Recent upgrades for Habgen can be downloaded from this location.   The upgrades only include enough class files to upgrade an existing COMPLETE Habgen installation.  To determine if you need to upgrade, run your current version of Habgen and check the version date  in the title bar.  If it's older than the most recent upgrade posted here, then you need to upgrade.

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 Habgen1 directory.

-January 30, 2005  Upgrade ==>:  Click Here
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 ==>:  Click Here
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 main window.
There was a last minute change inserted that superceded the original January 5 release.

-November 28, 2005  Upgrade ==>:  Click Here
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 information

- -November 15, 2005  Upgrade ==>:  Click Here

a) Now when Habgen starts up you are immediately asked if you want to open a 1) Previous, 2) Other, or 3) New  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 settings.
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 is computed  You can now initialize the Bio Output Table and then select specific rows when computing NPV or LEV.  This allows you to change the value or cost settings for different regimes.  For example, land sale regimes might have a negative cost.   See the "Biological Output Table"  manual section for more information

- -October 13, 2005  Upgrade ==>:  Click Here

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 at the Regime Class section in the manual for details.
2) There are herbicide and bedding options when planting for the PMRC growth models
3)  There is a new Fertilizer option (Nitrogen and phophorus) for the PMRC models
4) The pmrc product breakdown equation is now incorporated.  Push the "Product"  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  flows.
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 changes.

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.