Understanding Harvest Likelihood

The SIG report predicted HL was 21% for MBB and 11% for OH over 20 years.

Using our Best Practices equation and updated FIA data, I am calculating HL around 14.6% for MBB and 9.8% for OH.

Using our modeling equations below, I am calculating HL around 18% for MBB and 11.8% for OH.

Harvest Likelihood for MBB

Maple / beech / birch Harvest Likelihood predictors

predicting harvest over next 20 years

As we can see from the output above, the strongest predictors of harvest in MBB are:

1. Initial BAAC

a) The higher the initial BAAC the more likely there will be a harvest

2. Initial Growing Stock - though less reliable data

a) The higher the growing stock % the less likely there will be a harvest

3. Initial desirability

a) The more desirable the species the more likely there will be a harvest

4. Less influential: Initial Lorey’s Height and QMD

a) There is an inverse relationship with Lorey’s Height - taller trees result in slight decrease in harvest

b) Higher the initial QMD the more likely a harvest

Covariate Analysis for MBB

predicting harvest in next 5 years

Potential Groupings with LH for MBB

**Total represents total number of FIA plots that fall in that bin and harvested is number of FIA harvested plots in last ~5 years

Harvest Likelihood for OH

Oak / hickory Harvest Likelihood predictors

We’re seeing similar relationships as with MBB but the model has less confidence given there are fewer harvests overall. BAAC is still the strongest predictor and there is no relationship with Lorey’s Height.

Covariate Analysis for OH

Potential Groupings with LH for OH

**I suggest we don’t use bins for OH. The models are failing.