpwood or sawtimber.
b) Add flowB to the current flow, where flowB can be
weighted. You can also add flow to itself multiplied by a
weight. Suppose the weight is 0.2, then you make it 20%
bigger. Also, if flow is decayed product and flowB is residual
carbon, then adding them results in total carbon on the
land and in products.
c) Copy another flow table to this flow table. Might be
useful if you want to retain the original table and then make some
Finally, since this upgrade represents a major reconfiguration of
Habgen, your old settings in hbg/HabgenSettings.hbg should be deleted
if you did an upgrade.
In other words, you'll need to start from scratch if you do an upgrade,
so it might make sense to just go ahead and delete your old
installation of Habgen and
reinstall the full version to avoid problems.